diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Target/X86/X86ISelLowering.cpp | 38 |
1 files changed, 24 insertions, 14 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index 54e8251d7c3..ec77865e702 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -30103,27 +30103,37 @@ X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI, case X86::FP80_TO_INT64_IN_MEM: { // Change the floating point control register to use "round towards zero" // mode when truncating to an integer value. - int CWFrameIdx = MF->getFrameInfo().CreateStackObject(2, 2, false); + int OrigCWFrameIdx = MF->getFrameInfo().CreateStackObject(2, 2, false); addFrameReference(BuildMI(*BB, MI, DL, - TII->get(X86::FNSTCW16m)), CWFrameIdx); + TII->get(X86::FNSTCW16m)), OrigCWFrameIdx); - // Load the old value of the high byte of the control word... + // Load the old value of the control word... unsigned OldCW = + MF->getRegInfo().createVirtualRegister(&X86::GR32RegClass); + addFrameReference(BuildMI(*BB, MI, DL, TII->get(X86::MOVZX32rm16), OldCW), + OrigCWFrameIdx); + + // OR 0b11 into bit 10 and 11. 0b11 is the encoding for round toward zero. + unsigned NewCW = + MF->getRegInfo().createVirtualRegister(&X86::GR32RegClass); + BuildMI(*BB, MI, DL, TII->get(X86::OR32ri), NewCW) + .addReg(OldCW, RegState::Kill).addImm(0xC00); + + // Extract to 16 bits. + unsigned NewCW16 = MF->getRegInfo().createVirtualRegister(&X86::GR16RegClass); - addFrameReference(BuildMI(*BB, MI, DL, TII->get(X86::MOV16rm), OldCW), - CWFrameIdx); + BuildMI(*BB, MI, DL, TII->get(TargetOpcode::COPY), NewCW16) + .addReg(NewCW, RegState::Kill, X86::sub_16bit); - // Set the high part to be round to zero... - addFrameReference(BuildMI(*BB, MI, DL, TII->get(X86::MOV16mi)), CWFrameIdx) - .addImm(0xC7F); + // Prepare memory for FLDCW. + int NewCWFrameIdx = MF->getFrameInfo().CreateStackObject(2, 2, false); + addFrameReference(BuildMI(*BB, MI, DL, TII->get(X86::MOV16mr)), + NewCWFrameIdx) + .addReg(NewCW16, RegState::Kill); // Reload the modified control word now... addFrameReference(BuildMI(*BB, MI, DL, - TII->get(X86::FLDCW16m)), CWFrameIdx); - - // Restore the memory image of control word to original value - addFrameReference(BuildMI(*BB, MI, DL, TII->get(X86::MOV16mr)), CWFrameIdx) - .addReg(OldCW); + TII->get(X86::FLDCW16m)), NewCWFrameIdx); // Get the X86 opcode to use. unsigned Opc; @@ -30146,7 +30156,7 @@ X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI, // Reload the original control word now. addFrameReference(BuildMI(*BB, MI, DL, - TII->get(X86::FLDCW16m)), CWFrameIdx); + TII->get(X86::FLDCW16m)), OrigCWFrameIdx); MI.eraseFromParent(); // The pseudo instruction is gone now. return BB; |
