void GenIncDecIndirect(int regDst, int regSrc, int opSz, int tok)
{
int instr = MipsInstrAddU;
if (tok != tokInc)
instr = MipsInstrSubU;
GenReadIndirect(regDst, regSrc, opSz);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
MipsOpConst, 1);
GenWriteIndirect(regSrc, regDst, opSz);
GenExtendRegIfNeeded(regDst, opSz);
}
void GenIncDecLocal(int regDst, int opSz, int ofs, int tok)
{
int instr = MipsInstrAddU;
if (tok != tokInc)
instr = MipsInstrSubU;
GenReadLocal(regDst, opSz, ofs);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
MipsOpConst, 1);
GenWriteLocal(regDst, opSz, ofs);
GenExtendRegIfNeeded(regDst, opSz);
}
STATIC
void GenIncDecIdent(int regDst, int opSz, int label, int tok)
{
int instr = Tr32InstrAdd;
if (tok != tokInc)
instr = Tr32InstrSub;
GenReadIdent(regDst, opSz, label);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
Tr32OpConst, 1);
GenWriteIdent(regDst, opSz, label);
GenExtendRegIfNeeded(regDst, opSz);
}
void GenPostIncDecIdent(int regDst, int opSz, int label, int tok)
{
int instr = MipsInstrAddU;
if (tok != tokPostInc)
instr = MipsInstrSubU;
GenReadIdent(regDst, opSz, label);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
MipsOpConst, 1);
GenWriteIdent(regDst, opSz, label);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
MipsOpConst, -1);
GenExtendRegIfNeeded(regDst, opSz);
}
STATIC
void GenPostIncDecIndirect(int regDst, int regSrc, int opSz, int tok)
{
int instr = Tr32InstrAdd;
if (tok != tokPostInc)
instr = Tr32InstrSub;
GenReadIndirect(regDst, regSrc, opSz);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
Tr32OpConst, 1);
GenWriteIndirect(regSrc, regDst, opSz);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
Tr32OpConst, -1);
GenExtendRegIfNeeded(regDst, opSz);
}
STATIC
void GenPostIncDecLocal(int regDst, int opSz, int ofs, int tok)
{
int instr = Tr32InstrAdd;
if (tok != tokPostInc)
instr = Tr32InstrSub;
GenReadLocal(regDst, opSz, ofs);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
Tr32OpConst, 1);
GenWriteLocal(regDst, opSz, ofs);
GenPrintInstr3Operands(instr, 0,
regDst, 0,
regDst, 0,
Tr32OpConst, -1);
GenExtendRegIfNeeded(regDst, opSz);
}
// Original, primitive stack-based code generator
// DONE: test 32-bit code generation
void GenExpr0(void)
{
int i;
int gotUnary = 0;
int maxCallDepth = 0;
int callDepth = 0;
int paramOfs = 0;
for (i = 0; i < sp; i++)
if (stack[i][0] == '(')
{
if (++callDepth > maxCallDepth)
maxCallDepth = callDepth;
}
else if (stack[i][0] == ')')
{
callDepth--;
}
CanUseTempRegs = maxCallDepth == 0;
TempsUsed = 0;
for (i = 0; i < sp; i++)
{
int tok = stack[i][0];
int v = stack[i][1];
#ifndef NO_ANNOTATIONS
switch (tok)
{
case tokNumInt: printf2(" # %d\n", truncInt(v)); break;
case tokNumUint: printf2(" # %uu\n", truncUint(v)); break;
case tokIdent: printf2(" # %s\n", IdentTable + v); break;
case tokLocalOfs: printf2(" # local ofs\n"); break;
case ')': printf2(" # ) fxn call\n"); break;
case tokUnaryStar: printf2(" # * (read dereference)\n"); break;
case '=': printf2(" # = (write dereference)\n"); break;
case tokShortCirc: printf2(" # short-circuit "); break;
case tokGoto: printf2(" # sh-circ-goto "); break;
case tokLogAnd: printf2(" # short-circuit && target\n"); break;
