diff options
Diffstat (limited to 'compiler/vmgen.nim')
| -rw-r--r-- | compiler/vmgen.nim | 88 |
1 files changed, 43 insertions, 45 deletions
diff --git a/compiler/vmgen.nim b/compiler/vmgen.nim index d2243376c..31e04a6c0 100644 --- a/compiler/vmgen.nim +++ b/compiler/vmgen.nim @@ -37,7 +37,9 @@ when hasFFI: import evalffi type - TGenFlag = enum gfAddrOf, gfFieldAccess + TGenFlag = enum + gfNode # Affects how variables are loaded - always loads as rkNode + gfNodeAddr # Affects how variables are loaded - always loads as rkNodeAddr TGenFlags = set[TGenFlag] proc debugInfo(c: PCtx; info: TLineInfo): string = @@ -563,7 +565,7 @@ proc genIndex(c: PCtx; n: PNode; arr: PType): TRegister = proc genAsgnPatch(c: PCtx; le: PNode, value: TRegister) = case le.kind of nkBracketExpr: - let dest = c.genx(le.sons[0], {gfAddrOf, gfFieldAccess}) + let dest = c.genx(le.sons[0], {gfNode}) let idx = c.genIndex(le.sons[1], le.sons[0].typ) c.gABC(le, opcWrArr, dest, idx, value) c.freeTemp(dest) @@ -571,17 +573,17 @@ proc genAsgnPatch(c: PCtx; le: PNode, value: TRegister) = of nkDotExpr, nkCheckedFieldExpr: # XXX field checks here let left = if le.kind == nkDotExpr: le else: le.sons[0] - let dest = c.genx(left.sons[0], {gfAddrOf, gfFieldAccess}) + let dest = c.genx(left.sons[0], {gfNode}) let idx = genField(c, left.sons[1]) c.gABC(left, opcWrObj, dest, idx, value) c.freeTemp(dest) of nkDerefExpr, nkHiddenDeref: - let dest = c.genx(le.sons[0], {gfAddrOf}) + let dest = c.genx(le.sons[0], {gfNode}) c.gABC(le, opcWrDeref, dest, 0, value) c.freeTemp(dest) of nkSym: if le.sym.isGlobal: - let dest = c.genx(le, {gfAddrOf}) + let dest = c.genx(le, {gfNodeAddr}) c.gABC(le, opcWrDeref, dest, 0, value) c.freeTemp(dest) else: @@ -1252,41 +1254,21 @@ proc canElimAddr(n: PNode): PNode = # addr ( deref ( x )) --> x result = n.sons[0].sons[0] -proc genAddrDeref(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode; - flags: TGenFlags) = - # a nop for certain types - let isAddr = opc in {opcAddrNode, opcAddrReg} - if isAddr and (let m = canElimAddr(n); m != nil): +proc genAddr(c: PCtx, n: PNode, dest: var TDest, flags: TGenFlags) = + if (let m = canElimAddr(n); m != nil): gen(c, m, dest, flags) return - let af = if n[0].kind in {nkBracketExpr, nkDotExpr, nkCheckedFieldExpr}: {gfAddrOf, gfFieldAccess} - else: {gfAddrOf} - let newflags = if isAddr: flags+af else: flags - # consider: - # proc foo(f: var ref int) = - # f = new(int) - # proc blah() = - # var x: ref int - # foo x - # - # The type of 'f' is 'var ref int' and of 'x' is 'ref int'. Hence for - # nkAddr we must not use 'unneededIndirection', but for deref we use it. - if not isAddr and unneededIndirection(n.sons[0]): - gen(c, n.sons[0], dest, newflags) - if gfAddrOf notin flags and fitsRegister(n.typ): - c.gABC(n, opcNodeToReg, dest, dest) - elif isAddr and isGlobal(n.sons[0]): + let af = if n[0].kind in {nkBracketExpr, nkDotExpr, nkCheckedFieldExpr}: {gfNode} + else: {gfNodeAddr} + let newflags = flags-{gfNode, gfNodeAddr}+af + + if isGlobal(n.sons[0]): gen(c, n.sons[0], dest, flags+af) else: let tmp = c.genx(n.sons[0], newflags) if dest < 0: dest = c.getTemp(n.typ) - if not isAddr: - gABC(c, n, opc, dest, tmp) - assert n.typ != nil - if gfAddrOf notin flags and fitsRegister(n.typ): - c.gABC(n, opcNodeToReg, dest, dest) - elif c.prc.slots[tmp].kind >= slotTempUnknown: + if c.prc.slots[tmp].kind >= slotTempUnknown: gABC(c, n, opcAddrNode, dest, tmp) # hack ahead; in order to fix bug #1781 we mark the temporary as # permanent, so that it's not used for anything else: @@ -1297,6 +1279,19 @@ proc genAddrDeref(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode; gABC(c, n, opcAddrReg, dest, tmp) c.freeTemp(tmp) +proc genDeref(c: PCtx, n: PNode, dest: var TDest, flags: TGenFlags) = + if unneededIndirection(n.sons[0]): + gen(c, n.sons[0], dest, flags) + if {gfNodeAddr, gfNode} * flags == {} and fitsRegister(n.typ): + c.gABC(n, opcNodeToReg, dest, dest) + else: + let tmp = c.genx(n.sons[0], flags) + if dest < 0: dest = c.getTemp(n.typ) + gABC(c, n, opcLdDeref, dest, tmp) + assert n.typ != nil + if {gfNodeAddr, gfNode} * flags == {} and