#
#
# The Nim Compiler
# (c) Copyright 2015 Andreas Rumpf
#
# See the file "copying.txt", included in this
# distribution, for details about the copyright.
#
## This file implements the new evaluation engine for Nim code.
## An instruction is 1-3 int32s in memory, it is a register based VM.
import
std/[strutils, tables, parseutils],
msgs, vmdef, vmgen, nimsets, types, passes,
parser, vmdeps, idents, trees, renderer, options, transf,
vmmarshal, gorgeimpl, lineinfos, btrees, macrocacheimpl,
modulegraphs, sighashes, int128, vmprofiler
import ast except getstr
from semfold import leValueConv, ordinalValToString
from evaltempl import evalTemplate
from magicsys import getSysType
const
traceCode = defined(nimVMDebug)
when hasFFI:
import evalffi
proc stackTraceAux(c: PCtx; x: PStackFrame; pc: int; recursionLimit=100) =
if x != nil:
if recursionLimit == 0:
var calls = 0
var x = x
while x != nil:
inc calls
x = x.next
msgWriteln(c.config, $calls & " calls omitted\n", {msgNoUnitSep})
return
stackTraceAux(c, x.next, x.comesFrom, recursionLimit-1)
var info = c.debug[pc]
# we now use a format similar to the one in lib/system/excpt.nim
var s = ""
# todo: factor with quotedFilename
if optExcessiveStackTrace in c.config.globalOptions:
s = toFullPath(c.config, info)
else:
s = toFilename(c.config, info)
var line = toLinenumber(info)
var col = toColumn(info)
if line > 0:
s.add('(')
s.add($line)
s.add(", ")
s.add($(col + ColOffset))
s.add(')')
if x.prc != nil:
for k in 1..max(1, 25-s.len): s.add(' ')
s.add(x.prc.name.s)
msgWriteln(c.config, s, {msgNoUnitSep})
proc stackTraceImpl(c: PCtx, tos: PStackFrame, pc: int,
msg: string, lineInfo: TLineInfo, infoOrigin: InstantiationInfo) {.noinline.} =
# noinline to avoid code bloat
msgWriteln(c.config, "stack trace: (most recent call last)", {msgNoUnitSep})
stackTraceAux(c, tos, pc)
let action = if c.mode == emRepl: doRaise else: doNothing
# XXX test if we want 'globalError' for every mode
let lineInfo = if lineInfo == TLineInfo.default: c.debug[pc] else: lineInfo
liMessage(c.config, lineInfo, errGenerated, msg, action, infoOrigin)
template stackTrace(c: PCtx, tos: PStackFrame, pc: int,
msg: string, lineInfo: TLineInfo = TLineInfo.default) =
stackTraceImpl(c, tos, pc, msg, lineInfo, instantiationInfo(-2, fullPaths = true))
return
proc bailOut(c: PCtx; tos: PStackFrame) =
stackTrace(c, tos, c.exceptionInstr, "unhandled exception: " &
c.currentExceptionA[3].skipColon.strVal &
" [" & c.currentExceptionA[2].skipColon.strVal & "]")
when not defined(nimComputedGoto):
{.pragma: computedGoto.}
proc ensureKind(n: var TFullReg, kind: TRegisterKind) =
if n.kind != kind:
n = TFullReg(kind: kind)
template ensureKind(k: untyped) {.dirty.} =
ensureKind(regs[ra], k)
template decodeB(k: untyped) {.dirty.} =
let rb = instr.regB
ensureKind(k)
template decodeBC(k: untyped) {.dirty.} =
let rb = instr.regB
let rc = instr.regC
ensureKind(k)
template declBC() {.dirty.} =
let rb = instr.regB
let rc = instr.regC
template decodeBImm(k: untyped) {.dirty.} =
let rb = instr.regB
let imm = instr.regC - byteExcess
ensureKind(k)
template decodeBx(k: untyped) {.dirty.} =
let rbx = instr.regBx - wordExcess
ensureKind(k)
template move(a, b: untyped) {.dirty.} = system.shallowCopy(a, b)
# XXX fix minor 'shallowCopy' overloading bug in compiler
proc derefPtrToReg(address: BiggestInt, typ: PType, r: var TFullReg, isAssign: bool): bool =
# nim bug: `isAssign: static bool` doesn't work, giving odd compiler error
template fun(field, T, rkind) =
if isAssign:
cast[ptr T](address)[] = T(r.field)
else:
r.ensureKind(rkind)
let val = cast[ptr T](address)[]
when T is SomeInteger | char:
r.field = BiggestInt(val)
else:
r.field = val
return true
## see also typeinfo.getBiggestInt
case typ.kind
of tyChar: fun(intVal, char, rkInt)
of tyInt: fun(intVal, int, rkInt)
of tyInt8: fun(intVal, int8, rkInt)
of tyInt16: fun(intVal, int16, rkInt)
of tyInt32: fun(intVal, int32, rkInt)
of tyInt64: fun(intVal, int64, rkInt)
of tyUInt: fun(intVal, uint, rkInt)
of tyUInt8: fun(intVal, uint8, rkInt)
of tyUInt16: fun(intVal, uint16, rkInt)
of tyUInt32: fun(intVal, uint32, rkInt)
of tyUInt64: fun(intVal, uint64, rkInt) # note: differs from typeinfo.getBiggestInt
of tyFloat: fun(floatVal, float, rkFloat)
of tyFloat32: fun(floatVal, float32, rkFloat)
of tyFloat64: fun(floatVal, float64, rkFloat)
else: return false
proc createStrKeepNode(x: var TFullReg; keepNode=true) =
if x.node.isNil or not keepNode:
x.node = newNode(nkStrLit)
elif x.node.kind == nkNilLit and keepNode:
when defined(useNodeIds):
let id = x.node.id
x.node[] = TNode(kind: nkStrLit)
when defined(useNodeIds):
x.node.id = id
elif x.node.kind notin {nkStrLit..nkTripleStrLit} or
nfAllConst in x.node.flags:
# XXX this is hacky; tests/txmlgen triggers it:
x.node = newNode(nkStrLit)
# It not only hackey, it is also wrong for tgentemplate. The primary
# cause of bugs like these is that the VM does not properly distinguish
# between variable definitions (var foo = e) and variable updates (foo = e).
include vmhooks
template createStr(x) =
x.node = newNode(nkStrLit)
template createSet(x) =
x.node = newNode(nkCurly)
proc moveConst(x: var TFullReg, y: TFullReg) =
x.ensureKind(y.kind)
case x.kind
of rkNone: discard
of rkInt: x.intVal = y.intVal
of rkFloat: x.floatVal = y.floatVal
of rkNode: x.node = y.node
of rkRegisterAddr: x.regAddr = y.regAddr
of rkNodeAddr: x.nodeAddr = y.nodeAddr
# this seems to be the best way to model the reference semantics
# of system.NimNode:
template asgnRef(x, y: untyped) = moveConst(x, y)
proc copyValue(src: PNode): PNode =
if src == nil or nfIsRef in src.flags:
return src
result = newNode(src.kind)
result.info = src.info
result.typ = src.typ
result.flags = src.flags * PersistentNodeFlags
result.comment = src.comment
when defined(useNodeIds):
if result.id == nodeIdToDebug:
echo "COMES FROM ", src.id
case src.kind
of nkCharLit..nkUInt64Lit: result.intVal = src.intVal
of nkFloatLit..nkFloat128Lit: result.floatVal = src.floatVal
of nkSym: result.sym = src.sym
of nkIdent: result.ident = src.ident
of nkStrLit..nkTripleStrLit: result.strVal = src.strVal
else:
newSeq(result.sons, src.len)
for i in 0..<src.len:
result[i] = copyValue(src[i])
proc asgnComplex(x: var TFullReg, y: TFullReg) =
x.ensureKind(y.kind)
case x.kind
of rkNone: discard
of rkInt: x.intVal = y.intVal
of rkFloat: x.floatVal = y.floatVal
of rkNode: x.node = copyValue(y.node)
of rkRegisterAddr: x.regAddr = y.regAddr
of rkNodeAddr: x.nodeAddr = y.nodeAddr
proc fastAsgnComplex(x: var TFullReg, y: TFullReg) =
x.ensureKind(y.kind)
case x.kind
of rkNone: discard
of rkInt: x.intVal = y.intVal
of rkFloat: x.floatVal = y.floatVal
of rkNode: x.node = y.node
of rkRegisterAddr: x.regAddr = y.regAddr
of rkNodeAddr: x.nodeAddr = y.nodeAddr
proc writeField(n: var PNode, x: TFullReg) =
case x.kind
of rkNone: discard
of rkInt:
if n.kind == nkNilLit:
n[] = TNode(kind: nkIntLit) # ideally, `nkPtrLit`
n.intVal = x.intVal
of rkFloat: n.floatVal = x.floatVal
of rkNode: n = copyValue(x.node)
of rkRegisterAddr: writeField(n, x.regAddr[])
of rkNodeAddr: n = x.nodeAddr[]
proc putIntoReg(dest: var TFullReg; n: PNode) =
case n.kind
of nkStrLit..nkTripleStrLit:
dest = TFullReg(kind: rkNode, node: newStrNode(nkStrLit, n.strVal))
of nkIntLit: # use `nkPtrLit` once this is added
if dest.kind == rkNode: dest.node = n
elif n.typ != nil and n.typ.kind in PtrLikeKinds:
dest = TFullReg(kind: rkNode, node: n)
else:
dest = TFullReg(kind: rkInt, intVal: n.intVal)
of {nkCharLit..nkUInt64Lit} - {nkIntLit}:
dest = TFullReg(kind: rkInt, intVal: n.intVal)
of nkFloatLit..nkFloat128Lit:
dest = TFullReg(kind: rkFloat, floatVal: n.floatVal)
else:
dest = TFullReg(kind: rkNode, node: n)
proc regToNode(x: TFullReg): PNode =
case x.kind
of rkNone: result = newNode(nkEmpty)
of rkInt: result = newNode(nkIntLit); result.intVal = x.intVal
of rkFloat: result = newNode(nkFloatLit); result.floatVal = x.floatVal
of rkNode: result = x.node
of rkRegisterAddr: result = regToNode(x.regAddr[])
of rkNodeAddr: result = x.nodeAddr[]
template getstr(a: untyped): untyped =
(if a.kind == rkNode: a.node.strVal else: $chr(int(a.intVal)))
proc pushSafePoint(f: PStackFrame; pc: int) =
f.safePoints.add(pc)
proc popSafePoint(f: PStackFrame) =
discard f.safePoints.pop()
type
ExceptionGoto = enum
ExceptionGotoHandler,
ExceptionGotoFinally,
ExceptionGotoUnhandled
proc findExceptionHandler(c: PCtx, f: PStackFrame, exc: PNode):
tuple[why: ExceptionGoto, where: int] =
let raisedType = exc.typ.skipTypes(abstractPtrs)
while f.safePoints.len > 0:
var pc = f.safePoints.pop()