case tokLogOr: printf2(" # short-circuit || target\n"); break;
case tokIf: case tokIfNot: break;
default: printf2(" # %s\n", GetTokenName(tok)); break;
}
#endif
switch (tok)
{
case tokNumInt:
case tokNumUint:
if (!(i + 1 < sp && (strchr("+-&^|", stack[i + 1][0]) ||
stack[i + 1][0] == tokLShift ||
stack[i + 1][0] == tokRShift ||
stack[i + 1][0] == tokURShift)))
{
if (gotUnary)
GenPushReg(MipsOpRegV0);
GenPrintInstr2Operands(MipsInstrLI, 0,
MipsOpRegV0, 0,
MipsOpConst, v);
}
gotUnary = 1;
break;
case tokIdent:
if (gotUnary)
GenPushReg(MipsOpRegV0);
if (!(i + 1 < sp && (stack[i + 1][0] == ')' ||
stack[i + 1][0] == tokUnaryStar ||
stack[i + 1][0] == tokInc ||
stack[i + 1][0] == tokDec ||
stack[i + 1][0] == tokPostInc ||
stack[i + 1][0] == tokPostDec)))
{
GenPrintInstr2Operands(MipsInstrLA, 0,
MipsOpRegV0, 0,
MipsOpLabel, v);
}
gotUnary = 1;
break;
case tokLocalOfs:
if (gotUnary)
GenPushReg(MipsOpRegV0);
if (!(i + 1 < sp && (stack[i + 1][0] == tokUnaryStar ||
stack[i + 1][0] == tokInc ||
stack[i + 1][0] == tokDec ||
stack[i + 1][0] == tokPostInc ||
stack[i + 1][0] == tokPostDec)))
{
GenPrintInstr3Operands(MipsInstrAddU, 0,
MipsOpRegV0, 0,
MipsOpRegFp, 0,
MipsOpConst, v);
}
gotUnary = 1;
break;
case '(':
if (gotUnary)
GenPushReg(MipsOpRegV0);
gotUnary = 0;
if (v < 16)
GenLocalAlloc(16 - v);
paramOfs = v - 4;
break;
case ',':
if (maxCallDepth == 1)
{
if (paramOfs == 16)
{
GenPushReg(MipsOpRegV0);
gotUnary = 0;
}
if (paramOfs >= 0 && paramOfs <= 12)
{
GenPrintInstr2Operands(MipsInstrMov, 0,
MipsOpRegA0 + paramOfs / 4, 0,
MipsOpRegV0, 0);
gotUnary = 0;
}
paramOfs -= 4;
}
break;
case ')':
if (maxCallDepth != 1)
{
if (v >= 4)
GenPrintInstr2Operands(MipsInstrLW, 0,
MipsOpRegA0, 0,
MipsOpIndRegSp, 0);
if (v >= 8)
GenPrintInstr2Operands(MipsInstrLW, 0,
MipsOpRegA1, 0,
MipsOpIndRegSp, 4);
if (v >= 12)
GenPrintInstr2Operands(MipsInstrLW, 0,
MipsOpRegA2, 0,
MipsOpIndRegSp, 8);
if (v >= 16)
GenPrintInstr2Operands(MipsInstrLW, 0,
MipsOpRegA3, 0,
MipsOpIndRegSp, 12);
}
else
{
int vv = v;
if (vv > 16)
vv = 16;
if (vv)
GenLocalAlloc(vv);
}
if (stack[i - 1][0] == tokIdent)
{
GenPrintInstr1Operand(MipsInstrJAL, 0,
MipsOpLabel, stack[i - 1][1]);
}
else
{
GenPrintInstr1Operand(MipsInstrJAL, 0,
MipsOpRegV0, 0);
}
if (v < 16)
v = 16;
GenLocalAlloc(-v);
break;
case tokUnaryStar:
if (stack[i - 1][0] == tokIdent)
GenReadIdent(MipsOpRegV0, v, stack[i - 1][1]);
else if (stack[i - 1][0] == tokLocalOfs)
GenReadLocal(MipsOpRegV0, v, stack[i - 1][1]);
else
GenReadIndirect(MipsOpRegV0, MipsOpRegV0, v);
break;
case tokUnaryPlus:
break;
case '~':
GenPrintInstr3Operands(MipsInstrNor, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0);
break;
case tokUnaryMinus:
GenPrintInstr3Operands(MipsInstrSubU, 0,
MipsOpRegV0, 0,
MipsOpRegZero, 0,
MipsOpRegV0, 0);
break;
case '+':
case '-':
case '*':
case '&':
case '^':
case '|':
case tokLShift:
case tokRShift:
case tokURShift:
if ((stack[i - 1][0] == tokNumInt || stack[i - 1][0] == tokNumUint) && tok != '*')
{
int instr = GenGetBinaryOperatorInstr(tok);
GenPrintInstr3Operands(instr, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, stack[i - 1][1]);
}
else
{
int instr = GenGetBinaryOperatorInstr(tok);
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(instr, 0,
