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| author | Chris Lattner <sabre@nondot.org> | 2005-01-06 21:19:16 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2005-01-06 21:19:16 +0000 |
| commit | ae154820769f81e8b1071779d58aa72a3b03614b (patch) | |
| tree | c6198e17b10c631e479a7bd498e3d1b744c06f15 /llvm/lib | |
| parent | 9eef99ef433f26f675f7745ee4cb801a292489be (diff) | |
| download | bcm5719-llvm-ae154820769f81e8b1071779d58aa72a3b03614b.tar.gz bcm5719-llvm-ae154820769f81e8b1071779d58aa72a3b03614b.zip | |
Codegen -1 and -0.0 more efficiently. This implements CodeGen/X86/negatize_zero.ll
llvm-svn: 19313
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Target/X86/X86ISelSimple.cpp | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/llvm/lib/Target/X86/X86ISelSimple.cpp b/llvm/lib/Target/X86/X86ISelSimple.cpp index 5e6fd2fbd2d..4aeab3e5184 100644 --- a/llvm/lib/Target/X86/X86ISelSimple.cpp +++ b/llvm/lib/Target/X86/X86ISelSimple.cpp @@ -560,8 +560,15 @@ void X86ISel::copyConstantToRegister(MachineBasicBlock *MBB, BuildMI(*MBB, IP, X86::FLD0, 0, R); else if (CFP->isExactlyValue(+1.0)) BuildMI(*MBB, IP, X86::FLD1, 0, R); - else { // FIXME: PI, other native values - // FIXME: Could handle -1.0 with FLD1/FCHS + else if (CFP->isExactlyValue(-0.0)) { + unsigned Tmp = makeAnotherReg(Type::DoubleTy); + BuildMI(*MBB, IP, X86::FLD0, 0, Tmp); + BuildMI(*MBB, IP, X86::FCHS, 1, R).addReg(Tmp); + } else if (CFP->isExactlyValue(-1.0)) { + unsigned Tmp = makeAnotherReg(Type::DoubleTy); + BuildMI(*MBB, IP, X86::FLD1, 0, Tmp); + BuildMI(*MBB, IP, X86::FCHS, 1, R).addReg(Tmp); + } else { // FIXME: PI, other native values // FIXME: 2*PI -> LDPI + FADD // Otherwise we need to spill the constant to memory. |
