Use poison instead of undef.

Author: s-perron

clang/lib/CodeGen/CodeGenModule.cpp

@@ -5590,7 +5590,7 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
         T = D->getType();
 
       if (getLangOpts().HLSL && getHLSLRuntime().isResource(D)) {
-        Init = llvm::UndefValue::get(getTypes().ConvertType(ASTTy));
+        Init = llvm::PoisonValue::get(getTypes().ConvertType(ASTTy));
         NeedsGlobalCtor = true;
       } else if (getLangOpts().CPlusPlus) {
         Init = EmitNullConstant(T);

clang/test/CodeGenHLSL/builtins/ByteAddressBuffers-constructors.hlsl

@@ -11,9 +11,9 @@ RasterizerOrderedByteAddressBuffer Buffer2: register(u3, space4);
 // CHECK: "class.hlsl::RWByteAddressBuffer" = type { target("dx.RawBuffer", i8, 1, 0) }
 // CHECK: "class.hlsl::RasterizerOrderedByteAddressBuffer" = type { target("dx.RawBuffer", i8, 1, 1) }
 
-// CHECK: @Buffer0 = internal global %"class.hlsl::ByteAddressBuffer" undef, align 4
-// CHECK: @Buffer1 = internal global %"class.hlsl::RWByteAddressBuffer" undef, align 4
-// CHECK: @Buffer2 = internal global %"class.hlsl::RasterizerOrderedByteAddressBuffer" undef, align 4
+// CHECK: @Buffer0 = internal global %"class.hlsl::ByteAddressBuffer" poison, align 4
+// CHECK: @Buffer1 = internal global %"class.hlsl::RWByteAddressBuffer" poison, align 4
+// CHECK: @Buffer2 = internal global %"class.hlsl::RasterizerOrderedByteAddressBuffer" poison, align 4
 
 // CHECK; define internal void @_init_resource_Buffer0()
 // CHECK-DXIL: %Buffer0_h = call target("dx.RawBuffer", i8, 0, 0) @llvm.dx.resource.handlefrombinding.tdx.RawBuffer_i8_0_0t(i32 0, i32 0, i32 1, i32 0, i1 false)

clang/test/CodeGenHLSL/builtins/RWBuffer-constructor.hlsl

@@ -7,7 +7,7 @@
 RWBuffer<float> Buf : register(u5, space3);
 
 // CHECK: %"class.hlsl::RWBuffer" = type { target("dx.TypedBuffer", float, 1, 0, 0) }
-// CHECK: @Buf = internal global %"class.hlsl::RWBuffer" undef, align 4
+// CHECK: @Buf = internal global %"class.hlsl::RWBuffer" poison, align 4
 
 // CHECK: define internal void @_init_resource_Buf()
 // CHECK-DXIL: %Buf_h = call target("dx.TypedBuffer", float, 1, 0, 0) @llvm.dx.resource.handlefrombinding.tdx.TypedBuffer_f32_1_0_0t(i32 3, i32 5, i32 1, i32 0, i1 false)

clang/test/CodeGenHLSL/builtins/StructuredBuffers-constructors.hlsl

@@ -15,11 +15,11 @@ RasterizerOrderedStructuredBuffer<float> Buf5 : register(u1, space2);
 // CHECK: %"class.hlsl::ConsumeStructuredBuffer" = type { target("dx.RawBuffer", float, 1, 0) }
 // CHECK: %"class.hlsl::RasterizerOrderedStructuredBuffer" = type { target("dx.RawBuffer", float, 1, 1) }
 
-// CHECK: @Buf = internal global %"class.hlsl::StructuredBuffer" undef, align 4
-// CHECK: @Buf2 = internal global %"class.hlsl::RWStructuredBuffer" undef, align 4
-// CHECK: @Buf3 = internal global %"class.hlsl::AppendStructuredBuffer" undef, align 4
-// CHECK: @Buf4 = internal global %"class.hlsl::ConsumeStructuredBuffer" undef, align 4
-// CHECK: @Buf5 = internal global %"class.hlsl::RasterizerOrderedStructuredBuffer" undef, align 4
+// CHECK: @Buf = internal global %"class.hlsl::StructuredBuffer" poison, align 4
+// CHECK: @Buf2 = internal global %"class.hlsl::RWStructuredBuffer" poison, align 4
+// CHECK: @Buf3 = internal global %"class.hlsl::AppendStructuredBuffer" poison, align 4
+// CHECK: @Buf4 = internal global %"class.hlsl::ConsumeStructuredBuffer" poison, align 4
+// CHECK: @Buf5 = internal global %"class.hlsl::RasterizerOrderedStructuredBuffer" poison, align 4
 
 // CHECK: define internal void @_init_resource_Buf()
 // CHECK-DXIL: %Buf_h = call target("dx.RawBuffer", float, 0, 0) @llvm.dx.resource.handlefrombinding.tdx.RawBuffer_f32_0_0t(i32 0, i32 10, i32 1, i32 0, i1 false)