var matched = false
var pcEndExcept = pc
# Scan the chain of exceptions starting at pc.
# The structure is the following:
# pc - opcExcept, <end of this block>
# - opcExcept, <pattern1>
# - opcExcept, <pattern2>
# ...
# - opcExcept, <patternN>
# - Exception handler body
# - ... more opcExcept blocks may follow
# - ... an optional opcFinally block may follow
#
# Note that the exception handler body already contains a jump to the
# finally block or, if that's not present, to the point where the execution
# should continue.
# Also note that opcFinally blocks are the last in the chain.
while c.code[pc].opcode == opcExcept:
# Where this Except block ends
pcEndExcept = pc + c.code[pc].regBx - wordExcess
inc pc
# A series of opcExcept follows for each exception type matched
while c.code[pc].opcode == opcExcept:
let excIndex = c.code[pc].regBx - wordExcess
let exceptType =
if excIndex > 0: c.types[excIndex].skipTypes(abstractPtrs)
else: nil
# echo typeToString(exceptType), " ", typeToString(raisedType)
# Determine if the exception type matches the pattern
if exceptType.isNil or inheritanceDiff(raisedType, exceptType) <= 0:
matched = true
break
inc pc
# Skip any further ``except`` pattern and find the first instruction of
# the handler body
while c.code[pc].opcode == opcExcept:
inc pc
if matched:
break
# If no handler in this chain is able to catch this exception we check if
# the "parent" chains are able to. If this chain ends with a `finally`
# block we must execute it before continuing.
pc = pcEndExcept
# Where the handler body starts
let pcBody = pc
if matched:
return (ExceptionGotoHandler, pcBody)
elif c.code[pc].opcode == opcFinally:
# The +1 here is here because we don't want to execute it since we've
# already pop'd this statepoint from the stack.
return (ExceptionGotoFinally, pc + 1)
return (ExceptionGotoUnhandled, 0)
proc cleanUpOnReturn(c: PCtx; f: PStackFrame): int =
# Walk up the chain of safepoints and return the PC of the first `finally`
# block we find or -1 if no such block is found.
# Note that the safepoint is removed once the function returns!
result = -1
# Traverse the stack starting from the end in order to execute the blocks in
# the intended order
for i in 1..f.safePoints.len:
var pc = f.safePoints[^i]
# Skip the `except` blocks
while c.code[pc].opcode == opcExcept:
pc += c.code[pc].regBx - wordExcess
if c.code[pc].opcode == opcFinally:
discard f.safePoints.pop
return pc + 1
proc opConv(c: PCtx; dest: var TFullReg, src: TFullReg, desttyp, srctyp: PType): bool =
if desttyp.kind == tyString:
dest.ensureKind(rkNode)
dest.node = newNode(nkStrLit)
let styp = srctyp.skipTypes(abstractRange)
case styp.kind
of tyEnum:
let n = styp.n
let x = src.intVal.int
if x <% n.len and (let f = n[x].sym; f.position == x):
dest.node.strVal = if f.ast.isNil: f.name.s else: f.ast.strVal
else:
for i in 0..<n.len:
if n[i].kind != nkSym: internalError(c.config, "opConv for enum")
let f = n[i].sym
if f.position == x:
dest.node.strVal = if f.ast.isNil: f.name.s else: f.ast.strVal
return
dest.node.strVal = styp.sym.name.s & " " & $x
of tyInt..tyInt64:
dest.node.strVal = $src.intVal
of tyUInt..tyUInt64:
dest.node.strVal = $uint64(src.intVal)
of tyBool:
dest.node.strVal = if src.intVal == 0: "false" else: "true"
of tyFloat..tyFloat128:
dest.node.strVal = $src.floatVal
of tyString:
dest.node.strVal = src.node.strVal
of tyCstring:
if src.node.kind == nkBracket:
# Array of chars
var strVal = ""
for son in src.node.sons:
let c = char(son.intVal)
if c == '\0': break
strVal.add(c)
dest.node.strVal = strVal
else:
dest.node.strVal = src.node.strVal
of tyChar:
dest.node.strVal = $chr(src.intVal)
else:
internalError(c.config, "cannot convert to string " & desttyp.typeToString)
else:
let desttyp = skipTypes(desttyp, abstractVarRange)
case desttyp.kind
of tyInt..tyInt64:
dest.ensureKind(rkInt)
case skipTypes(srctyp, abstractRange).kind
of tyFloat..tyFloat64:
dest.intVal = int(src.floatVal)
else:
dest.intVal = src.intVal
if toInt128(dest.intVal) < firstOrd(c.config, desttyp) or toInt128(dest.intVal) > lastOrd(c.config, desttyp):
return true
of tyUInt..tyUInt64:
dest.ensureKind(rkInt)
let styp = srctyp.skipTypes(abstractRange) # skip distinct types(dest type could do this too if needed)
case styp.kind
of tyFloat..tyFloat64:
dest.intVal = int(src.floatVal)
else:
let srcDist = (sizeof(src.intVal) - styp.size) * 8
let destDist = (sizeof(dest.intVal) - desttyp.size) * 8
var value = cast[BiggestUInt](src.intVal)
value = (value shl srcDist) shr srcDist
value = (value shl destDist) shr destDist
dest.intVal = cast[BiggestInt](value)
of tyBool:
dest.ensureKind(rkInt)
dest.intVal =
case skipTypes(srctyp, abstractRange).kind
of tyFloat..tyFloat64: int(src.floatVal != 0.0)
else: int(src.intVal != 0)
of tyFloat..tyFloat64:
dest.ensureKind(rkFloat)
case skipTypes(srctyp, abstractRange).kind
of tyInt..tyInt64, tyUInt..tyUInt64, tyEnum, tyBool, tyChar:
dest.floatVal = toBiggestFloat(src.intVal)
else:
dest.floatVal = src.floatVal
of tyObject:
if srctyp.skipTypes(abstractVarRange).kind != tyObject:
internalError(c.config, "invalid object-to-object conversion")
# A object-to-object conversion is essentially a no-op
moveConst(dest, src)
else:
asgnComplex(dest, src)
proc compile(c: PCtx, s: PSym): int =
result = vmgen.genProc(c, s)
when debugEchoCode: c.echoCode result
#c.echoCode
template handleJmpBack() {.dirty.} =
if c.loopIterations <= 0:
if allowInfiniteLoops in c.features:
c.loopIterations = c.config.maxLoopIterationsVM
else:
msgWriteln(c.config, "stack trace: (most recent call last)", {msgNoUnitSep})
stackTraceAux(c, tos, pc)
globalError(c.config, c.debug[pc], errTooManyIterations % $c.config.maxLoopIterationsVM)
dec(c.loopIterations)
proc recSetFlagIsRef(arg: PNode) =
if arg.kind notin {nkStrLit..nkTripleStrLit}:
arg.flags.incl(nfIsRef)
for i in 0..<arg.safeLen:
arg[i].recSetFlagIsRef
proc setLenSeq(c: PCtx; node: PNode; newLen: int; info: TLineInfo) =
let typ = node.typ.skipTypes(abstractInst+{tyRange}-{tyTypeDesc})
let oldLen = node.len
setLen(node.sons, newLen)
if oldLen < newLen:
for i in oldLen..<newLen:
node[i] = getNullValue(typ[0], info, c.config)
const
errNilAccess = "attempt to access a nil address"
errOverOrUnderflow = "over- or underflow"
errConstantDivisionByZero = "division by zero"
errIllegalConvFromXtoY = "illegal conversion from '$1' to '$2'"
errTooManyIterations = "interpretation requires too many iterations; " &
"if you are sure this is not a bug in your code, compile with `--maxLoopIterationsVM:number` (current value: $1)"
errFieldXNotFound = "node lacks field: "
template maybeHandlePtr(node2: PNode, reg: TFullReg, isAssign2: bool): bool =
let node = node2 # prevent double evaluation
if node.kind == nkNilLit:
stackTrace(c, tos, pc, errNilAccess)
let typ = node.typ
if nfIsPtr in node.flags or (typ != nil and typ.kind == tyPtr):
assert node.kind == nkIntLit, $(node.kind)
assert typ != nil
let typ2 = if typ.kind == tyPtr: typ[0] else: typ
if not derefPtrToReg(node.intVal, typ2, reg, isAssign = isAssign2):
# tyObject not supported in this context
stackTrace(c, tos, pc, "deref unsupported ptr type: " & $(typeToString(typ), typ.kind))
true
else:
false
when not defined(nimHasSinkInference):
{.pragma: nosinks.}
proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
var pc = start
var tos = tos
# Used to keep track of where the execution is resumed.
var savedPC = -1
var savedFrame: PStackFrame
when defined(gcArc) or defined(gcOrc):
template updateRegsAlias = discard
template regs: untyped = tos.slots
else:
template updateRegsAlias =
move(regs, tos.slots)
var regs: seq[TFullReg] # alias to tos.slots for performance
updateRegsAlias
#echo "NEW RUN ------------------------"
while true:
#{.computedGoto.}
let instr = c.code[pc]
let ra = instr.regA
when traceCode:
template regDescr(name, r): string =
let kind = if r < regs.len: $regs[r].kind else: ""
let ret = name & ": " & $r & " " & $kind
alignLeft(ret, 15)
echo "PC:$pc $opcode $ra $rb $rc" % [
"pc", $pc, "opcode", alignLeft($c.code[pc].opcode, 15),
"ra", regDescr("ra", ra), "rb", regDescr("rb", instr.regB),
"rc", regDescr("rc", instr.regC)]
if c.config.isVmTrace:
