[FPEnv] Add fptosi and fptoui constrained intrinsics.

This implements constrained floating point intrinsics for FP to signed and
unsigned integers.

Quoting from D32319:
The purpose of the constrained intrinsics is to force the optimizer to
respect the restrictions that will be necessary to support things like the
STDC FENV_ACCESS ON pragma without interfering with optimizations when
these restrictions are not needed.

Reviewed by:	Andrew Kaylor, Craig Topper, Hal Finkel, Cameron McInally, Roman Lebedev, Kit Barton
Approved by:	Craig Topper
Differential Revision:	http://reviews.llvm.org/D63782

llvm-svn: 370228

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index cf43869..105fb42 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -6106,6 +6106,8 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
   case Intrinsic::experimental_constrained_fdiv:
   case Intrinsic::experimental_constrained_frem:
   case Intrinsic::experimental_constrained_fma:
+  case Intrinsic::experimental_constrained_fptosi:
+  case Intrinsic::experimental_constrained_fptoui:
   case Intrinsic::experimental_constrained_fptrunc:
   case Intrinsic::experimental_constrained_fpext:
   case Intrinsic::experimental_constrained_sqrt:
@@ -6899,6 +6901,12 @@ void SelectionDAGBuilder::visitConstrainedFPIntrinsic(
   case Intrinsic::experimental_constrained_fma:
     Opcode = ISD::STRICT_FMA;
     break;
+  case Intrinsic::experimental_constrained_fptosi:
+    Opcode = ISD::STRICT_FP_TO_SINT;
+    break;
+  case Intrinsic::experimental_constrained_fptoui:
+    Opcode = ISD::STRICT_FP_TO_UINT;
+    break;
   case Intrinsic::experimental_constrained_fptrunc:
     Opcode = ISD::STRICT_FP_ROUND;
     break;