6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-09-28 22:55:52 +00:00
Code Issues Projects Releases Wiki Activity

Codegen -1 and -0.0 more efficiently. This implements CodeGen/X86/negatize_zero.ll

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19313 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2005-01-06 21:19:16 +00:00
parent 7c8ad7aa41
commit 6ac95f9679
1 changed files with 9 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
lib/Target/X86/X86ISelSimple.cpp
View File

@ -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.