InstSelectSimple.cpp: Give promote32 a comment. Add initial

implementation of getReg() for arguments.

MachineCodeEmitter.cpp: Fix using EBP with index, scale and no
 displacement (whew!) due to Chris.

Printer.cpp: Fix printing out index and scale in memory references.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4998 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Brian Gaeke
2002-12-13 07:56:18 +00:00
parent 3153b35a52
commit 95780cccef
6 changed files with 58 additions and 16 deletions

View File

@@ -114,9 +114,10 @@ namespace {
abort();
}
void promote32(unsigned targetReg, Value *V);
/// promote32 - Make a value 32-bits wide, and put it somewhere.
void promote32 (const unsigned targetReg, Value *v);
// emitGEPOperation - Common code shared between visitGetElemenPtrInst and
// emitGEPOperation - Common code shared between visitGetElementPtrInst and
// constant expression GEP support.
//
void emitGEPOperation(Value *Src, User::op_iterator IdxBegin,
@@ -156,7 +157,25 @@ namespace {
// Move the address of the global into the register
BuildMI(BB, X86::MOVir32, 1, Reg).addReg(GV);
} else if (Argument *A = dyn_cast<Argument>(V)) {
std::cerr << "ERROR: Arguments not implemented in SimpleInstSel\n";
// Find the position of the argument in the argument list.
const Function *f = F->getFunction ();
int counter = 0, argPosition = -1;
for (Function::const_aiterator ai = f->abegin (), ae = f->aend ();
ai != ae; ++ai) {
++counter;
if (&(*ai) == A) {
argPosition = counter;
}
}
assert (argPosition != -1
&& "Argument not found in current function's argument list");
// Load it out of the stack frame at EBP + 4*argPosition.
// (First, load Reg with argPosition, then load Reg with DWORD
// PTR [EBP + 4*Reg].)
BuildMI (BB, X86::MOVir32, 1, Reg).addZImm (argPosition);
BuildMI (BB, X86::MOVmr32, 4,
Reg).addReg (X86::EBP).addZImm (4).addReg (Reg).addSImm (0);
// std::cerr << "ERROR: Arguments not implemented in SimpleInstSel\n";
}
return Reg;

View File

@@ -157,17 +157,19 @@ void Emitter::emitMemModRMByte(const MachineInstr &MI,
assert(IndexReg.getReg() != X86::ESP && "Cannot use ESP as index reg!");
bool ForceDisp32 = false;
bool ForceDisp8 = false;
if (BaseReg.getReg() == 0) {
// If there is no base register, we emit the special case SIB byte with
// MOD=0, BASE=5, to JUST get the index, scale, and displacement.
MCE.emitByte(ModRMByte(0, RegOpcodeField, 4));
ForceDisp32 = true;
} else if (Disp.getImmedValue() == 0) {
} else if (Disp.getImmedValue() == 0 && BaseReg.getReg() != X86::EBP) {
// Emit no displacement ModR/M byte
MCE.emitByte(ModRMByte(0, RegOpcodeField, 4));
} else if (isDisp8(Disp.getImmedValue())) {
// Emit the disp8 encoding...
MCE.emitByte(ModRMByte(1, RegOpcodeField, 4));
ForceDisp8 = true; // Make sure to force 8 bit disp if Base=EBP
} else {
// Emit the normal disp32 encoding...
MCE.emitByte(ModRMByte(2, RegOpcodeField, 4));
@@ -189,7 +191,7 @@ void Emitter::emitMemModRMByte(const MachineInstr &MI,
}
// Do we need to output a displacement?
if (Disp.getImmedValue() != 0 || ForceDisp32) {
if (Disp.getImmedValue() != 0 || ForceDisp32 || ForceDisp8) {
if (!ForceDisp32 && isDisp8(Disp.getImmedValue()))
emitConstant(Disp.getImmedValue(), 1);
else

