[llvm] [SPIRV] Enable DCE in instruction selection and update tests (PR #168428)

[Farzon Lotfi via llvm-commits]

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@@ -4,18 +4,23 @@
 
 @.str = private unnamed_addr constant [7 x i8] c"buffer\00", align 1
 
+; The i64 values in the extracts will be turned
+; into immidiate values. There should be no 64-bit
+; integers in the module.
+; CHECK-NOT:  OpTypeInt 64 0
+
 define void @main() "hlsl.shader"="pixel"  {
-; CHECK:         %24 = OpFunction %2 None %3 ; -- Begin function main
-; CHECK-NEXT:     %1 = OpLabel
-; CHECK-NEXT:    %25 = OpVariable %13 Function %22
-; CHECK-NEXT:    %26 = OpLoad %7 %23
-; CHECK-NEXT:    %27 = OpImageRead %5 %26 %15
-; CHECK-NEXT:    %28 = OpCompositeExtract %4 %27 0
-; CHECK-NEXT:    %29 = OpCompositeExtract %4 %27 1
-; CHECK-NEXT:    %30 = OpFAdd %4 %29 %28
-; CHECK-NEXT:    %31 = OpCompositeInsert %5 %30 %27 0
-; CHECK-NEXT:    %32 = OpLoad %7 %23
-; CHECK-NEXT:          OpImageWrite %32 %15 %31
+; CHECK:         %[[FUNC:[0-9]+]] = OpFunction %[[VOID:[0-9]+]] None %[[FNTYPE:[0-9]+]] ; -- Begin function main
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farzonl wrote:

thank you for this improvement.

https://github.com/llvm/llvm-project/pull/168428