diff options
Diffstat (limited to 'compiler/vm.nim')
| -rw-r--r-- | compiler/vm.nim | 92 |
1 files changed, 76 insertions, 16 deletions
diff --git a/compiler/vm.nim b/compiler/vm.nim index 0d5386502..fb8749250 100644 --- a/compiler/vm.nim +++ b/compiler/vm.nim @@ -48,9 +48,17 @@ type # XXX 'break' should perform cleanup actions # What does the C backend do for it? -proc stackTraceAux(c: PCtx; x: PStackFrame; pc: int) = +proc stackTraceAux(c: PCtx; x: PStackFrame; pc: int; recursionLimit=100) = if x != nil: - stackTraceAux(c, x.next, x.comesFrom) + if recursionLimit == 0: + var calls = 0 + var x = x + while x != nil: + inc calls + x = x.next + msgWriteln($calls & " calls omitted\n") + return + stackTraceAux(c, x.next, x.comesFrom, recursionLimit-1) var info = c.debug[pc] # we now use the same format as in system/except.nim var s = toFilename(info) @@ -222,13 +230,14 @@ proc pushSafePoint(f: PStackFrame; pc: int) = proc popSafePoint(f: PStackFrame) = discard f.safePoints.pop() -proc cleanUpOnException(c: PCtx; tos: PStackFrame; regs: seq[TFullReg]): int = +proc cleanUpOnException(c: PCtx; tos: PStackFrame): + tuple[pc: int, f: PStackFrame] = let raisedType = c.currentExceptionA.typ.skipTypes(abstractPtrs) var f = tos while true: while f.safePoints.isNil or f.safePoints.len == 0: f = f.next - if f.isNil: return -1 + if f.isNil: return (-1, nil) var pc2 = f.safePoints[f.safePoints.high] var nextExceptOrFinally = -1 @@ -244,13 +253,13 @@ proc cleanUpOnException(c: PCtx; tos: PStackFrame; regs: seq[TFullReg]): int = c.currentExceptionB = c.currentExceptionA c.currentExceptionA = nil # execute the corresponding handler: - return pc2 + return (pc2, f) inc pc2 if nextExceptOrFinally >= 0: pc2 = nextExceptOrFinally if c.code[pc2].opcode == opcFinally: # execute the corresponding handler, but don't quit walking the stack: - return pc2 + return (pc2, f) # not the right one: discard f.safePoints.pop @@ -495,18 +504,46 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg = else: stackTrace(c, tos, pc, errNilAccess) of opcAddInt: decodeBC(rkInt) - regs[ra].intVal = regs[rb].intVal + regs[rc].intVal + 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.debug[pc], warnUser, "came here") #debug regs[rb].node - regs[ra].intVal = regs[rb].intVal + imm + 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) - regs[ra].intVal = regs[rb].intVal - regs[rc].intVal + 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) - regs[ra].intVal = regs[rb].intVal - imm + 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 @@ -539,7 +576,18 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg = regs[ra].intVal = nimsets.cardSet(regs[rb].node) of opcMulInt: decodeBC(rkInt) - regs[ra].intVal = regs[rb].intVal * regs[rc].intVal + 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) @@ -632,7 +680,11 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg = of opcUnaryMinusInt: decodeB(rkInt) assert regs[rb].kind == rkInt - regs[ra].intVal = -regs[rb].intVal + 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 @@ -826,19 +878,27 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg = of opcFinallyEnd: if c.currentExceptionA != nil: # we are in a cleanup run: - pc = cleanUpOnException(c, tos, regs)-1 - if pc < 0: + let (newPc, newTos) = cleanUpOnException(c, tos) + if newPc-1 < 0: bailOut(c, tos) return + pc = newPc-1 + if tos != newTos: + tos = newTos + move(regs, tos.slots) of opcRaise: let raised = regs[ra].node c.currentExceptionA = raised c.exceptionInstr = pc + let (newPc, newTos) = cleanUpOnException(c, tos) # -1 because of the following 'inc' - pc = cleanUpOnException(c, tos, regs) - 1 - if pc < 0: + if pc-1 < 0: bailOut(c, tos) return + pc = newPc -1 + if tos != newTos: + tos = newTos + move(regs, tos.slots) of opcNew: ensureKind(rkNode) let typ = c.types[instr.regBx - wordExcess] |