[llvm] [LowerMemIntrinsics] Use i8 GEPs in memcpy/memmove lowering (PR #112707)

[Pierre van Houtryve via llvm-commits]

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@@ -49,11 +49,12 @@ void llvm::createMemCpyLoopKnownSize(
   assert((!AtomicElementSize || !LoopOpType->isVectorTy()) &&
          "Atomic memcpy lowering is not supported for vector operand type");
 
+  Type *Int8Type = Type::getInt8Ty(Ctx);
   unsigned LoopOpSize = DL.getTypeStoreSize(LoopOpType);
   assert((!AtomicElementSize || LoopOpSize % *AtomicElementSize == 0) &&
-      "Atomic memcpy lowering is not supported for selected operand size");
+         "Atomic memcpy lowering is not supported for selected operand size");
 
-  uint64_t LoopEndCount = CopyLen->getZExtValue() / LoopOpSize;
+  uint64_t LoopEndCount = (CopyLen->getZExtValue() / LoopOpSize) * LoopOpSize;
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Pierre-vh wrote:

Why does this divides then multiplies by the same number? 

https://github.com/llvm/llvm-project/pull/112707