[llvm] CallPromotionUtils: Correctly use IndexSize when determining the bit width of pointer offsets. (PR #119483)

[Owen Anderson via llvm-commits]

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@@ -712,7 +712,12 @@ bool llvm::tryPromoteCall(CallBase &CB) {
       VTablePtrLoad, VTablePtrLoad->getParent(), BBI, 0, nullptr, nullptr);
   if (!VTablePtr)
     return false; // No vtable found.
-  APInt VTableOffsetGVBase(DL.getTypeSizeInBits(VTablePtr->getType()), 0);
+
+  // VTablePtr may not actually have a pointer type, so we can't find the
+  // address space through it. However, we know that the address space must be
+  // the same one used to load from the vtable in VTablePtrLoad.
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resistor wrote:

Revised to implement this fix instead.

https://github.com/llvm/llvm-project/pull/119483