[llvm] b1dcd84 - [X86] Copy the nofpexcept flag when folding a load into an instruction using the load folding tables./

[Craig Topper via llvm-commits]

Author: Craig Topper
Date: 2020-01-13T22:02:45-08:00
New Revision: b1dcd84c7ea3c97ddd73f629441be24791f23624

URL: https://github.com/llvm/llvm-project/commit/b1dcd84c7ea3c97ddd73f629441be24791f23624
DIFF: https://github.com/llvm/llvm-project/commit/b1dcd84c7ea3c97ddd73f629441be24791f23624.diff

LOG: [X86] Copy the nofpexcept flag when folding a load into an instruction using the load folding tables./

Added: 
    

Modified: 
    llvm/lib/Target/X86/X86InstrInfo.cpp
    llvm/test/CodeGen/X86/stack-folding-fp-nofpexcept.mir

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/X86/X86InstrInfo.cpp b/llvm/lib/Target/X86/X86InstrInfo.cpp
index f41a27aba3ff..245346d82731 100644
--- a/llvm/lib/Target/X86/X86InstrInfo.cpp
+++ b/llvm/lib/Target/X86/X86InstrInfo.cpp
@@ -4704,6 +4704,10 @@ static MachineInstr *FuseInst(MachineFunction &MF, unsigned Opcode,
 
   updateOperandRegConstraints(MF, *NewMI, TII);
 
+  // Copy the NoFPExcept flag from the instruction we're fusing.
+  if (MI.getFlag(MachineInstr::MIFlag::NoFPExcept))
+    NewMI->setFlag(MachineInstr::MIFlag::NoFPExcept);
+
   MachineBasicBlock *MBB = InsertPt->getParent();
   MBB->insert(InsertPt, NewMI);
 

diff  --git a/llvm/test/CodeGen/X86/stack-folding-fp-nofpexcept.mir b/llvm/test/CodeGen/X86/stack-folding-fp-nofpexcept.mir
index 7a838482d1bb..479c5d45a194 100644
--- a/llvm/test/CodeGen/X86/stack-folding-fp-nofpexcept.mir
+++ b/llvm/test/CodeGen/X86/stack-folding-fp-nofpexcept.mir
@@ -39,8 +39,8 @@ body:             |
     ; CHECK: MOVAPSmr %stack.0, 1, $noreg, 0, $noreg, $xmm1 :: (store 16 into %stack.0)
     ; CHECK: [[COPY:%[0-9]+]]:vr128 = COPY $xmm0
     ; CHECK: INLINEASM &nop, 1, 7405578, def dead %2, 12, implicit-def dead early-clobber $xmm2, 12, implicit-def dead early-clobber $xmm3, 12, implicit-def dead early-clobber $xmm4, 12, implicit-def dead early-clobber $xmm5, 12, implicit-def dead early-clobber $xmm6, 12, implicit-def dead early-clobber $xmm7, 12, implicit-def dead early-clobber $xmm8, 12, implicit-def dead early-clobber $xmm9, 12, implicit-def dead early-clobber $xmm10, 12, implicit-def dead early-clobber $xmm11, 12, implicit-def dead early-clobber $xmm12, 12, implicit-def dead early-clobber $xmm13, 12, implicit-def dead early-clobber $xmm14, 12, implicit-def dead early-clobber $xmm15, 12, implicit-def dead early-clobber $eflags
-    ; CHECK: [[ADDPDrm:%[0-9]+]]:vr128 = ADDPDrm [[ADDPDrm]], %stack.0, 1, $noreg, 0, $noreg, implicit $mxcsr :: (load 16 from %stack.0)
-    ; CHECK: $xmm0 = COPY [[ADDPDrm]]
+    ; CHECK: [[COPY]]:vr128 = nofpexcept ADDPDrm [[COPY]], %stack.0, 1, $noreg, 0, $noreg, implicit $mxcsr :: (load 16 from %stack.0)
+    ; CHECK: $xmm0 = COPY [[COPY]]
     ; CHECK: RET 0, $xmm0
     %1:vr128 = COPY $xmm1
     %3:vr128 = COPY $xmm0