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| author | Evan Cheng <evan.cheng@apple.com> | 2006-09-13 19:07:28 +0000 |
|---|---|---|
| committer | Evan Cheng <evan.cheng@apple.com> | 2006-09-13 19:07:28 +0000 |
| commit | 80543c83057622884d86dd8758a6d560c41e9a8b (patch) | |
| tree | 53bd6da0420dc70b3481e67eb85d9f50b7efc024 /lib/Target/X86/X86CodeEmitter.cpp | |
| parent | cf2112a0a014e834d720a86824828b47ccd1a48b (diff) | |
| download | external_llvm-80543c83057622884d86dd8758a6d560c41e9a8b.tar.gz external_llvm-80543c83057622884d86dd8758a6d560c41e9a8b.tar.bz2 external_llvm-80543c83057622884d86dd8758a6d560c41e9a8b.zip | |
Skip over first operand when determining REX prefix for two-address code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30300 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/X86/X86CodeEmitter.cpp')
| -rw-r--r-- | lib/Target/X86/X86CodeEmitter.cpp | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp index 0ac8bc5f32..8d1e91285e 100644 --- a/lib/Target/X86/X86CodeEmitter.cpp +++ b/lib/Target/X86/X86CodeEmitter.cpp @@ -470,9 +470,12 @@ unsigned Emitter::determineREX(const MachineInstr &MI) { REX |= 1 << 3; if (MI.getNumOperands()) { + bool isTwoAddr = (Desc.Flags & M_2_ADDR_FLAG) != 0; + // If it accesses SPL, BPL, SIL, or DIL, then it requires a 0x40 REX prefix. bool isTrunc8 = isX86_64TruncToByte(Opcode); - for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) { + unsigned i = isTwoAddr ? 1 : 0; + for (unsigned e = MI.getNumOperands(); i != e; ++i) { const MachineOperand& MO = MI.getOperand(i); if (MO.isRegister()) { unsigned Reg = MO.getReg(); @@ -493,7 +496,8 @@ unsigned Emitter::determineREX(const MachineInstr &MI) { case X86II::MRMSrcReg: { if (isX86_64ExtendedReg(MI.getOperand(0))) REX |= 1 << 2; - for (unsigned i = 1, e = MI.getNumOperands(); i != e; ++i) { + i = isTwoAddr ? 2 : 1; + for (unsigned e = MI.getNumOperands(); i != e; ++i) { const MachineOperand& MO = MI.getOperand(i); if (isX86_64ExtendedReg(MO)) REX |= 1 << 0; @@ -504,7 +508,8 @@ unsigned Emitter::determineREX(const MachineInstr &MI) { if (isX86_64ExtendedReg(MI.getOperand(0))) REX |= 1 << 2; unsigned Bit = 0; - for (unsigned i = 1; i != 5; ++i) { + i = isTwoAddr ? 2 : 1; + for (; i != MI.getNumOperands(); ++i) { const MachineOperand& MO = MI.getOperand(i); if (MO.isRegister()) { if (isX86_64ExtendedReg(MO)) @@ -519,11 +524,12 @@ unsigned Emitter::determineREX(const MachineInstr &MI) { case X86II::MRM4m: case X86II::MRM5m: case X86II::MRM6m: case X86II::MRM7m: case X86II::MRMDestMem: { - if (MI.getNumOperands() >= 5 && - isX86_64ExtendedReg(MI.getOperand(4))) + unsigned e = isTwoAddr ? 5 : 4; + i = isTwoAddr ? 1 : 0; + if (MI.getNumOperands() > e && isX86_64ExtendedReg(MI.getOperand(e))) REX |= 1 << 2; unsigned Bit = 0; - for (unsigned i = 0; i != 4; ++i) { + for (; i != e; ++i) { const MachineOperand& MO = MI.getOperand(i); if (MO.isRegister()) { if (isX86_64ExtendedReg(MO)) @@ -536,7 +542,8 @@ unsigned Emitter::determineREX(const MachineInstr &MI) { default: { if (isX86_64ExtendedReg(MI.getOperand(0))) REX |= 1 << 0; - for (unsigned i = 1, e = MI.getNumOperands(); i != e; ++i) { + i = isTwoAddr ? 2 : 1; + for (unsigned e = MI.getNumOperands(); i != e; ++i) { const MachineOperand& MO = MI.getOperand(i); if (isX86_64ExtendedReg(MO)) REX |= 1 << 2; |