[InstCombine] Extra null-checking on TFE/LWE support

- If that operand is not ConstantInt, skip enabling TFE/LWE.

Differential Revision: https://reviews.llvm.org/D57539

llvm-svn: 352904

llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp

@@ -975,12 +975,11 @@ Value *InstCombiner::simplifyAMDGCNMemoryIntrinsicDemanded(IntrinsicInst *II,
     return nullptr;
 
   // Need to change to new instruction format
-  ConstantInt *TFC = nullptr;
   bool TFELWEEnabled = false;
   if (TFCIdx > 0) {
-    TFC = dyn_cast<ConstantInt>(II->getArgOperand(TFCIdx));
-    TFELWEEnabled =    TFC->getZExtValue() & 0x1  // TFE
-                    || TFC->getZExtValue() & 0x2; // LWE
+    if (ConstantInt *TFC = dyn_cast<ConstantInt>(II->getArgOperand(TFCIdx)))
+      TFELWEEnabled =    TFC->getZExtValue() & 0x1  // TFE
+                      || TFC->getZExtValue() & 0x2; // LWE
   }
 
   if (TFELWEEnabled)

llvm/test/Transforms/InstCombine/AMDGPU/amdgcn-demanded-vector-elts.ll

@@ -2395,7 +2395,14 @@ define amdgpu_ps float @extract_elt0_image_getresinfo_1d_v4f32_i32(i32 %mip, <8
   ret float %elt0
 }
 
+; Verify that we don't creash on non-constant operand.
+define protected <4 x half> @__llvm_amdgcn_image_sample_d_1darray_v4f16_f32_f32(i32, float, float, float, float, <8 x i32>, <4 x i32>, i1 zeroext, i32, i32) local_unnamed_addr {
+  %tmp = tail call <4 x half> @llvm.amdgcn.image.sample.d.1darray.v4f16.f32.f32(i32 %0, float %1, float %2, float %3, float %4, <8 x i32> %5, <4 x i32> %6, i1 zeroext %7, i32 %8, i32 %9) #1
+  ret <4 x half> %tmp
+}
+
 declare <4 x float> @llvm.amdgcn.image.getresinfo.1d.v4f32.i32(i32, i32, <8 x i32>, i32, i32) #1
+declare <4 x half> @llvm.amdgcn.image.sample.d.1darray.v4f16.f32.f32(i32, float, float, float, float, <8 x i32>, <4 x i32>, i1, i32, i32)
 
 attributes #0 = { nounwind }
 attributes #1 = { nounwind readonly }