diff options
| 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 | 6ac95f967930ad9bad38363f8b79efb67bc1d58c (patch) | |
| tree | 742ee140c4205ebfc79fb8a650da35f7584030bf /lib/Target | |
| parent | 7c8ad7aa41fe65742b071e2172a34db89d417aba (diff) | |
Codegen -1 and -0.0 more efficiently. This implements CodeGen/X86/negatize_zero.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19313 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target')
| -rw-r--r-- | lib/Target/X86/X86ISelSimple.cpp | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/lib/Target/X86/X86ISelSimple.cpp b/lib/Target/X86/X86ISelSimple.cpp index 5e6fd2fbd2..4aeab3e518 100644 --- a/lib/Target/X86/X86ISelSimple.cpp +++ b/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. |