[llvm-branch-commits] [llvm] [SPIRV][SPIRVPrepareGlobals] Map AMD's dynamic LDS 0-element globals to arrays with UINT32_MAX elements (PR #166952)

[Steven Perron via llvm-branch-commits]

Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/166952 at github.com>


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@@ -43,6 +44,29 @@ bool tryExtendLLVMBitcodeMarker(GlobalVariable &Bitcode) {
   return true;
 }
 
+bool tryExtendDynamicLDSGlobal(GlobalVariable &GV) {
+  constexpr unsigned WorkgroupAS = 3;
+  const bool IsWorkgroupExternal =
+      GV.hasExternalLinkage() && GV.getAddressSpace() == WorkgroupAS;
+  if (!IsWorkgroupExternal)
+    return false;
+
+  const ArrayType *AT = dyn_cast<ArrayType>(GV.getValueType());
+  if (!AT || AT->getNumElements() != 0)
+    return false;
----------------
s-perron wrote:

Sorry, I did not write that properly.

Could you have, say, a global whose type is a struct containing a 0-sized array? What do you want to do in case?

```
@lds = external addrspace(3) global {i32, [0 x i32]}
```

https://github.com/llvm/llvm-project/pull/166952