[X86][FastISel] X86SelectIntToFP - don't assume value type is simple.

Fixes #68068

Author: RKSimon

llvm/lib/Target/X86/X86FastISel.cpp

@@ -2391,7 +2391,7 @@ bool X86FastISel::X86SelectIntToFP(const Instruction *I, bool IsSigned) {
     return false;
 
   // TODO: We could sign extend narrower types.
-  MVT SrcVT = TLI.getSimpleValueType(DL, I->getOperand(0)->getType());
+  EVT SrcVT = TLI.getValueType(DL, I->getOperand(0)->getType());
   if (SrcVT != MVT::i32 && SrcVT != MVT::i64)
     return false;
 

llvm/test/CodeGen/X86/pr68068.ll

@@ -0,0 +1,11 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=x86_64-- -fast-isel=1 | FileCheck %s
+
+define float @f() "target-features"="+avx512f" {
+; CHECK-LABEL: f:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    vxorps %xmm0, %xmm0, %xmm0
+; CHECK-NEXT:    retq
+  %1 = uitofp i15 poison to float
+  ret float %1
+}