fitsRegister(n.typ): + c.gABC(n, opcNodeToReg, dest, dest) + proc whichAsgnOpc(n: PNode): TOpcode = case n.typ.skipTypes(abstractRange-{tyTypeDesc}).kind of tyBool, tyChar, tyEnum, tyOrdinal, tyInt..tyInt64, tyUInt..tyUInt64: @@ -1382,7 +1377,7 @@ proc preventFalseAlias(c: PCtx; n: PNode; opc: TOpcode; proc genAsgn(c: PCtx; le, ri: PNode; requiresCopy: bool) = case le.kind of nkBracketExpr: - let dest = c.genx(le.sons[0], {gfAddrOf, gfFieldAccess}) + let dest = c.genx(le.sons[0], {gfNode}) let idx = c.genIndex(le.sons[1], le.sons[0].typ) let tmp = c.genx(ri) if le.sons[0].typ.skipTypes(abstractVarRange-{tyTypeDesc}).kind in { @@ -1394,13 +1389,13 @@ proc genAsgn(c: PCtx; le, ri: PNode; requiresCopy: bool) = of nkDotExpr, nkCheckedFieldExpr: # XXX field checks here let left = if le.kind == nkDotExpr: le else: le.sons[0] - let dest = c.genx(left.sons[0], {gfAddrOf, gfFieldAccess}) + let dest = c.genx(left.sons[0], {gfNode}) let idx = genField(c, left.sons[1]) let tmp = c.genx(ri) c.preventFalseAlias(left, opcWrObj, dest, idx, tmp) c.freeTemp(tmp) of nkDerefExpr, nkHiddenDeref: - let dest = c.genx(le.sons[0], {gfAddrOf}) + let dest = c.genx(le.sons[0], {gfNode}) let tmp = c.genx(ri) c.preventFalseAlias(le, opcWrDeref, dest, 0, tmp) c.freeTemp(tmp) @@ -1409,7 +1404,7 @@ proc genAsgn(c: PCtx; le, ri: PNode; requiresCopy: bool) = checkCanEval(c, le) if s.isGlobal: withTemp(tmp, le.typ): - c.gen(le, tmp, {gfAddrOf}) + c.gen(le, tmp, {gfNodeAddr}) let val = c.genx(ri) c.preventFalseAlias(le, opcWrDeref, tmp, 0, val) c.freeTemp(val) @@ -1427,7 +1422,7 @@ proc genAsgn(c: PCtx; le, ri: PNode; requiresCopy: bool) = else: gen(c, ri, dest) else: - let dest = c.genx(le, {gfAddrOf}) + let dest = c.genx(le, {gfNodeAddr}) genAsgn(c, dest, ri, requiresCopy) proc genTypeLit(c: PCtx; t: PType; dest: var TDest) = @@ -1463,6 +1458,8 @@ proc genGlobalInit(c: PCtx; n: PNode; s: PSym) = c.freeTemp(tmp) proc genRdVar(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags) = + # gfNodeAddr and gfNode are mutually exclusive + assert card(flags * {gfNodeAddr, gfNode}) < 2 let s = n.sym if s.isGlobal: if sfCompileTime in s.flags or c.mode == emRepl: @@ -1474,13 +1471,13 @@ proc genRdVar(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags) = else: genGlobalInit(c, n, s) if dest < 0: dest = c.getTemp(n.typ) assert s.typ != nil - if gfAddrOf notin flags and fitsRegister(s.typ): + if gfNodeAddr in flags: + c.gABx(n, opcLdGlobalAddr, dest, s.position) + elif fitsRegister(s.typ) and gfNode notin flags: var cc = c.getTemp(n.typ) c.gABx(n, opcLdGlobal, cc, s.position) c.gABC(n, opcNodeToReg, dest, cc) c.freeTemp(cc) - elif {gfAddrOf, gfFieldAccess} * flags == {gfAddrOf}: - c.gABx(n, opcLdGlobalAddr, dest, s.position) else: c.gABx(n, opcLdGlobal, dest, s.position) else: @@ -1498,7 +1495,8 @@ proc genRdVar(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags) = cannotEval(c, n) template needsRegLoad(): untyped = - gfAddrOf notin flags and fitsRegister(n.typ.skipTypes({tyVar, tyLent})) + {gfNode, gfNodeAddr} * flags == {} and + fitsRegister(n.typ.skipTypes({tyVar, tyLent})) proc genArrAccess2(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode; flags: TGenFlags) = @@ -1634,7 +1632,7 @@ proc genVarSection(c: PCtx; n: PNode) = c.globals.add(sa) s.position = c.globals.len if a.sons[2].kind != nkEmpty: - let tmp = c.genx(a.sons[0], {gfAddrOf}) + let tmp = c.genx(a.sons[0], {gfNodeAddr}) let val = c.genx(a.sons[2]) c.genAdditionalCopy(a.sons[2], opcWrDeref, tmp, 0, val) c.freeTemp(val) @@ -1839,8 +1837,8 @@ proc gen(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags = {}) = of nkDotExpr: genObjAccess(c, n, dest, flags) of nkCheckedFieldExpr: genCheckedObjAccess(c, n, dest, flags) of nkBracketExpr: genArrAccess(c, n, dest, flags) - of nkDerefExpr, nkHiddenDeref: genAddrDeref(c, n, dest, opcLdDeref, flags) - of nkAddr, nkHiddenAddr: genAddrDeref(c, n, dest, opcAddrNode, flags) + of nkDerefExpr, nkHiddenDeref: genDeref(c, n, dest, flags) + of nkAddr, nkHiddenAddr: genAddr(c, n, dest, flags) of nkIfStmt, nkIfExpr: genIf(c, n, dest) of nkWhenStmt: # This is "when nimvm" node. Chose the first branch. |