[X86] Custom promote i32->f80 uint_to_fp on AVX512 64-bit targets.

Reuse the same code to promote all i32 uint_to_fp on 64-bit targets
to simplify the X86ISelLowering constructor.

llvm-svn: 370693

1 files changed, 7 insertions, 8 deletions

diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index f29d50fccb2..6f0fb3ac97b 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -221,14 +221,7 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
   setOperationAction(ISD::UINT_TO_FP       , MVT::i8   , Promote);
   setOperationAction(ISD::UINT_TO_FP       , MVT::i16  , Promote);
 
-  if (Subtarget.is64Bit()) {
-    if (!Subtarget.useSoftFloat() && Subtarget.hasAVX512())
-      // f32/f64 are legal, f80 is custom.
-      setOperationAction(ISD::UINT_TO_FP   , MVT::i32  , Custom);
-    else
-      setOperationAction(ISD::UINT_TO_FP   , MVT::i32  , Promote);
-    setOperationAction(ISD::UINT_TO_FP     , MVT::i64  , Custom);
-  } else if (!Subtarget.useSoftFloat()) {
+  if (!Subtarget.useSoftFloat()) {
     // We have an algorithm for SSE2->double, and we turn this into a
     // 64-bit FILD followed by conditional FADD for other targets.
     setOperationAction(ISD::UINT_TO_FP     , MVT::i64  , Custom);
@@ -18657,6 +18650,12 @@ SDValue X86TargetLowering::LowerUINT_TO_FP(SDValue Op,
     return Op;
   }
 
+  // Promote i32 to i64 and use a signed conversion on 64-bit targets.
+  if (SrcVT == MVT::i32 && Subtarget.is64Bit()) {
+    N0 = DAG.getNode(ISD::ZERO_EXTEND, dl, MVT::i64, N0);
+    return DAG.getNode(ISD::SINT_TO_FP, dl, DstVT, N0);
+  }
+
   if (SDValue V = LowerI64IntToFP_AVX512DQ(Op, DAG, Subtarget))
     return V;