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

1 files changed, 26 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp b/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
index dd28f6f561b..0027982bbea 100644
--- a/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
+++ b/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;