[clang] [llvm] [IR] Require DataLayout for pointer cast elimination (PR #162279)

[Nikita Popov via llvm-commits]

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@@ -139,11 +139,12 @@ define i128 @ptrtoint_gep_sub_wide_type(ptr %ptr, i128 %end.addr) {
   ret i128 %end.addr2
 }
 
-; FIXME: This is a miscompile.
 define ptr addrspace(1) @inttoptr_of_ptrtoint_wide(ptr addrspace(1) %ptr) {
 ; CHECK-LABEL: define ptr addrspace(1) @inttoptr_of_ptrtoint_wide(
 ; CHECK-SAME: ptr addrspace(1) [[PTR:%.*]]) {
-; CHECK-NEXT:    ret ptr addrspace(1) [[PTR]]
+; CHECK-NEXT:    [[INT:%.*]] = ptrtoint ptr addrspace(1) [[PTR]] to i64
+; CHECK-NEXT:    [[PTR2:%.*]] = inttoptr i64 [[INT]] to ptr addrspace(1)
+; CHECK-NEXT:    ret ptr addrspace(1) [[PTR2]]
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nikic wrote:

This illustrates the miscompile.

https://github.com/llvm/llvm-project/pull/162279