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Make comparisons against the null pointer as efficient as integer comparisons
against zero. In particular, don't emit: mov %ESI, 0 cmp %ECX, %ESI instead, emit: test %ECX, %ECX git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13407 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -829,7 +829,14 @@ unsigned ISel::EmitComparison(unsigned OpNum, Value *Op0, Value *Op1,
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unsigned Op0r = getReg(Op0, MBB, IP);
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// Special case handling of: cmp R, i
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if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
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if (isa<ConstantPointerNull>(Op1)) {
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if (OpNum < 2) // seteq/setne -> test
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BuildMI(*MBB, IP, X86::TEST32rr, 2).addReg(Op0r).addReg(Op0r);
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else
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BuildMI(*MBB, IP, X86::CMP32ri, 2).addReg(Op0r).addImm(0);
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return OpNum;
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} else if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
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if (Class == cByte || Class == cShort || Class == cInt) {
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unsigned Op1v = CI->getRawValue();
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@ -829,7 +829,14 @@ unsigned ISel::EmitComparison(unsigned OpNum, Value *Op0, Value *Op1,
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unsigned Op0r = getReg(Op0, MBB, IP);
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// Special case handling of: cmp R, i
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if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
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if (isa<ConstantPointerNull>(Op1)) {
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if (OpNum < 2) // seteq/setne -> test
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BuildMI(*MBB, IP, X86::TEST32rr, 2).addReg(Op0r).addReg(Op0r);
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else
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BuildMI(*MBB, IP, X86::CMP32ri, 2).addReg(Op0r).addImm(0);
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return OpNum;
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} else if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
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if (Class == cByte || Class == cShort || Class == cInt) {
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unsigned Op1v = CI->getRawValue();
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