MipsOpRegV0, 0,
reg, 0,
MipsOpRegV0, 0);
}
break;
case '/':
case tokUDiv:
case '%':
case tokUMod:
{
int reg = GenPopReg(MipsOpRegT0);
if (tok == '/' || tok == '%')
GenPrintInstr2Operands(MipsInstrDiv, 0,
reg, 0,
MipsOpRegV0, 0);
else
GenPrintInstr2Operands(MipsInstrDivU, 0,
reg, 0,
MipsOpRegV0, 0);
if (tok == '%' || tok == tokUMod)
GenPrintInstr1Operand(MipsInstrMfHi, 0,
MipsOpRegV0, 0);
else
GenPrintInstr1Operand(MipsInstrMfLo, 0,
MipsOpRegV0, 0);
}
break;
case tokInc:
case tokDec:
if (stack[i - 1][0] == tokIdent)
{
GenIncDecIdent(MipsOpRegV0, v, stack[i - 1][1], tok);
}
else if (stack[i - 1][0] == tokLocalOfs)
{
GenIncDecLocal(MipsOpRegV0, v, stack[i - 1][1], tok);
}
else
{
GenPrintInstr2Operands(MipsInstrMov, 0,
MipsOpRegT0, 0,
MipsOpRegV0, 0);
GenIncDecIndirect(MipsOpRegV0, MipsOpRegT0, v, tok);
}
break;
case tokPostInc:
case tokPostDec:
if (stack[i - 1][0] == tokIdent)
{
GenPostIncDecIdent(MipsOpRegV0, v, stack[i - 1][1], tok);
}
else if (stack[i - 1][0] == tokLocalOfs)
{
GenPostIncDecLocal(MipsOpRegV0, v, stack[i - 1][1], tok);
}
else
{
GenPrintInstr2Operands(MipsInstrMov, 0,
MipsOpRegT0, 0,
MipsOpRegV0, 0);
GenPostIncDecIndirect(MipsOpRegV0, MipsOpRegT0, v, tok);
}
break;
case tokPostAdd:
case tokPostSub:
{
int instr = GenGetBinaryOperatorInstr(tok);
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr2Operands(MipsInstrMov, 0,
MipsOpRegT1, 0,
MipsOpRegV0, 0);
GenReadIndirect(MipsOpRegV0, reg, v);
GenPrintInstr3Operands(instr, 0,
MipsOpRegT1, 0,
MipsOpRegT1, 0,
MipsOpRegV0, 0);
GenWriteIndirect(reg, MipsOpRegT1, v);
}
break;
case tokAssignAdd:
case tokAssignSub:
case tokAssignMul:
case tokAssignAnd:
case tokAssignXor:
case tokAssignOr:
case tokAssignLSh:
case tokAssignRSh:
case tokAssignURSh:
{
int instr = GenGetBinaryOperatorInstr(tok);
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr2Operands(MipsInstrMov, 0,
MipsOpRegT1, 0,
MipsOpRegV0, 0);
GenReadIndirect(MipsOpRegV0, reg, v);
GenPrintInstr3Operands(instr, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpRegT1, 0);
GenWriteIndirect(reg, MipsOpRegV0, v);
GenExtendRegIfNeeded(MipsOpRegV0, v);
}
break;
case tokAssignDiv:
case tokAssignUDiv:
case tokAssignMod:
case tokAssignUMod:
{
int reg = GenPopReg(MipsOpRegT0);
GenReadIndirect(MipsOpRegT1, reg, v);
if (tok == tokAssignDiv || tok == tokAssignMod)
GenPrintInstr2Operands(MipsInstrDiv, 0,
MipsOpRegT1, 0,
MipsOpRegV0, 0);
else
GenPrintInstr2Operands(MipsInstrDivU, 0,
MipsOpRegT1, 0,
MipsOpRegV0, 0);
if (tok == tokAssignMod || tok == tokAssignUMod)
GenPrintInstr1Operand(MipsInstrMfHi, 0,
MipsOpRegV0, 0);
else
GenPrintInstr1Operand(MipsInstrMfLo, 0,
MipsOpRegV0, 0);
GenWriteIndirect(reg, MipsOpRegV0, v);
GenExtendRegIfNeeded(MipsOpRegV0, v);
}
break;
case '=':
{
int reg = GenPopReg(MipsOpRegT0);
GenWriteIndirect(reg, MipsOpRegV0, v);
GenExtendRegIfNeeded(MipsOpRegV0, v);
}
break;
/*
i = il < ir; // i = slt(il, ir);
i = il <= ir; // i = slt(ir, il) ^ 1;
i = il > ir; // i = slt(ir, il);
i = il >= ir; // i = slt(il, ir) ^ 1;
i = il == ir; // i = sltu(il ^ ir, 1);
i = il != ir; // i = sltu(0, il ^ ir);
*/
case '<':
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrSLT, 0,
MipsOpRegV0, 0,
reg, 0,
MipsOpRegV0, 0);