# unlike nimVMDebug, this doesn't require re-compiling nim and is controlled by user code
let info = c.debug[pc]
# other useful variables: c.loopIterations
echo "$# [$#] $#" % [c.config$info, $instr.opcode, c.config.sourceLine(info)]
c.profiler.enter(c, tos)
case instr.opcode
of opcEof: return regs[ra]
of opcRet:
let newPc = c.cleanUpOnReturn(tos)
# Perform any cleanup action before returning
if newPc < 0:
pc = tos.comesFrom
let retVal = regs[0]
tos = tos.next
if tos.isNil:
return retVal
updateRegsAlias
assert c.code[pc].opcode in {opcIndCall, opcIndCallAsgn}
if c.code[pc].opcode == opcIndCallAsgn:
regs[c.code[pc].regA] = retVal
else:
savedPC = pc
savedFrame = tos
# The -1 is needed because at the end of the loop we increment `pc`
pc = newPc - 1
of opcYldYoid: assert false
of opcYldVal: assert false
of opcAsgnInt:
decodeB(rkInt)
regs[ra].intVal = regs[rb].intVal
of opcAsgnFloat:
decodeB(rkFloat)
regs[ra].floatVal = regs[rb].floatVal
of opcCastFloatToInt32:
let rb = instr.regB
ensureKind(rkInt)
regs[ra].intVal = cast[int32](float32(regs[rb].floatVal))
of opcCastFloatToInt64:
let rb = instr.regB
ensureKind(rkInt)
regs[ra].intVal = cast[int64](regs[rb].floatVal)
of opcCastIntToFloat32:
let rb = instr.regB
ensureKind(rkFloat)
regs[ra].floatVal = cast[float32](regs[rb].intVal)
of opcCastIntToFloat64:
let rb = instr.regB
ensureKind(rkFloat)
regs[ra].floatVal = cast[float64](regs[rb].intVal)
of opcCastPtrToInt: # RENAME opcCastPtrOrRefToInt
decodeBImm(rkInt)
case imm
of 1: # PtrLikeKinds
case regs[rb].kind
of rkNode:
regs[ra].intVal = cast[int](regs[rb].node.intVal)
of rkNodeAddr:
regs[ra].intVal = cast[int](regs[rb].nodeAddr)
else:
stackTrace(c, tos, pc, "opcCastPtrToInt: got " & $regs[rb].kind)
of 2: # tyRef
regs[ra].intVal = cast[int](regs[rb].node)
else: assert false, $imm
of opcCastIntToPtr:
let rb = instr.regB
let typ = regs[ra].node.typ
let node2 = newNodeIT(nkIntLit, c.debug[pc], typ)
case regs[rb].kind
of rkInt: node2.intVal = regs[rb].intVal
of rkNode:
if regs[rb].node.typ.kind notin PtrLikeKinds:
stackTrace(c, tos, pc, "opcCastIntToPtr: regs[rb].node.typ: " & $regs[rb].node.typ.kind)
node2.intVal = regs[rb].node.intVal
else: stackTrace(c, tos, pc, "opcCastIntToPtr: regs[rb].kind: " & $regs[rb].kind)
regs[ra].node = node2
of opcAsgnComplex:
asgnComplex(regs[ra], regs[instr.regB])
of opcFastAsgnComplex:
fastAsgnComplex(regs[ra], regs[instr.regB])
of opcAsgnRef:
asgnRef(regs[ra], regs[instr.regB])
of opcNodeToReg:
let ra = instr.regA
let rb = instr.regB
# opcDeref might already have loaded it into a register. XXX Let's hope
# this is still correct this way:
if regs[rb].kind != rkNode:
regs[ra] = regs[rb]
else:
assert regs[rb].kind == rkNode
let nb = regs[rb].node
case nb.kind
of nkCharLit..nkUInt64Lit:
ensureKind(rkInt)
regs[ra].intVal = nb.intVal
of nkFloatLit..nkFloat64Lit:
ensureKind(rkFloat)
regs[ra].floatVal = nb.floatVal
else:
ensureKind(rkNode)
regs[ra].node = nb
of opcLdArr:
# a = b[c]
decodeBC(rkNode)
if regs[rc].intVal > high(int):
stackTrace(c, tos, pc, formatErrorIndexBound(regs[rc].intVal, high(int)))
let idx = regs[rc].intVal.int
let src = regs[rb].node
if src.kind in {nkStrLit..nkTripleStrLit}:
if idx <% src.strVal.len:
regs[ra].node = newNodeI(nkCharLit, c.debug[pc])
regs[ra].node.intVal = src.strVal[idx].ord
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, src.strVal.len-1))
elif src.kind notin {nkEmpty..nkFloat128Lit} and idx <% src.len:
regs[ra].node = src[idx]
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, src.safeLen-1))
of opcLdArrAddr:
# a = addr(b[c])
decodeBC(rkNodeAddr)
if regs[rc].intVal > high(int):
stackTrace(c, tos, pc, formatErrorIndexBound(regs[rc].intVal, high(int)))
let idx = regs[rc].intVal.int
let src = if regs[rb].kind == rkNode: regs[rb].node else: regs[rb].nodeAddr[]
if src.kind notin {nkEmpty..nkTripleStrLit} and idx <% src.len:
regs[ra].nodeAddr = addr src.sons[idx]
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, src.safeLen-1))
of opcLdStrIdx:
decodeBC(rkInt)
let idx = regs[rc].intVal.int
let s = regs[rb].node.strVal
if idx <% s.len:
regs[ra].intVal = s[idx].ord
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, s.len-1))
of opcLdStrIdxAddr:
# a = addr(b[c]); similar to opcLdArrAddr
decodeBC(rkNode)
if regs[rc].intVal > high(int):
stackTrace(c, tos, pc, formatErrorIndexBound(regs[rc].intVal, high(int)))
let idx = regs[rc].intVal.int
let s = regs[rb].node.strVal.addr # or `byaddr`
if idx <% s[].len:
# `makePtrType` not accessible from vm.nim
let typ = newType(tyPtr, nextTypeId c.idgen, c.module.owner)
typ.add getSysType(c.graph, c.debug[pc], tyChar)
let node = newNodeIT(nkIntLit, c.debug[pc], typ) # xxx nkPtrLit
node.intVal = cast[int](s[][idx].addr)
node.flags.incl nfIsPtr
regs[ra].node = node
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, s[].len-1))
of opcWrArr:
# a[b] = c
decodeBC(rkNode)
let idx = regs[rb].intVal.int
let arr = regs[ra].node
if arr.kind in {nkStrLit..nkTripleStrLit}:
if idx <% arr.strVal.len:
arr.strVal[idx] = chr(regs[rc].intVal)
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, arr.strVal.len-1))
elif idx <% arr.len:
writeField(arr[idx], regs[rc])
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, arr.safeLen-1))
of opcLdObj:
# a = b.c
decodeBC(rkNode)
let src = if regs[rb].kind == rkNode: regs[rb].node else: regs[rb].nodeAddr[]
case src.kind
of nkEmpty..nkNilLit:
# for nkPtrLit, this could be supported in the future, use something like:
# derefPtrToReg(src.intVal + offsetof(src.typ, rc), typ_field, regs[ra], isAssign = false)
# where we compute the offset in bytes for field rc
stackTrace(c, tos, pc, errNilAccess & " " & $("kind", src.kind, "typ", typeToString(src.typ), "rc", rc))
of nkObjConstr:
let n = src[rc + 1].skipColon
regs[ra].node = n
else:
let n = src[rc]
regs[ra].node = n
of opcLdObjAddr:
# a = addr(b.c)
decodeBC(rkNodeAddr)
let src = if regs[rb].kind == rkNode: regs[rb].node else: regs[rb].nodeAddr[]
case src.kind
of nkEmpty..nkNilLit:
stackTrace(c, tos, pc, errNilAccess)
of nkObjConstr:
let n = src.sons[rc + 1]
if n.kind == nkExprColonExpr:
regs[ra].nodeAddr = addr n.sons[1]
else:
regs[ra].nodeAddr = addr src.sons[rc + 1]
else:
regs[ra].nodeAddr = addr src.sons[rc]
of opcWrObj:
# a.b = c
decodeBC(rkNode)
assert regs[ra].node != nil
let shiftedRb = rb + ord(regs[ra].node.kind == nkObjConstr)
let dest = regs[ra].node
if dest.kind == nkNilLit:
stackTrace(c, tos, pc, errNilAccess)
elif dest[shiftedRb].kind == nkExprColonExpr:
writeField(dest[shiftedRb][1], regs[rc])
else:
writeField(dest[shiftedRb], regs[rc])
of opcWrStrIdx:
decodeBC(rkNode)
let idx = regs[rb].intVal.int
if idx <% regs[ra].node.strVal.len:
regs[ra].node.strVal[idx] = chr(regs[rc].intVal)
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, regs[ra].node.strVal.len-1))
of opcAddrReg:
decodeB(rkRegisterAddr)
regs[ra].regAddr = addr(regs[rb])
of opcAddrNode:
decodeB(rkNodeAddr)
case regs[rb].kind
of rkNode:
regs[ra].nodeAddr = addr(regs[rb].node)
of rkNodeAddr: # bug #14339
regs[ra].nodeAddr = regs[rb].nodeAddr
else:
stackTrace(c, tos, pc, "limited VM support for 'addr', got kind: " & $regs[rb].kind)
of opcLdDeref:
# a = b[]
let ra = instr.regA
let rb = instr.regB
case regs[rb].kind
of rkNodeAddr:
ensureKind(rkNode)
regs[ra].node = regs[rb].nodeAddr[]
of rkRegisterAddr:
ensureKind(regs[rb].regAddr.kind)
regs[ra] = regs[rb].regAddr[]
of rkNode:
if regs[rb].node.kind == nkRefTy:
regs[ra].node = regs[rb].node[0]
elif not maybeHandlePtr(regs[rb].node, regs[ra], false):
## e.g.: typ.kind = tyObject
ensureKind(rkNode)
regs[ra].node = regs[rb].node
else:
stackTrace(c, tos, pc, errNilAccess & " kind: " & $regs[rb].kind)
of opcWrDeref:
# a[] = c; b unused
let ra = instr.regA
let rc = instr.regC
case regs[ra].kind
of rkNodeAddr:
let n = regs[rc].regToNode
# `var object` parameters are sent as rkNodeAddr. When they are mutated
# vmgen generates opcWrDeref, which means that we must dereference
# twice.
# TODO: This should likely be handled differently in vmgen.
if (nfIsRef notin regs[ra].nodeAddr[].flags and
nfIsRef notin n.flags):
regs[ra].nodeAddr[][] = n[]
else:
regs[ra].nodeAddr[] = n
of rkRegisterAddr: regs[ra].regAddr[] = regs[rc]
of rkNode:
# xxx: also check for nkRefTy as in opcLdDeref?
if not maybeHandlePtr(regs[ra].node, regs[rc], true):
regs[ra].node[] = regs[rc].regToNode[]
regs[ra].node.flags.incl nfIsRef
else: stackTrace(c, tos, pc, errNilAccess)
of opcAddInt:
decodeBC(rkInt)
let
bVal = regs[rb].intVal
cVal = regs[rc].intVal
sum = bVal +% cVal
if (sum xor bVal) >= 0 or (sum xor cVal) >= 0:
regs[ra].intVal = sum
else:
stackTrace(c, tos, pc, errOverOrUnderflow)
of opcAddImmInt:
decodeBImm(rkInt)
#message(c.config, c.debug[pc], warnUser, "came here")
#debug regs[rb].node
let
bVal = regs[rb].intVal
cVal = imm
sum = bVal +% cVal
if (sum xor bVal) >= 0 or (sum xor cVal) >= 0:
regs[ra].intVal = sum
else:
stackTrace(c, tos, pc, errOverOrUnderflow)
of opcSubInt:
decodeBC(rkInt)
let
bVal = regs[rb].intVal
cVal = regs[rc].intVal
diff = bVal -% cVal
if (diff xor bVal) >= 0 or (diff xor not cVal) >= 0:
regs[ra].intVal = diff
else:
stackTrace(c, tos, pc, errOverOrUnderflow)
of opcSubImmInt:
decodeBImm(rkInt)
let
bVal = regs[rb].intVal
cVal = imm
diff = bVal -% cVal
if (diff xor bVal) >= 0 or (diff xor not cVal) >= 0:
regs[ra].intVal = diff
else:
stackTrace(c, tos, pc, errOverOrUnderflow)
of opcLenSeq:
decodeBImm(rkInt)
#assert regs[rb].kind == nkBracket
let high = (imm and 1) # discard flags
if (imm and nimNodeFlag) != 0:
# used by mNLen (NimNode.len)
regs[ra].intVal = regs[rb].node.safeLen - high
else:
# safeArrLen also return string node len
# used when string is passed as openArray in VM
regs[ra].intVal = regs[rb].node.safeArrLen - high
of opcLenStr:
decodeBImm(rkInt)
assert regs[rb].kind == rkNode
regs[ra].intVal = regs[rb].node.strVal.len - imm
of opcLenCstring:
decodeBImm(rkInt)
assert regs[rb].kind == rkNode
regs[ra].intVal = regs[rb].node.strVal.cstring.len - imm
of opcIncl:
decodeB(rkNode)
let b = regs[rb].regToNode
if not inSet(regs[ra].node, b):
regs[ra].node.add copyTree(b)
of opcInclRange:
decodeBC(rkNode)
var r = newNode(nkRange)
r.add regs[rb].regToNode
r.add regs[rc].regToNode
regs[ra].node.add r.copyTree
of opcExcl:
decodeB(rkNode)
var b = newNodeIT(nkCurly, regs[ra].node.info, regs[ra].node.typ)
b.add regs[rb].regToNode
var r = diffSets(c.config, regs[ra].node, b)
discardSons(regs[ra].node)
for i in 0..<r.len: regs[ra].node.add r[i]
of opcCard:
decodeB(rkInt)
regs[ra].intVal = nimsets.cardSet(c.config, regs[rb].node)
of opcMulInt:
decodeBC(rkInt)
let
bVal = regs[rb].intVal
cVal = regs[rc].intVal
product = bVal *% cVal
floatProd = toBiggestFloat(bVal) * toBiggestFloat(cVal)
resAsFloat = toBiggestFloat(product)
if resAsFloat == floatProd:
regs[ra].intVal = product
elif 32.0 * abs(resAsFloat - floatProd) <= abs(floatProd):
regs[ra].intVal = product
else:
stackTrace(c, tos, pc, errOverOrUnderflow)
of opcDivInt:
decodeBC(rkInt)
if regs[rc].intVal == 0: stackTrace(c, tos, pc, errConstantDivisionByZero)
else: regs[ra].intVal = regs[rb].intVal div regs[rc].intVal
of opcModInt:
decodeBC(rkInt)
if regs[rc].intVal == 0: stackTrace(c, tos, pc, errConstantDivisionByZero)
else: regs[ra].intVal = regs[rb].intVal mod regs[rc].intVal
of opcAddFloat:
decodeBC(rkFloat)
regs[ra].floatVal = regs[rb].floatVal + regs[rc].floatVal
of opcSubFloat:
decodeBC(rkFloat)
regs[ra].floatVal = regs[rb].floatVal - regs[rc].floatVal
of opcMulFloat:
decodeBC(rkFloat)
regs[ra].floatVal = regs[rb].floatVal * regs[rc].floatVal
of opcDivFloat:
decodeBC(rkFloat)
regs[ra].floatVal = regs[rb].floatVal / regs[rc].floatVal
of opcShrInt:
decodeBC(rkInt)
let b = cast[uint64](regs[rb].intVal)
let c = cast[uint64](regs[rc].intVal)
let a = cast[int64](b shr c)
regs[ra].intVal = a
of opcShlInt:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal shl regs[rc].intVal
of opcAshrInt:
decodeBC(rkInt)
regs[ra].intVal = ashr(regs[rb].intVal, regs[rc].intVal)
of opcBitandInt:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal and regs[rc].intVal
of opcBitorInt:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal or regs[rc].intVal
of opcBitxorInt:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal xor regs[rc].intVal
of opcAddu:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal +% regs[rc].intVal
of opcSubu:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal -% regs[rc].intVal
of opcMulu:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal *% regs[rc].intVal
of opcDivu:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal /% regs[rc].intVal
of opcModu:
decodeBC(rkInt)
regs[ra].intVal = regs[rb].intVal %% regs[rc].intVal
of opcEqInt:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].intVal == regs[rc].intVal)
of opcLeInt:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].intVal <= regs[rc].intVal)
of opcLtInt:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].intVal < regs[rc].intVal)
of opcEqFloat:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].floatVal == regs[rc].floatVal)
of opcLeFloat:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].floatVal <= regs[rc].floatVal)
of opcLtFloat:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].floatVal < regs[rc].floatVal)
of opcLeu:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].intVal <=% regs[rc].intVal)
of opcLtu:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].intVal <% regs[rc].intVal)
of opcEqRef:
var ret = false
decodeBC(rkInt)
template getTyp(n): untyped =
n.typ.skipTypes(abstractInst)
proc ptrEquality(n1: ptr PNode, n2: PNode): bool =
## true if n2.intVal represents a ptr equal to n1
let p1 = cast[int](n1)
case n2.kind
of nkNilLit: return p1 == 0
of nkIntLit: # TODO: nkPtrLit
# for example, n1.kind == nkFloatLit (ptr float)
# the problem is that n1.typ == nil so we can't compare n1.typ and n2.typ
# this is the best we can do (pending making sure we assign a valid n1.typ to nodeAddr's)
let t2 = n2.getTyp
return t2.kind in PtrLikeKinds and n2.intVal == p1
else: return false
if regs[rb].kind == rkNodeAddr:
if regs[rc].kind == rkNodeAddr:
ret = regs[rb].nodeAddr == regs[rc].nodeAddr
else:
ret = ptrEquality(regs[rb].nodeAddr, regs[rc].node)
elif regs[rc].kind == rkNodeAddr:
ret = ptrEquality(regs[rc].nodeAddr, regs[rb].node)
else:
let nb = regs[rb].node
let nc = regs[rc].node
if nb.kind != nc.kind: discard
elif (nb == nc) or (nb.kind == nkNilLit): ret = true # intentional
elif nb.kind in {nkSym, nkTupleConstr, nkClosure} and nb.typ != nil and nb.typ.kind == tyProc and sameConstant(nb, nc):
ret = true
# this also takes care of procvar's, represented as nkTupleConstr, e.g. (nil, nil)
elif nb.kind == nkIntLit and nc.kind == nkIntLit and nb.intVal == nc.intVal: # TODO: nkPtrLit
let tb = nb.getTyp
let tc = nc.getTyp
ret = tb.kind in PtrLikeKinds and tc.kind == tb.kind
regs[ra].intVal = ord(ret)
of opcEqNimNode:
decodeBC(rkInt)
regs[ra].intVal =
ord(exprStructuralEquivalent(regs[rb].node, regs[rc].node,
strictSymEquality=true))
of opcSameNodeType:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].node.typ.sameTypeOrNil regs[rc].node.typ)
of opcXor:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].intVal != regs[rc].intVal)
of opcNot:
decodeB(rkInt)
assert regs[rb].kind == rkInt
regs[ra].intVal = 1 - regs[rb].intVal
of opcUnaryMinusInt:
decodeB(rkInt)
assert regs[rb].kind == rkInt
let val = regs[rb].intVal
if val != int64.low:
regs[ra].intVal = -val
else:
stackTrace(c, tos, pc, errOverOrUnderflow)
of opcUnaryMinusFloat:
decodeB(rkFloat)
assert regs[rb].kind == rkFloat
regs[ra].floatVal = -regs[rb].floatVal
of opcBitnotInt:
decodeB(rkInt)
assert regs[rb].kind == rkInt
regs[ra].intVal = not regs[rb].intVal
of opcEqStr:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].node.strVal == regs[rc].node.strVal)
of opcLeStr:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].node.strVal <= regs[rc].node.strVal)
of opcLtStr:
decodeBC(rkInt)
regs[ra].intVal = ord(regs[rb].node.strVal < regs[rc].node.strVal)
of opcLeSet:
decodeBC(rkInt)
regs[ra].intVal = ord(containsSets(c.config, regs[rb].node, regs[rc].node))
of opcEqSet:
decodeBC(rkInt)
regs[ra].intVal = ord(equalSets(c.config, regs[rb].node, regs[rc].node))
of opcLtSet:
decodeBC(rkInt)
let a = regs[rb].node
let b = regs[rc].node
regs[ra].intVal = ord(containsSets(c.config, a, b) and not equalSets(c.config, a, b))
of opcMulSet:
decodeBC(rkNode)
createSet(regs[ra])
move(regs[ra].node.sons,
nimsets.intersectSets(c.config, regs[rb].node, regs[rc].node).sons)
of opcPlusSet:
decodeBC(rkNode)
createSet(regs[ra])
move(regs[ra].node.sons,
nimsets.unionSets(c.config, regs[rb].node, regs[rc].node).sons)
of opcMinusSet:
decodeBC(rkNode)
createSet(regs[ra])
move(regs[ra].node.sons,
nimsets.diffSets(c.config, regs[rb].node, regs[rc].node).sons)
of opcConcatStr:
decodeBC(rkNode)
createStr regs[ra]
regs[ra].node.strVal = getstr(regs[rb])
for i in rb+1..rb+rc-1:
regs[ra].node.strVal.add getstr(regs[i])
of opcAddStrCh:
decodeB(rkNode)
regs[ra].node.strVal.add(regs[rb].intVal.chr)
of opcAddStrStr:
decodeB(rkNode)
regs[ra].node.strVal.add(regs[rb].node.strVal)
of opcAddSeqElem:
decodeB(rkNode)
if regs[ra].node.kind == nkBracket:
regs[ra].node.add(copyValue(regs[rb].regToNode))
else:
stackTrace(c, tos, pc, errNilAccess)
of opcGetImpl:
decodeB(rkNode)
var a = regs[rb].node
if a.kind == nkVarTy: a = a[0]
if a.kind == nkSym:
regs[ra].node = if a.sym.ast.isNil: newNode(nkNilLit)
else: copyTree(a.sym.ast)
regs[ra].node.flags.incl nfIsRef
else:
stackTrace(c, tos, pc, "node is not a symbol")
of opcGetImplTransf:
decodeB(rkNode)
let a = regs[rb].node
if a.kind == nkSym:
regs[ra].node =
if a.sym.ast.isNil:
newNode(nkNilLit)
else:
let ast = a.sym.ast.shallowCopy
for i in 0..<a.sym.ast.len:
ast[i] = a.sym.ast[i]
ast[bodyPos] = transformBody(c.graph, c.idgen, a.sym, cache=true)
ast.copyTree()
of opcSymOwner:
decodeB(rkNode)
let a = regs[rb].node
if a.kind == nkSym:
regs[ra].node = if a.sym.owner.isNil: newNode(nkNilLit)
else: newSymNode(a.sym.skipGenericOwner)
regs[ra].node.flags.incl nfIsRef
else:
stackTrace(c, tos, pc, "node is not a symbol")
of opcSymIsInstantiationOf:
decodeBC(rkInt)
let a = regs[rb].node
let b = regs[rc].node
if a.kind == nkSym and a.sym.kind in skProcKinds and
b.kind == nkSym and b.sym.kind in skProcKinds:
regs[ra].intVal =
if sfFromGeneric in a.sym.flags and a.sym.owner == b.sym: 1
else: 0
else:
stackTrace(c, tos, pc, "node is not a proc symbol")
of opcEcho:
let rb = instr.regB
template fn(s) = msgWriteln(c.config, s, {msgStdout, msgNoUnitSep})
if rb == 1: fn(regs[ra].node.strVal)
else:
var outp = ""
for i in ra..ra+rb-1:
#if regs[i].kind != rkNode: debug regs[i]
outp.add(regs[i].node.strVal)
fn(outp)
of opcContainsSet:
decodeBC(rkInt)
regs[ra].intVal = ord(inSet(regs[rb].node, regs[rc].regToNode))
of opcSubStr:
decodeBC(rkNode)
inc pc
assert c.code[pc].opcode == opcSubStr
let rd = c.code[pc].regA
createStr regs[ra]
regs[ra].node.strVal = substr(regs[rb].node.strVal,
regs[rc].intVal.int, regs[rd].intVal.int)
of opcParseFloat:
decodeBC(rkInt)
inc pc
assert c.code[pc].opcode == opcParseFloat
let rd = c.code[pc].regA
var rcAddr = addr(regs[rc])
if rcAddr.kind == rkRegisterAddr: rcAddr = rcAddr.regAddr
elif regs[rc].kind != rkFloat:
regs[rc] = TFullReg(kind: rkFloat)
regs[ra].intVal = parseBiggestFloat(regs[rb].node.strVal,
rcAddr.floatVal, regs[rd].intVal.int)
of opcRangeChck:
let rb = instr.regB
let rc = instr.regC
if not (leValueConv(regs[rb].regToNode, regs[ra].regToNode) and
leValueConv(regs[ra].regToNode, regs[rc].regToNode)):
stackTrace(c, tos, pc,
errIllegalConvFromXtoY % [
$regs[ra].regToNode, "[" & $regs[rb].regToNode & ".." & $regs[rc].regToNode & "]"])
of opcIndCall, opcIndCallAsgn:
