Mapping SDNode flags to MachineInstr flags

Summary: Providing the glue to map SDNode fast math sub flags to MachineInstr fast math sub flags.

Reviewers: spatel, arsenm, wristow

Reviewed By: spatel

Subscribers: wdng

Differential Revision: https://reviews.llvm.org/D46447

llvm-svn: 331567

llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp

@@ -824,9 +824,34 @@ EmitMachineNode(SDNode *Node, bool IsClone, bool IsCloned,
 
   // Add result register values for things that are defined by this
   // instruction.
-  if (NumResults)
+  if (NumResults) {
     CreateVirtualRegisters(Node, MIB, II, IsClone, IsCloned, VRBaseMap);
 
+    // Transfer any IR flags from the SDNode to the MachineInstr
+    MachineInstr *MI = MIB.getInstr();
+    const SDNodeFlags Flags = Node->getFlags();
+    if (Flags.hasNoSignedZeros())
+      MI->setFlag(MachineInstr::MIFlag::FmNsz);
+
+    if (Flags.hasAllowReciprocal())
+      MI->setFlag(MachineInstr::MIFlag::FmArcp);
+
+    if (Flags.hasNoNaNs())
+      MI->setFlag(MachineInstr::MIFlag::FmNoNans);
+
+    if (Flags.hasNoInfs())
+      MI->setFlag(MachineInstr::MIFlag::FmNoInfs);
+
+    if (Flags.hasAllowContract())
+      MI->setFlag(MachineInstr::MIFlag::FmContract);
+
+    if (Flags.hasApproximateFuncs())
+      MI->setFlag(MachineInstr::MIFlag::FmAfn);
+
+    if (Flags.hasAllowReassociation())
+      MI->setFlag(MachineInstr::MIFlag::FmReassoc);
+  }
+
   // Emit all of the actual operands of this instruction, adding them to the
   // instruction as appropriate.
   bool HasOptPRefs = NumDefs > NumResults;

llvm/test/CodeGen/X86/sqrt-fastmath-mir.ll

@@ -7,16 +7,16 @@ define float @foo(float %f) #0 {
 ; CHECK: body:
 ; CHECK:     %0:fr32 = COPY $xmm0
 ; CHECK:     %1:fr32 = VRSQRTSSr killed %2, %0
-; CHECK:     %3:fr32 = VMULSSrr %0, %1
+; CHECK:     %3:fr32 = reassoc VMULSSrr %0, %1
 ; CHECK:     %4:fr32 = VMOVSSrm
 ; CHECK:     %5:fr32 = VFMADD213SSr %1, killed %3, %4
 ; CHECK:     %6:fr32 = VMOVSSrm
-; CHECK:     %7:fr32 = VMULSSrr %1, %6
+; CHECK:     %7:fr32 = reassoc VMULSSrr %1, %6
-; CHECK:     %8:fr32 = VMULSSrr killed %7, killed %5
+; CHECK:     %8:fr32 = reassoc VMULSSrr killed %7, killed %5
-; CHECK:     %9:fr32 = VMULSSrr %0, %8
+; CHECK:     %9:fr32 = reassoc VMULSSrr %0, %8
 ; CHECK:     %10:fr32 = VFMADD213SSr %8, %9, %4
-; CHECK:     %11:fr32 = VMULSSrr %9, %6
+; CHECK:     %11:fr32 = reassoc VMULSSrr %9, %6
-; CHECK:     %12:fr32 = VMULSSrr killed %11, killed %10
+; CHECK:     %12:fr32 = reassoc VMULSSrr killed %11, killed %10
 ; CHECK:     %14:fr32 = FsFLD0SS
 ; CHECK:     %15:fr32 = VCMPSSrr %0, killed %14, 0
 ; CHECK:     %17:vr128 = VANDNPSrr killed %16, killed %13
@@ -31,16 +31,16 @@ define float @rfoo(float %f) #0 {
 ; CHECK: body:             |
 ; CHECK:     %0:fr32 = COPY $xmm0
 ; CHECK:     %1:fr32 = VRSQRTSSr killed %2, %0
-; CHECK:     %3:fr32 = VMULSSrr %0, %1
+; CHECK:     %3:fr32 = nnan ninf nsz arcp contract afn reassoc VMULSSrr %0, %1
 ; CHECK:     %4:fr32 = VMOVSSrm
 ; CHECK:     %5:fr32 = VFMADD213SSr %1, killed %3, %4
 ; CHECK:     %6:fr32 = VMOVSSrm
-; CHECK:     %7:fr32 = VMULSSrr %1, %6
+; CHECK:     %7:fr32 = nnan ninf nsz arcp contract afn reassoc VMULSSrr %1, %6
-; CHECK:     %8:fr32 = VMULSSrr killed %7, killed %5
+; CHECK:     %8:fr32 = nnan ninf nsz arcp contract afn reassoc VMULSSrr killed %7, killed %5
-; CHECK:     %9:fr32 = VMULSSrr %0, %8
+; CHECK:     %9:fr32 = nnan ninf nsz arcp contract afn reassoc VMULSSrr %0, %8
 ; CHECK:     %10:fr32 = VFMADD213SSr %8, killed %9, %4
-; CHECK:     %11:fr32 = VMULSSrr %8, %6
+; CHECK:     %11:fr32 = nnan ninf nsz arcp contract afn reassoc VMULSSrr %8, %6
-; CHECK:     %12:fr32 = VMULSSrr killed %11, killed %10
+; CHECK:     %12:fr32 = nnan ninf nsz arcp contract afn reassoc VMULSSrr killed %11, killed %10
 ; CHECK:     $xmm0 = COPY %12
 ; CHECK:     RET 0, $xmm0
   %sqrt = tail call float @llvm.sqrt.f32(float %f)