[llvm] [DirectX] Add support for implicit binding to DXILForwardHandleAccesses pass (PR #142061)

[Helena Kotas via llvm-commits]

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@@ -1,9 +1,11 @@
 ; RUN: opt -S -dxil-forward-handle-accesses -mtriple=dxil--shadermodel6.3-library %s | FileCheck %s
 
 %__cblayout_CB = type <{ float, i32, i32 }>
+%__cblayout_CB2 = type <{ float }>
 %struct.Scalars = type { float, i32, i32 }
 
 @CB.cb = local_unnamed_addr global target("dx.CBuffer", target("dx.Layout", %__cblayout_CB, 12, 0, 4, 8)) poison
+ at CB2.cb = local_unnamed_addr global target("dx.CBuffer", target("dx.Layout", %__cblayout_CB2, 4, 0)) poison
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hekota wrote:

The list of numbers in "dx.Layout" target type encodes its size and layout - the first number is the size of the structure followed by a list of byte offsets of each field. Since`__cblayout_CB` struct has 3 fields, it has more numbers than `__cblayout_CB2` with just one field.    

https://github.com/llvm/llvm-project/pull/142061