# dest = call regStart, n; where regStart = fn, arg1, ...
let rb = instr.regB
let rc = instr.regC
let bb = regs[rb].node
let isClosure = bb.kind == nkTupleConstr
let prc = if not isClosure: bb.sym else: bb[0].sym
if prc.offset < -1:
# it's a callback:
c.callbacks[-prc.offset-2].value(
VmArgs(ra: ra, rb: rb, rc: rc, slots: cast[ptr UncheckedArray[TFullReg]](addr regs[0]),
currentException: c.currentExceptionA,
currentLineInfo: c.debug[pc]))
elif importcCond(c, prc):
if compiletimeFFI notin c.config.features:
globalError(c.config, c.debug[pc], "VM not allowed to do FFI, see `compiletimeFFI`")
# we pass 'tos.slots' instead of 'regs' so that the compiler can keep
# 'regs' in a register:
when hasFFI:
if prc.position - 1 < 0:
globalError(c.config, c.debug[pc],
"VM call invalid: prc.position: " & $prc.position)
let prcValue = c.globals[prc.position-1]
if prcValue.kind == nkEmpty:
globalError(c.config, c.debug[pc], "cannot run " & prc.name.s)
var slots2: TNodeSeq
slots2.setLen(tos.slots.len)
for i in 0..<tos.slots.len:
slots2[i] = regToNode(tos.slots[i])
let newValue = callForeignFunction(c.config, prcValue, prc.typ, slots2,
rb+1, rc-1, c.debug[pc])
if newValue.kind != nkEmpty:
assert instr.opcode == opcIndCallAsgn
putIntoReg(regs[ra], newValue)
else:
globalError(c.config, c.debug[pc], "VM not built with FFI support")
elif prc.kind != skTemplate:
let newPc = compile(c, prc)
# tricky: a recursion is also a jump back, so we use the same
# logic as for loops:
if newPc < pc: handleJmpBack()
#echo "new pc ", newPc, " calling: ", prc.name.s
var newFrame = PStackFrame(prc: prc, comesFrom: pc, next: tos)
newSeq(newFrame.slots, prc.offset+ord(isClosure))
if not isEmptyType(prc.typ[0]):
putIntoReg(newFrame.slots[0], getNullValue(prc.typ[0], prc.info, c.config))
for i in 1..rc-1:
newFrame.slots[i] = regs[rb+i]
if isClosure:
newFrame.slots[rc] = TFullReg(kind: rkNode, node: regs[rb].node[1])
tos = newFrame
updateRegsAlias
# -1 for the following 'inc pc'
pc = newPc-1
else:
# for 'getAst' support we need to support template expansion here:
let genSymOwner = if tos.next != nil and tos.next.prc != nil:
tos.next.prc
else:
c.module
var macroCall = newNodeI(nkCall, c.debug[pc])
macroCall.add(newSymNode(prc))
for i in 1..rc-1:
let node = regs[rb+i].regToNode
node.info = c.debug[pc]
macroCall.add(node)
var a = evalTemplate(macroCall, prc, genSymOwner, c.config, c.cache, c.templInstCounter, c.idgen)
if a.kind == nkStmtList and a.len == 1: a = a[0]
a.recSetFlagIsRef
ensureKind(rkNode)
regs[ra].node = a
of opcTJmp:
# jump Bx if A != 0
let rbx = instr.regBx - wordExcess - 1 # -1 for the following 'inc pc'
if regs[ra].intVal != 0:
inc pc, rbx
of opcFJmp:
# jump Bx if A == 0
let rbx = instr.regBx - wordExcess - 1 # -1 for the following 'inc pc'
if regs[ra].intVal == 0:
inc pc, rbx
of opcJmp:
# jump Bx
let rbx = instr.regBx - wordExcess - 1 # -1 for the following 'inc pc'
inc pc, rbx
of opcJmpBack:
let rbx = instr.regBx - wordExcess - 1 # -1 for the following 'inc pc'
inc pc, rbx
handleJmpBack()
of opcBranch:
# we know the next instruction is a 'fjmp':
let branch = c.constants[instr.regBx-wordExcess]
var cond = false
for j in 0..<branch.len - 1:
if overlap(regs[ra].regToNode, branch[j]):
cond = true
break
assert c.code[pc+1].opcode == opcFJmp
inc pc
# we skip this instruction so that the final 'inc(pc)' skips
# the following jump
if not cond:
let instr2 = c.code[pc]
let rbx = instr2.regBx - wordExcess - 1 # -1 for the following 'inc pc'
inc pc, rbx
of opcTry:
let rbx = instr.regBx - wordExcess
tos.pushSafePoint(pc + rbx)
assert c.code[pc+rbx].opcode in {opcExcept, opcFinally}
of opcExcept:
# This opcode is never executed, it only holds information for the
# exception handling routines.
doAssert(false)
of opcFinally:
# Pop the last safepoint introduced by a opcTry. This opcode is only
# executed _iff_ no exception was raised in the body of the `try`
# statement hence the need to pop the safepoint here.
doAssert(savedPC < 0)
tos.popSafePoint()
of opcFinallyEnd:
# The control flow may not resume at the next instruction since we may be
# raising an exception or performing a cleanup.
if savedPC >= 0:
pc = savedPC - 1
savedPC = -1
if tos != savedFrame:
tos = savedFrame
updateRegsAlias
of opcRaise:
let raised =
# Empty `raise` statement - reraise current exception
if regs[ra].kind == rkNone:
c.currentExceptionA
else:
regs[ra].node
c.currentExceptionA = raised
# Set the `name` field of the exception
c.currentExceptionA[2].skipColon.strVal = c.currentExceptionA.typ.sym.name.s
c.exceptionInstr = pc
var frame = tos
var jumpTo = findExceptionHandler(c, frame, raised)
while jumpTo.why == ExceptionGotoUnhandled and not frame.next.isNil:
frame = frame.next
jumpTo = findExceptionHandler(c, frame, raised)
case jumpTo.why:
of ExceptionGotoHandler:
# Jump to the handler, do nothing when the `finally` block ends.
savedPC = -1
pc = jumpTo.where - 1
if tos != frame:
tos = frame
updateRegsAlias
of ExceptionGotoFinally:
# Jump to the `finally` block first then re-jump here to continue the
# traversal of the exception chain
savedPC = pc
savedFrame = tos
pc = jumpTo.where - 1
if tos != frame:
tos = frame
updateRegsAlias
of ExceptionGotoUnhandled:
# Nobody handled this exception, error out.
bailOut(c, tos)
of opcNew:
ensureKind(rkNode)
let typ = c.types[instr.regBx - wordExcess]
regs[ra].node = getNullValue(typ, c.debug[pc], c.config)
regs[ra].node.flags.incl nfIsRef
of opcNewSeq:
let typ = c.types[instr.regBx - wordExcess]
inc pc
ensureKind(rkNode)
let instr2 = c.code[pc]
let count = regs[instr2.regA].intVal.int
regs[ra].node = newNodeI(nkBracket, c.debug[pc])
regs[ra].node.typ = typ
newSeq(regs[ra].node.sons, count)
for i in 0..<count:
regs[ra].node[i] = getNullValue(typ[0], c.debug[pc], c.config)
of opcNewStr:
decodeB(rkNode)
regs[ra].node = newNodeI(nkStrLit, c.debug[pc])
regs[ra].node.strVal = newString(regs[rb].intVal.int)
of opcLdImmInt:
# dest = immediate value
decodeBx(rkInt)
regs[ra].intVal = rbx
of opcLdNull:
ensureKind(rkNode)
let typ = c.types[instr.regBx - wordExcess]
regs[ra].node = getNullValue(typ, c.debug[pc], c.config)
# opcLdNull really is the gist of the VM's problems: should it load
# a fresh null to regs[ra].node or to regs[ra].node[]? This really
# depends on whether regs[ra] represents the variable itself or whether
# it holds the indirection! Due to the way registers are re-used we cannot
# say for sure here! --> The codegen has to deal with it
# via 'genAsgnPatch'.
of opcLdNullReg:
let typ = c.types[instr.regBx - wordExcess]
if typ.skipTypes(abstractInst+{tyRange}-{tyTypeDesc}).kind in {
tyFloat..tyFloat128}:
ensureKind(rkFloat)
regs[ra].floatVal = 0.0
else:
ensureKind(rkInt)
regs[ra].intVal = 0
of opcLdConst:
let rb = instr.regBx - wordExcess
let cnst = c.constants[rb]
if fitsRegister(cnst.typ):
reset(regs[ra])
putIntoReg(regs[ra], cnst)
else:
ensureKind(rkNode)
regs[ra].node = cnst
of opcAsgnConst:
let rb = instr.regBx - wordExcess
let cnst = c.constants[rb]
if fitsRegister(cnst.typ):
putIntoReg(regs[ra], cnst)
else:
ensureKind(rkNode)
regs[ra].node = cnst.copyTree
of opcLdGlobal:
let rb = instr.regBx - wordExcess - 1
ensureKind(rkNode)
regs[ra].node = c.globals[rb]
of opcLdGlobalDerefFFI:
let rb = instr.regBx - wordExcess - 1
let node = c.globals[rb]
let typ = node.typ
doAssert node.kind == nkIntLit, $(node.kind)
if typ.kind == tyPtr:
ensureKind(rkNode)
# use nkPtrLit once this is added
let node2 = newNodeIT(nkIntLit, c.debug[pc], typ)
node2.intVal = cast[ptr int](node.intVal)[]
node2.flags.incl nfIsPtr
regs[ra].node = node2
elif not derefPtrToReg(node.intVal, typ, regs[ra], isAssign = false):
stackTrace(c, tos, pc, "opcLdDeref unsupported type: " & $(typeToString(typ), typ[0].kind))
of opcLdGlobalAddrDerefFFI:
let rb = instr.regBx - wordExcess - 1
let node = c.globals[rb]
let typ = node.typ
var node2 = newNodeIT(nkIntLit, node.info, typ)
node2.intVal = node.intVal
node2.flags.incl nfIsPtr
ensureKind(rkNode)
regs[ra].node = node2
of opcLdGlobalAddr:
let rb = instr.regBx - wordExcess - 1
ensureKind(rkNodeAddr)
regs[ra].nodeAddr = addr(c.globals[rb])
of opcRepr:
decodeB(rkNode)
createStr regs[ra]
regs[ra].node.strVal = renderTree(regs[rb].regToNode, {renderNoComments, renderDocComments})
of opcQuit:
if c.mode in {emRepl, emStaticExpr, emStaticStmt}:
message(c.config, c.debug[pc], hintQuitCalled)
msgQuit(int8(toInt(getOrdValue(regs[ra].regToNode, onError = toInt128(1)))))
else:
return TFullReg(kind: rkNone)
of opcInvalidField:
stackTrace(c, tos, pc, errFieldXNotFound & regs[ra].node.strVal)
of opcSetLenStr:
decodeB(rkNode)
#createStrKeepNode regs[ra]
regs[ra].node.strVal.setLen(regs[rb].intVal.int)
of opcOf:
decodeBC(rkInt)
let typ = c.types[regs[rc].intVal.int]
regs[ra].intVal = ord(inheritanceDiff(regs[rb].node.typ, typ) <= 0)
of opcIs:
decodeBC(rkInt)
let t1 = regs[rb].node.typ.skipTypes({tyTypeDesc})
let t2 = c.types[regs[rc].intVal.int]
# XXX: This should use the standard isOpImpl
let match = if t2.kind == tyUserTypeClass: true
else: sameType(t1, t2)
regs[ra].intVal = ord(match)
of opcSetLenSeq:
decodeB(rkNode)
let newLen = regs[rb].intVal.int
if regs[ra].node.isNil: stackTrace(c, tos, pc, errNilAccess)
else: c.setLenSeq(regs[ra].node, newLen, c.debug[pc])
of opcNarrowS:
decodeB(rkInt)
let min = -(1.BiggestInt shl (rb-1))
let max = (1.BiggestInt shl (rb-1))-1
if regs[ra].intVal < min or regs[ra].intVal > max:
stackTrace(c, tos, pc, "unhandled exception: value out of range")
of opcNarrowU:
decodeB(rkInt)
regs[ra].intVal = regs[ra].intVal and ((1'i64 shl rb)-1)
of opcSignExtend:
# like opcNarrowS, but no out of range possible
decodeB(rkInt)
let imm = 64 - rb
regs[ra].intVal = ashr(regs[ra].intVal shl imm, imm)
of opcIsNil:
decodeB(rkInt)
