[clang] [HLSL] Support packoffset attribute in AST (PR #89836)

[Xiang Li via cfe-commits]

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@@ -0,0 +1,55 @@
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.3-library -verify %s
+
+// expected-error at +1{{cannot mix packoffset elements with nonpackoffset elements in a cbuffer}}
+cbuffer Mix
+{
+    float4 M1 : packoffset(c0);
+    float M2;
+    float M3 : packoffset(c1.y);
+}
+
+// expected-error at +1{{cannot mix packoffset elements with nonpackoffset elements in a cbuffer}}
+cbuffer Mix2
+{
+    float4 M4;
+    float M5 : packoffset(c1.y);
+    float M6 ;
+}
+
+// expected-error at +1{{attribute 'packoffset' only applies to cbuffer constant}}
+float4 g : packoffset(c0);
+
+cbuffer IllegalOffset
+{
+    // expected-error at +1{{invalid resource class specifier 't2' for packoffset, expected 'c'}}
+    float4 i1 : packoffset(t2);
+    // expected-error at +1{{invalid component 'm' used; expected 'x', 'y', 'z', or 'w'}}
+    float i2 : packoffset(c1.m);
+}
+
+cbuffer Overlap
+{
+    float4 o1 : packoffset(c0);
+    // expected-error at +1{{packoffset overlap between 'o2', 'o1'}}
+    float2 o2 : packoffset(c0.z);
+}
+
+cbuffer CrossReg
+{
+    // expected-error at +1{{packoffset cannot cross register boundary}}
+    float4 c1 : packoffset(c0.y);
+    // expected-error at +1{{packoffset cannot cross register boundary}}
+    float2 c2 : packoffset(c1.w);
+}
+
+struct ST {
+  float s;
+};
+
+cbuffer Aggregate
+{
+    // expected-error at +1{{packoffset cannot cross register boundary}}
+    ST A1 : packoffset(c0.y);
+    // expected-error at +1{{packoffset cannot cross register boundary}}
+    float A2[2] : packoffset(c1.w);
+}
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python3kgae wrote:

Updated.

https://github.com/llvm/llvm-project/pull/89836