View File

@@ -148,8 +148,8 @@ static void printMemReference(std::ostream &O, const MachineInstr *MI,
if (IndexReg.getReg()) {
if (NeedPlus) O << " + ";
if (IndexReg.getImmedValue() != 1)
O << IndexReg.getImmedValue() << "*";
if (Scale.getImmedValue() != 1)
O << Scale.getImmedValue() << "*";
printOp(O, IndexReg, RI);
NeedPlus = true;
}

View File

@@ -148,8 +148,8 @@ static void printMemReference(std::ostream &O, const MachineInstr *MI,
if (IndexReg.getReg()) {
if (NeedPlus) O << " + ";
if (IndexReg.getImmedValue() != 1)
O << IndexReg.getImmedValue() << "*";
if (Scale.getImmedValue() != 1)
O << Scale.getImmedValue() << "*";
printOp(O, IndexReg, RI);
NeedPlus = true;
}

View File

@@ -157,17 +157,19 @@ void Emitter::emitMemModRMByte(const MachineInstr &MI,
assert(IndexReg.getReg() != X86::ESP && "Cannot use ESP as index reg!");
bool ForceDisp32 = false;
bool ForceDisp8 = false;
if (BaseReg.getReg() == 0) {
// If there is no base register, we emit the special case SIB byte with
// MOD=0, BASE=5, to JUST get the index, scale, and displacement.
MCE.emitByte(ModRMByte(0, RegOpcodeField, 4));
ForceDisp32 = true;
} else if (Disp.getImmedValue() == 0) {
} else if (Disp.getImmedValue() == 0 && BaseReg.getReg() != X86::EBP) {
// Emit no displacement ModR/M byte
MCE.emitByte(ModRMByte(0, RegOpcodeField, 4));
} else if (isDisp8(Disp.getImmedValue())) {
// Emit the disp8 encoding...
MCE.emitByte(ModRMByte(1, RegOpcodeField, 4));
ForceDisp8 = true; // Make sure to force 8 bit disp if Base=EBP
} else {
// Emit the normal disp32 encoding...
MCE.emitByte(ModRMByte(2, RegOpcodeField, 4));
@@ -189,7 +191,7 @@ void Emitter::emitMemModRMByte(const MachineInstr &MI,
}
// Do we need to output a displacement?
if (Disp.getImmedValue() != 0 || ForceDisp32) {
if (Disp.getImmedValue() != 0 || ForceDisp32 || ForceDisp8) {
if (!ForceDisp32 && isDisp8(Disp.getImmedValue()))
emitConstant(Disp.getImmedValue(), 1);
else

View File

@@ -114,9 +114,10 @@ namespace {
abort();
}
void promote32(unsigned targetReg, Value *V);
/// promote32 - Make a value 32-bits wide, and put it somewhere.
void promote32 (const unsigned targetReg, Value *v);
// emitGEPOperation - Common code shared between visitGetElemenPtrInst and
// emitGEPOperation - Common code shared between visitGetElementPtrInst and
// constant expression GEP support.
//
void emitGEPOperation(Value *Src, User::op_iterator IdxBegin,
@@ -156,7 +157,25 @@ namespace {
// Move the address of the global into the register
BuildMI(BB, X86::MOVir32, 1, Reg).addReg(GV);
} else if (Argument *A = dyn_cast<Argument>(V)) {
std::cerr << "ERROR: Arguments not implemented in SimpleInstSel\n";
// Find the position of the argument in the argument list.
const Function *f = F->getFunction ();
int counter = 0, argPosition = -1;
for (Function::const_aiterator ai = f->abegin (), ae = f->aend ();
ai != ae; ++ai) {
++counter;
if (&(*ai) == A) {
argPosition = counter;
}
}
assert (argPosition != -1
&& "Argument not found in current function's argument list");
// Load it out of the stack frame at EBP + 4*argPosition.
// (First, load Reg with argPosition, then load Reg with DWORD
// PTR [EBP + 4*Reg].)
BuildMI (BB, X86::MOVir32, 1, Reg).addZImm (argPosition);
BuildMI (BB, X86::MOVmr32, 4,
Reg).addReg (X86::EBP).addZImm (4).addReg (Reg).addSImm (0);
// std::cerr << "ERROR: Arguments not implemented in SimpleInstSel\n";
}
return Reg;