let node = regs[rb].node
regs[ra].intVal = ord(
# Note that `nfIsRef` + `nkNilLit` represents an allocated
# reference with the value `nil`, so `isNil` should be false!
(node.kind == nkNilLit and nfIsRef notin node.flags) or
(not node.typ.isNil and node.typ.kind == tyProc and
node.typ.callConv == ccClosure and node.safeLen > 0 and
node[0].kind == nkNilLit and node[1].kind == nkNilLit))
of opcNBindSym:
# cannot use this simple check
# if dynamicBindSym notin c.config.features:
# bindSym with static input
decodeBx(rkNode)
regs[ra].node = copyTree(c.constants[rbx])
regs[ra].node.flags.incl nfIsRef
of opcNDynBindSym:
# experimental bindSym
let
rb = instr.regB
rc = instr.regC
idx = int(regs[rb+rc-1].intVal)
callback = c.callbacks[idx].value
args = VmArgs(ra: ra, rb: rb, rc: rc, slots: cast[ptr UncheckedArray[TFullReg]](addr regs[0]),
currentException: c.currentExceptionA,
currentLineInfo: c.debug[pc])
callback(args)
regs[ra].node.flags.incl nfIsRef
of opcNChild:
decodeBC(rkNode)
let idx = regs[rc].intVal.int
let src = regs[rb].node
if src.kind in {nkEmpty..nkNilLit}:
stackTrace(c, tos, pc, "cannot get child of node kind: n" & $src.kind)
elif idx >=% src.len:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, src.len-1))
else:
regs[ra].node = src[idx]
of opcNSetChild:
decodeBC(rkNode)
let idx = regs[rb].intVal.int
var dest = regs[ra].node
if nfSem in dest.flags and allowSemcheckedAstModification notin c.config.legacyFeatures:
stackTrace(c, tos, pc, "typechecked nodes may not be modified")
elif dest.kind in {nkEmpty..nkNilLit}:
stackTrace(c, tos, pc, "cannot set child of node kind: n" & $dest.kind)
elif idx >=% dest.len:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, dest.len-1))
else:
dest[idx] = regs[rc].node
of opcNAdd:
decodeBC(rkNode)
var u = regs[rb].node
if nfSem in u.flags and allowSemcheckedAstModification notin c.config.legacyFeatures:
stackTrace(c, tos, pc, "typechecked nodes may not be modified")
elif u.kind in {nkEmpty..nkNilLit}:
stackTrace(c, tos, pc, "cannot add to node kind: n" & $u.kind)
else:
u.add(regs[rc].node)
regs[ra].node = u
of opcNAddMultiple:
decodeBC(rkNode)
let x = regs[rc].node
var u = regs[rb].node
if nfSem in u.flags and allowSemcheckedAstModification notin c.config.legacyFeatures:
stackTrace(c, tos, pc, "typechecked nodes may not be modified")
elif u.kind in {nkEmpty..nkNilLit}:
stackTrace(c, tos, pc, "cannot add to node kind: n" & $u.kind)
else:
for i in 0..<x.len: u.add(x[i])
regs[ra].node = u
of opcNKind:
decodeB(rkInt)
regs[ra].intVal = ord(regs[rb].node.kind)
c.comesFromHeuristic = regs[rb].node.info
of opcNSymKind:
decodeB(rkInt)
let a = regs[rb].node
if a.kind == nkSym:
regs[ra].intVal = ord(a.sym.kind)
else:
stackTrace(c, tos, pc, "node is not a symbol")
c.comesFromHeuristic = regs[rb].node.info
of opcNIntVal:
decodeB(rkInt)
let a = regs[rb].node
if a.kind in {nkCharLit..nkUInt64Lit}:
regs[ra].intVal = a.intVal
elif a.kind == nkSym and a.sym.kind == skEnumField:
regs[ra].intVal = a.sym.position
else:
stackTrace(c, tos, pc, errFieldXNotFound & "intVal")
of opcNFloatVal:
decodeB(rkFloat)
let a = regs[rb].node
case a.kind
of nkFloatLit..nkFloat64Lit: regs[ra].floatVal = a.floatVal
else: stackTrace(c, tos, pc, errFieldXNotFound & "floatVal")
of opcNSymbol:
decodeB(rkNode)
let a = regs[rb].node
if a.kind == nkSym:
regs[ra].node = copyNode(a)
else:
stackTrace(c, tos, pc, errFieldXNotFound & "symbol")
of opcNIdent:
decodeB(rkNode)
let a = regs[rb].node
if a.kind == nkIdent:
regs[ra].node = copyNode(a)
else:
stackTrace(c, tos, pc, errFieldXNotFound & "ident")
of opcNodeId:
decodeB(rkInt)
when defined(useNodeIds):
regs[ra].intVal = regs[rb].node.id
else:
regs[ra].intVal = -1
of opcNGetType:
let rb = instr.regB
let rc = instr.regC
case rc
of 0:
# getType opcode:
ensureKind(rkNode)
if regs[rb].kind == rkNode and regs[rb].node.typ != nil:
regs[ra].node = opMapTypeToAst(c.cache, regs[rb].node.typ, c.debug[pc], c.idgen)
elif regs[rb].kind == rkNode and regs[rb].node.kind == nkSym and regs[rb].node.sym.typ != nil:
regs[ra].node = opMapTypeToAst(c.cache, regs[rb].node.sym.typ, c.debug[pc], c.idgen)
else:
stackTrace(c, tos, pc, "node has no type")
of 1:
# typeKind opcode:
ensureKind(rkInt)
if regs[rb].kind == rkNode and regs[rb].node.typ != nil:
regs[ra].intVal = ord(regs[rb].node.typ.kind)
elif regs[rb].kind == rkNode and regs[rb].node.kind == nkSym and regs[rb].node.sym.typ != nil:
regs[ra].intVal = ord(regs[rb].node.sym.typ.kind)
#else:
# stackTrace(c, tos, pc, "node has no type")
of 2:
# getTypeInst opcode:
ensureKind(rkNode)
if regs[rb].kind == rkNode and regs[rb].node.typ != nil:
regs[ra].node = opMapTypeInstToAst(c.cache, regs[rb].node.typ, c.debug[pc], c.idgen)
elif regs[rb].kind == rkNode and regs[rb].node.kind == nkSym and regs[rb].node.sym.typ != nil:
regs[ra].node = opMapTypeInstToAst(c.cache, regs[rb].node.sym.typ, c.debug[pc], c.idgen)
else:
stackTrace(c, tos, pc, "node has no type")
else:
# getTypeImpl opcode:
ensureKind(rkNode)
if regs[rb].kind == rkNode and regs[rb].node.typ != nil:
regs[ra].node = opMapTypeImplToAst(c.cache, regs[rb].node.typ, c.debug[pc], c.idgen)
elif regs[rb].kind == rkNode and regs[rb].node.kind == nkSym and regs[rb].node.sym.typ != nil:
regs[ra].node = opMapTypeImplToAst(c.cache, regs[rb].node.sym.typ, c.debug[pc], c.idgen)
else:
stackTrace(c, tos, pc, "node has no type")
of opcNGetSize:
decodeBImm(rkInt)
let n = regs[rb].node
case imm
of 0: # size
if n.typ == nil:
stackTrace(c, tos, pc, "node has no type")
else:
regs[ra].intVal = getSize(c.config, n.typ)
of 1: # align
if n.typ == nil:
stackTrace(c, tos, pc, "node has no type")
else:
regs[ra].intVal = getAlign(c.config, n.typ)
else: # offset
if n.kind != nkSym:
stackTrace(c, tos, pc, "node is not a symbol")
elif n.sym.kind != skField:
stackTrace(c, tos, pc, "symbol is not a field (nskField)")
else:
regs[ra].intVal = n.sym.offset
of opcNStrVal:
decodeB(rkNode)
createStr regs[ra]
let a = regs[rb].node
case a.kind
of nkStrLit..nkTripleStrLit:
regs[ra].node.strVal = a.strVal
of nkCommentStmt:
regs[ra].node.strVal = a.comment
of nkIdent:
regs[ra].node.strVal = a.ident.s
of nkSym:
regs[ra].node.strVal = a.sym.name.s
else:
stackTrace(c, tos, pc, errFieldXNotFound & "strVal")
of opcNSigHash:
decodeB(rkNode)
createStr regs[ra]
if regs[rb].node.kind != nkSym:
stackTrace(c, tos, pc, "node is not a symbol")
else:
regs[ra].node.strVal = $sigHash(regs[rb].node.sym)
of opcSlurp:
decodeB(rkNode)
createStr regs[ra]
regs[ra].node.strVal = opSlurp(regs[rb].node.strVal, c.debug[pc],
c.module, c.config)
of opcGorge:
decodeBC(rkNode)
inc pc
let rd = c.code[pc].regA
createStr regs[ra]
if defined(nimsuggest) or c.config.cmd == cmdCheck:
discard "don't run staticExec for 'nim suggest'"
regs[ra].node.strVal = ""
else:
when defined(nimcore):
regs[ra].node.strVal = opGorge(regs[rb].node.strVal,
regs[rc].node.strVal, regs[rd].node.strVal,
c.debug[pc], c.config)[0]
else:
regs[ra].node.strVal = ""
globalError(c.config, c.debug[pc], "VM is not built with 'gorge' support")
of opcNError, opcNWarning, opcNHint:
decodeB(rkNode)
let a = regs[ra].node
let b = regs[rb].node
let info = if b.kind == nkNilLit: c.debug[pc] else: b.info
if instr.opcode == opcNError:
stackTrace(c, tos, pc, a.strVal, info)
elif instr.opcode == opcNWarning:
message(c.config, info, warnUser, a.strVal)
elif instr.opcode == opcNHint:
message(c.config, info, hintUser, a.strVal)
of opcParseExprToAst:
decodeB(rkNode)