}
break;
case tokULess:
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrSLTU, 0,
MipsOpRegV0, 0,
reg, 0,
MipsOpRegV0, 0);
}
break;
case '>':
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrSLT, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
reg, 0);
}
break;
case tokUGreater:
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrSLTU, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
reg, 0);
}
break;
case tokLEQ:
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrSLT, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
reg, 0);
GenPrintInstr3Operands(MipsInstrXor, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 1);
}
break;
case tokULEQ:
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrSLTU, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
reg, 0);
GenPrintInstr3Operands(MipsInstrXor, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 1);
}
break;
case tokGEQ:
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrSLT, 0,
MipsOpRegV0, 0,
reg, 0,
MipsOpRegV0, 0);
GenPrintInstr3Operands(MipsInstrXor, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 1);
}
break;
case tokUGEQ:
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrSLTU, 0,
MipsOpRegV0, 0,
reg, 0,
MipsOpRegV0, 0);
GenPrintInstr3Operands(MipsInstrXor, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 1);
}
break;
case tokEQ:
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrXor, 0,
MipsOpRegV0, 0,
reg, 0,
MipsOpRegV0, 0);
GenPrintInstr3Operands(MipsInstrSLTU, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 1);
}
break;
case tokNEQ:
{
int reg = GenPopReg(MipsOpRegT0);
GenPrintInstr3Operands(MipsInstrXor, 0,
MipsOpRegV0, 0,
reg, 0,
MipsOpRegV0, 0);
GenPrintInstr3Operands(MipsInstrSLTU, 0,
MipsOpRegV0, 0,
MipsOpRegZero, 0,
MipsOpRegV0, 0);
}
break;
case tok_Bool:
GenPrintInstr3Operands(MipsInstrSLTU, 0,
MipsOpRegV0, 0,
MipsOpRegZero, 0,
MipsOpRegV0, 0);
break;
case tokSChar:
GenPrintInstr3Operands(MipsInstrSLL, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 24);
GenPrintInstr3Operands(MipsInstrSRA, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 24);
break;
case tokUChar:
GenPrintInstr3Operands(MipsInstrAnd, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 0xFF);
break;
case tokShort:
GenPrintInstr3Operands(MipsInstrSLL, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 16);
GenPrintInstr3Operands(MipsInstrSRA, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 16);
break;
case tokUShort:
GenPrintInstr3Operands(MipsInstrAnd, 0,
MipsOpRegV0, 0,
MipsOpRegV0, 0,
MipsOpConst, 0xFFFF);
break;
case tokShortCirc:
#ifndef NO_ANNOTATIONS
if (v >= 0)
printf2("&&\n");
else
printf2("||\n");
#endif
if (v >= 0)
GenJumpIfZero(v); // &&
else
GenJumpIfNotZero(-v); // ||
gotUnary = 0;
break;
case tokGoto:
#ifndef NO_ANNOTATIONS
printf2("goto\n");
#endif
GenJumpUncond(v);
gotUnary = 0;
break;
case tokLogAnd:
case tokLogOr:
GenNumLabel(v);
break;
case tokVoid:
gotUnary = 0;
break;
case tokComma:
break;
case tokIf:
GenJumpIfNotZero(stack[i][1]);
break;
case tokIfNot:
GenJumpIfZero(stack[i][1]);
break;
default:
//error("Error: Internal Error: GenExpr0(): unexpected token %s\n", GetTokenName(tok));
errorInternal(102);
break;
}
}
}