[llvm] [SPIR-V] Fix division by zero on byte addressing GEP into a subbyte array (PR #202593)

[Arseniy Obolenskiy via llvm-commits]

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@@ -788,7 +788,7 @@ bool SPIRVEmitIntrinsics::walkLogicalAccessChainConstant(
 
   do {
     if (ArrayType *AT = dyn_cast<ArrayType>(CurType)) {
-      uint32_t EltTypeSize = DL.getTypeSizeInBits(AT->getElementType()) / 8;
+      uint64_t EltTypeSize = DL.getTypeAllocSize(AT->getElementType());
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aobolensk wrote:

`getTypeAllocSize` depends on LLVM IR DataLayout, not on SPIR-V expectations

https://github.com/llvm/llvm-project/pull/202593