# c.debug[pc].line.int - countLines(regs[rb].strVal) ?
var error: string
let ast = parseString(regs[rb].node.strVal, c.cache, c.config,
toFullPath(c.config, c.debug[pc]), c.debug[pc].line.int,
proc (conf: ConfigRef; info: TLineInfo; msg: TMsgKind; arg: string) {.nosinks.} =
if error.len == 0 and msg <= errMax:
error = formatMsg(conf, info, msg, arg))
if error.len > 0:
c.errorFlag = error
elif ast.len != 1:
c.errorFlag = formatMsg(c.config, c.debug[pc], errGenerated,
"expected expression, but got multiple statements")
else:
regs[ra].node = ast[0]
of opcParseStmtToAst:
decodeB(rkNode)
var error: string
let ast = parseString(regs[rb].node.strVal, c.cache, c.config,
toFullPath(c.config, c.debug[pc]), c.debug[pc].line.int,
proc (conf: ConfigRef; info: TLineInfo; msg: TMsgKind; arg: string) {.nosinks.} =
if error.len == 0 and msg <= errMax:
error = formatMsg(conf, info, msg, arg))
if error.len > 0:
c.errorFlag = error
else:
regs[ra].node = ast
of opcQueryErrorFlag:
createStr regs[ra]
regs[ra].node.strVal = c.errorFlag
c.errorFlag.setLen 0
of opcCallSite:
ensureKind(rkNode)
if c.callsite != nil: regs[ra].node = c.callsite
else: stackTrace(c, tos, pc, errFieldXNotFound & "callsite")
of opcNGetLineInfo:
decodeBImm(rkNode)
let n = regs[rb].node
case imm
of 0: # getFile
regs[ra].node = newStrNode(nkStrLit, toFullPath(c.config, n.info))
of 1: # getLine
regs[ra].node = newIntNode(nkIntLit, n.info.line.int)
of 2: # getColumn
regs[ra].node = newIntNode(nkIntLit, n.info.col)
else:
internalAssert c.config, false
regs[ra].node.info = n.info
regs[ra].node.typ = n.typ
of opcNSetLineInfo:
decodeB(rkNode)
regs[ra].node.info = regs[rb].node.info
of opcEqIdent:
decodeBC(rkInt)
# aliases for shorter and easier to understand code below
var aNode = regs[rb].node
var bNode = regs[rc].node
# Skipping both, `nkPostfix` and `nkAccQuoted` for both
# arguments. `nkPostfix` exists only to tag exported symbols
# and therefor it can be safely skipped. Nim has no postfix
# operator. `nkAccQuoted` is used to quote an identifier that
# wouldn't be allowed to use in an unquoted context.
if aNode.kind == nkPostfix:
aNode = aNode[1]
if aNode.kind == nkAccQuoted:
aNode = aNode[0]
if bNode.kind == nkPostfix:
bNode = bNode[1]
if bNode.kind == nkAccQuoted:
bNode = bNode[0]
# These vars are of type `cstring` to prevent unnecessary string copy.
var aStrVal: cstring = nil
var bStrVal: cstring = nil
# extract strVal from argument ``a``
case aNode.kind
of nkStrLit..nkTripleStrLit:
aStrVal = aNode.strVal.cstring
of nkIdent:
aStrVal = aNode.ident.s.cstring
of nkSym:
aStrVal = aNode.sym.name.s.cstring
of nkOpenSymChoice, nkClosedSymChoice:
aStrVal = aNode[0].sym.name.s.cstring
else:
discard
# extract strVal from argument ``b``
case bNode.kind
of nkStrLit..nkTripleStrLit:
bStrVal = bNode.strVal.cstring
of nkIdent:
bStrVal = bNode.ident.s.cstring
of nkSym:
bStrVal = bNode.sym.name.s.cstring
of nkOpenSymChoice, nkClosedSymChoice:
bStrVal = bNode[0].sym.name.s.cstring
else:
discard
regs[ra].intVal =
if aStrVal != nil and bStrVal != nil:
ord(idents.cmpIgnoreStyle(aStrVal, bStrVal, high(int)) == 0)
else:
0
of opcStrToIdent:
decodeB(rkNode)
if regs[rb].node.kind notin {nkStrLit..nkTripleStrLit}:
stackTrace(c, tos, pc, errFieldXNotFound & "strVal")
else:
regs[ra].node = newNodeI(nkIdent, c.debug[pc])
regs[ra].node.ident = getIdent(c.cache, regs[rb].node.strVal)
regs[ra].node.flags.incl nfIsRef
of opcSetType:
let typ = c.types[instr.regBx - wordExcess]
if regs[ra].kind != rkNode:
let temp = regToNode(regs[ra])
ensureKind(rkNode)
regs[ra].node = temp
regs[ra].node.info = c.debug[pc]
regs[ra].node.typ = typ
of opcConv:
let rb = instr.regB
inc pc
let desttyp = c.types[c.code[pc].regBx - wordExcess]
inc pc
let srctyp = c.types[c.code[pc].regBx - wordExcess]
if opConv(c, regs[ra], regs[rb], desttyp, srctyp):
stackTrace(c, tos, pc,
errIllegalConvFromXtoY % [
typeToString(srctyp), typeToString(desttyp)])
of opcCast:
let rb = instr.regB
inc pc
let desttyp = c.types[c.code[pc].regBx - wordExcess]
inc pc
let srctyp = c.types[c.code[pc].regBx - wordExcess]
when hasFFI:
let dest = fficast(c.config, regs[rb].node, desttyp)
# todo: check whether this is correct
# asgnRef(regs[ra], dest)
putIntoReg(regs[ra], dest)
else:
globalError(c.config, c.debug[pc], "cannot evaluate cast")
of opcNSetIntVal:
decodeB(rkNode)
var dest = regs[ra].node
if dest.kind in {nkCharLit..nkUInt64Lit} and
regs[rb].kind in {rkInt}:
dest.intVal = regs[rb].intVal
elif dest.kind == nkSym and dest.sym.kind == skEnumField:
stackTrace(c, tos, pc, "`intVal` cannot be changed for an enum symbol.")
else:
stackTrace(c, tos, pc, errFieldXNotFound & "intVal")
of opcNSetFloatVal:
decodeB(rkNode)
var dest = regs[ra].node
if dest.kind in {nkFloatLit..nkFloat64Lit} and
regs[rb].kind in {rkFloat}:
dest.floatVal = regs[rb].floatVal
else:
stackTrace(c, tos, pc, errFieldXNotFound & "floatVal")
of opcNSetSymbol:
decodeB(rkNode)
var dest = regs[ra].node
if dest.kind == nkSym and regs[rb].node.kind == nkSym:
dest.sym = regs[rb].node.sym
else:
stackTrace(c, tos, pc, errFieldXNotFound & "symbol")
of opcNSetIdent:
decodeB(rkNode)
var dest = regs[ra].node
if dest.kind == nkIdent and regs[rb].node.kind == nkIdent:
dest.ident = regs[rb].node.ident
else:
stackTrace(c, tos, pc, errFieldXNotFound & "ident")
of opcNSetType:
decodeB(rkNode)
let b = regs[rb].node
internalAssert c.config, b.kind == nkSym and b.sym.kind == skType
internalAssert c.config, regs[ra].node != nil
regs[ra].node.typ = b.sym.typ
of opcNSetStrVal:
decodeB(rkNode)
var dest = regs[ra].node
if dest.kind in {nkStrLit..nkTripleStrLit} and
regs[rb].kind in {rkNode}:
dest.strVal = regs[rb].node.strVal
elif dest.kind == nkCommentStmt and regs[rb].kind in {rkNode}:
dest.comment = regs[rb].node.strVal
else:
stackTrace(c, tos, pc, errFieldXNotFound & "strVal")
of opcNNewNimNode:
decodeBC(rkNode)
var k = regs[rb].intVal
if k < 0 or k > ord(high(TNodeKind)):
internalError(c.config, c.debug[pc],
"request to create a NimNode of invalid kind")
let cc = regs[rc].node
let x = newNodeI(TNodeKind(int(k)),
if cc.kind != nkNilLit:
cc.info
elif c.comesFromHeuristic.line != 0'u16:
c.comesFromHeuristic
elif c.callsite != nil and c.callsite.safeLen > 1:
c.callsite[1].info
else:
c.debug[pc])
x.flags.incl nfIsRef
# prevent crashes in the compiler resulting from wrong macros:
if x.kind == nkIdent: x.ident = c.cache.emptyIdent
regs[ra].node = x
of opcNCopyNimNode:
decodeB(rkNode)
regs[ra].node = copyNode(regs[rb].node)
of opcNCopyNimTree:
decodeB(rkNode)
regs[ra].node = copyTree(regs[rb].node)
of opcNDel:
decodeBC(rkNode)
let bb = regs[rb].intVal.int
for i in 0..<regs[rc].intVal.int:
delSon(regs[ra].node, bb)
of opcGenSym:
decodeBC(rkNode)
let k = regs[rb].intVal
let name = if regs[rc].node.strVal.len == 0: ":tmp"
else: regs[rc].node.strVal
if k < 0 or k > ord(high(TSymKind)):
internalError(c.config, c.debug[pc], "request to create symbol of invalid kind")
var sym = newSym(k.TSymKind, getIdent(c.cache, name), nextSymId c.idgen, c.module.owner, c.debug[pc])
incl(sym.flags, sfGenSym)
regs[ra].node = newSymNode(sym)
regs[ra].node.flags.incl nfIsRef
of opcNccValue:
decodeB(rkInt)
let destKey = regs[rb].node.strVal
regs[ra].intVal = getOrDefault(c.graph.cacheCounters, destKey)
of opcNccInc:
let g = c.graph
declBC()
let destKey = regs[rb].node.strVal
let by = regs[rc].intVal
let v = getOrDefault(g.cacheCounters, destKey)
g.cacheCounters[destKey] = v+by
recordInc(c, c.debug[pc], destKey, by)
of opcNcsAdd:
let g = c.graph
declBC()
let destKey = regs[rb].node.strVal
let val = regs[rc].node
if not contains(g.cacheSeqs, destKey):
g.cacheSeqs[destKey] = newTree(nkStmtList, val)
else:
g.cacheSeqs[destKey].add val
recordAdd(c, c.debug[pc], destKey, val)
of opcNcsIncl:
let g = c.graph
declBC()
let destKey = regs[rb].node.strVal
let val = regs[rc].node
if not contains(g.cacheSeqs, destKey):
g.cacheSeqs[destKey] = newTree(nkStmtList, val)
else:
block search:
for existing in g.cacheSeqs[destKey]:
if exprStructuralEquivalent(existing, val, strictSymEquality=true):
break search
g.cacheSeqs[destKey].add val
recordIncl(c, c.debug[pc], destKey, val)
of opcNcsLen:
let g = c.graph
decodeB(rkInt)
let destKey = regs[rb].node.strVal
regs[ra].intVal =
if contains(g.cacheSeqs, destKey): g.cacheSeqs[destKey].len else: 0
of opcNcsAt:
let g = c.graph
decodeBC(rkNode)
let idx = regs[rc].intVal
let destKey = regs[rb].node.strVal
if contains(g.cacheSeqs, destKey) and idx <% g.cacheSeqs[destKey].len:
regs[ra].node = g.cacheSeqs[destKey][idx.int]
else:
stackTrace(c, tos, pc, formatErrorIndexBound(idx, g.cacheSeqs[destKey].len-1))
of opcNctPut:
let g = c.graph
let destKey = regs[ra].node.strVal
let key = regs[instr.regB].node.strVal
let val = regs[instr.regC].node
if not contains(g.cacheTables, destKey):
g.cacheTables[destKey] = initBTree[string, PNode]()
if not contains(g.cacheTables[destKey], key):
g.cacheTables[destKey].add(key, val)
recordPut(c, c.debug[pc], destKey, key, val)
else:
stackTrace(c, tos, pc, "key already exists: " & key)
of opcNctLen:
let g = c.graph
decodeB(rkInt)
let destKey = regs[rb].node.strVal
regs[ra].intVal =
if contains(g.cacheTables, destKey): g.cacheTables[destKey].len else: 0
of opcNctGet:
let g = c.graph
decodeBC(rkNode)
let destKey = regs[rb].node.strVal
let key = regs[rc].node.strVal
if contains(g.cacheTables, destKey):
if contains(g.cacheTables[destKey], key):
regs[ra].node = getOrDefault(g.cacheTables[destKey], key)
else:
stackTrace(c, tos, pc, "key does not exist: " & key)
else:
stackTrace(c, tos, pc, "key does not exist: " & destKey)
of opcNctHasNext:
let g = c.graph
decodeBC(rkInt)
let destKey = regs[rb].node.strVal
regs[ra].intVal =
if g.cacheTables.contains(destKey):
ord(btrees.hasNext(g.cacheTables[destKey], regs[rc].intVal.int))
else:
0
of opcNctNext:
let g = c.graph
decodeBC(rkNode)
let destKey = regs[rb].node.strVal
let index = regs[rc].intVal
if contains(g.cacheTables, destKey):
let (k, v, nextIndex) = btrees.next(g.cacheTables[destKey], index.int)
regs[ra].node = newTree(nkTupleConstr, newStrNode(k, c.debug[pc]), v,
newIntNode(nkIntLit, nextIndex))
else:
stackTrace(c, tos, pc, "key does not exist: " & destKey)
of opcTypeTrait:
# XXX only supports 'name' for now; we can use regC to encode the
# type trait operation
decodeB(rkNode)
var typ = regs[rb].node.typ
internalAssert c.config, typ != nil
while typ.kind == tyTypeDesc and typ.len > 0: typ = typ[0]
createStr regs[ra]
regs[ra].node.strVal = typ.typeToString(preferExported)
of opcMarshalLoad:
let ra = instr.regA
let rb = instr.regB
inc pc
let typ = c.types[c.code[pc].regBx - wordExcess]
putIntoReg(regs[ra], loadAny(regs[rb].node.strVal, typ, c.cache, c.config, c.idgen))
of opcMarshalStore:
decodeB(rkNode)
inc pc
let typ = c.types[c.code[pc].regBx - wordExcess]
createStrKeepNode(regs[ra])
storeAny(regs[ra].node.strVal, typ, regs[rb].regToNode, c.config)
c.profiler.leave(c)
inc pc
proc execute(c: PCtx, start: int): PNode =
var tos = PStackFrame(prc: nil, comesFrom: 0, next: nil)
newSeq(tos.slots, c.prc.regInfo.len)
result = rawExecute(c, start, tos).regToNode
proc execProc*(c: PCtx; sym: PSym; args: openArray[PNode]): PNode =
c.loopIterations = c.config.maxLoopIterationsVM
if sym.kind in routineKinds:
if sym.typ.len-1 != args.len:
localError(c.config, sym.info,
"NimScript: expected $# arguments, but got $#" % [
$(sym.typ.len-1), $args.len])
else:
let start = genProc(c, sym)
var tos = PStackFrame(prc: sym, comesFrom: 0, next: nil)
let maxSlots = sym.offset
newSeq(tos.slots, maxSlots)
# setup parameters:
if not isEmptyType(sym.typ[0]) or sym.kind == skMacro:
putIntoReg(tos.slots[0], getNullValue(sym.typ[0], sym.info, c.config))
# XXX We could perform some type checking here.
for i in 1..<sym.typ.len:
putIntoReg(tos.slots[i], args[i-1])
result = rawExecute(c, start, tos).regToNode
else:
localError(c.config, sym.info,
"NimScript: attempt to call non-routine: " & sym.name.s)
proc evalStmt*(c: PCtx, n: PNode) =
let n = transformExpr(c.graph, c.idgen, c.module, n)
let start = genStmt(c, n)
# execute new instructions; this redundant opcEof check saves us lots
# of allocations in 'execute':
if c.code[start].opcode != opcEof:
discard execute(c, start)
proc evalExpr*(c: PCtx, n: PNode): PNode =
# deadcode
# `nim --eval:"expr"` might've used it at some point for idetools; could
# be revived for nimsuggest
let n = transformExpr(c.graph, c.idgen, c.module, n)
let start = genExpr(c, n)
assert c.code[start].opcode != opcEof
result = execute(c, start)
proc getGlobalValue*(c: PCtx; s: PSym): PNode =
internalAssert c.config, s.kind in {skLet, skVar} and sfGlobal in s.flags
result = c.globals[s.position-1]
include vmops
proc setupGlobalCtx*(module: PSym; graph: ModuleGraph; idgen: IdGenerator) =
if graph.vm.isNil:
graph.vm = newCtx(module, graph.cache, graph, idgen)
registerAdditionalOps(PCtx graph.vm)
else:
refresh(PCtx graph.vm, module, idgen)
proc myOpen(graph: ModuleGraph; module: PSym; idgen: IdGenerator): PPassContext {.nosinks.} =
#var c = newEvalContext(module, emRepl)
#c.features = {allowCast, allowInfiniteLoops}
#pushStackFrame(c, newStackFrame())
# XXX produce a new 'globals' environment here:
setupGlobalCtx(module, graph, idgen)
result = PCtx graph.vm
proc myProcess(c: PPassContext, n: PNode): PNode =
let c = PCtx(c)
# don't eval errornous code:
if c.oldErrorCount == c.config.errorCounter:
evalStmt(c, n)
result = newNodeI(nkEmpty, n.info)
else:
result = n
c.oldErrorCount = c.config.errorCounter
proc myClose(graph: ModuleGraph; c: PPassContext, n: PNode): PNode =
result = myProcess(c, n)
const evalPass* = makePass(myOpen, myProcess, myClose)
proc evalConstExprAux(module: PSym; idgen: IdGenerator;
g: ModuleGraph; prc: PSym, n: PNode,
mode: TEvalMode): PNode =
#if g.config.errorCounter > 0: return n
let n = transformExpr(g, idgen, module, n)
setupGlobalCtx(module, g, idgen)
var c = PCtx g.vm
let oldMode = c.mode
c.mode = mode
let start = genExpr(c, n, requiresValue = mode!=emStaticStmt)
if c.code[start].opcode == opcEof: return newNodeI(nkEmpty, n.info)
assert c.code[start].opcode != opcEof
when debugEchoCode: c.echoCode start
var tos = PStackFrame(prc: prc, comesFrom: 0, next: nil)
newSeq(tos.slots, c.prc.regInfo.len)
#for i in 0..<c.prc.regInfo.len: tos.slots[i] = newNode(nkEmpty)
result = rawExecute(c, start, tos).regToNode
if result.info.col < 0: result.info = n.info
c.mode = oldMode
proc evalConstExpr*(module: PSym; idgen: IdGenerator; g: ModuleGraph; e: PNode): PNode =
result = evalConstExprAux(module, idgen, g, nil, e, emConst)
proc evalStaticExpr*(module: PSym; idgen: IdGenerator; g: ModuleGraph; e: PNode, prc: PSym): PNode =
result = evalConstExprAux(module, idgen, g, prc, e, emStaticExpr)
proc evalStaticStmt*(module: PSym; idgen: IdGenerator; g: ModuleGraph; e: PNode, prc: PSym) =
discard evalConstExprAux(module, idgen, g, prc, e, emStaticStmt)
proc setupCompileTimeVar*(module: PSym; idgen: IdGenerator; g: ModuleGraph; n: PNode) =
discard evalConstExprAux(module, idgen, g, nil, n, emStaticStmt)
proc prepareVMValue(arg: PNode): PNode =
## strip nkExprColonExpr from tuple values recursively. That is how
## they are expected to be stored in the VM.
# Early abort without copy. No transformation takes place.
if arg.kind in nkLiterals:
return arg
if arg.kind == nkExprColonExpr and arg[0].typ != nil and
arg[0].typ.sym != nil and arg[0].typ.sym.magic == mPNimrodNode:
# Poor mans way of protecting static NimNodes
# XXX: Maybe we need a nkNimNode?
return arg
result = copyNode(arg)
if arg.kind == nkTupleConstr:
for child in arg:
if child.kind == nkExprColonExpr:
result.add prepareVMValue(child[1])
else:
result.add prepareVMValue(child)
else:
for child in arg:
result.add prepareVMValue(child)
proc setupMacroParam(x: PNode, typ: PType): TFullReg =
case typ.kind
of tyStatic:
putIntoReg(result, prepareVMValue(x))
else:
var n = x
if n.kind in {nkHiddenSubConv, nkHiddenStdConv}: n = n[1]
n = n.canonValue
n.flags.incl nfIsRef
n.typ = x.typ
result = TFullReg(kind: rkNode, node: n)
iterator genericParamsInMacroCall*(macroSym: PSym, call: PNode): (PSym, PNode) =
let gp = macroSym.ast[genericParamsPos]
for i in 0..<gp.len:
let genericParam = gp[i].sym
let posInCall = macroSym.typ.len + i
if posInCall < call.len:
yield (genericParam, call[posInCall])
# to prevent endless recursion in macro instantiation
const evalMacroLimit = 1000
#proc errorNode(idgen: IdGenerator; owner: PSym, n: PNode): PNode =
# result = newNodeI(nkEmpty, n.info)
# result.typ = newType(tyError, nextTypeId idgen, owner)
# result.typ.flags.incl tfCheckedForDestructor
proc evalMacroCall*(module: PSym; idgen: IdGenerator; g: ModuleGraph; templInstCounter: ref int;
n, nOrig: PNode, sym: PSym): PNode =
#if g.config.errorCounter > 0: return errorNode(idgen, module, n)
# XXX globalError() is ugly here, but I don't know a better solution for now
inc(g.config.evalMacroCounter)
if g.config.evalMacroCounter > evalMacroLimit:
globalError(g.config, n.info, "macro instantiation too nested")
# immediate macros can bypass any type and arity checking so we check the
# arity here too:
if sym.typ.len > n.safeLen and sym.typ.len > 1:
globalError(g.config, n.info, "in call '$#' got $#, but expected $# argument(s)" % [
n.renderTree, $(n.safeLen-1), $(sym.typ.len-1)])
setupGlobalCtx(module, g, idgen)
var c = PCtx g.vm
let oldMode = c.mode
c.mode = emStaticStmt
c.comesFromHeuristic.line = 0'u16
c.callsite = nOrig
c.templInstCounter = templInstCounter
let start = genProc(c, sym)
var tos = PStackFrame(prc: sym, comesFrom: 0, next: nil)
let maxSlots = sym.offset
newSeq(tos.slots, maxSlots)
# setup arguments:
var L = n.safeLen
if L == 0: L = 1
# This is wrong for tests/reject/tind1.nim where the passed 'else' part
# doesn't end up in the parameter:
#InternalAssert tos.slots.len >= L
# return value:
tos.slots[0] = TFullReg(kind: rkNode, node: newNodeI(nkEmpty, n.info))
# setup parameters:
for i in 1..<sym.typ.len:
tos.slots[i] = setupMacroParam(n[i], sym.typ[i])
let gp = sym.ast[genericParamsPos]
for i in 0..<gp.len:
let idx = sym.typ.len + i
if idx < n.len:
tos.slots[idx] = setupMacroParam(n[idx], gp[i].sym.typ)
else:
dec(g.config.evalMacroCounter)
c.callsite = nil
localError(c.config, n.info, "expected " & $gp.len &
" generic parameter(s)")
# temporary storage:
#for i in L..<maxSlots: tos.slots[i] = newNode(nkEmpty)
result = rawExecute(c, start, tos).regToNode
if result.info.line < 0: result.info = n.info
if cyclicTree(result): globalError(c.config, n.info, "macro produced a cyclic tree")
dec(g.config.evalMacroCounter)
c.callsite = nil
c.mode = oldMode