mstorsjo wrote: With https://martin.st/temp/abs-preproc.cpp as input, I run `clang -target i686-w64-mingw32 abs-preproc.cpp -fsanitize=signed-integer-overflow -w -O3 -S -emit-llvm -o abs-out.ll`, and I get the following diff of the output IR after this change: ```diff --- abs-good.ll 2025-04-20 00:10:20.155904358 +0300 +++ abs-bad.ll 2025-04-20 00:10:30.432882049 +0300 @@ -14,7 +14,7 @@ @7 = private unnamed_addr global { { ptr, i32, i32 }, ptr } { { ptr, i32, i32 } { ptr @.src, i32 481, i32 19 }, ptr @6 } @8 = private unnamed_addr global { { ptr, i32, i32 }, ptr } { { ptr, i32, i32 } { ptr @.src, i32 482, i32 9 }, ptr @6 } -; Function Attrs: mustprogress norecurse nounwind +; Function Attrs: mustprogress norecurse nounwind memory(read, argmem: none, inaccessiblemem: readwrite) define dso_local noundef i32 @main() local_unnamed_addr #0 { entry: %tmp = alloca i64, align 8 @@ -23,20 +23,18 @@ tail call void @__ubsan_handle_negate_overflow(ptr nonnull @2, i32 -2147483648) #2, !nosanitize !6 tail call void @__ubsan_handle_negate_overflow(ptr nonnull @4, i32 -2147483648) #2, !nosanitize !6 tail call void @__ubsan_handle_negate_overflow(ptr nonnull @5, i32 -2147483648) #2, !nosanitize !6 - store i64 -9223372036854775808, ptr %tmp, align 8, !nosanitize !6 %0 = ptrtoint ptr %tmp to i32, !nosanitize !6 call void @__ubsan_handle_negate_overflow(ptr nonnull @7, i32 %0) #2, !nosanitize !6 - store i64 -9223372036854775808, ptr %tmp14, align 8, !nosanitize !6 %1 = ptrtoint ptr %tmp14 to i32, !nosanitize !6 call void @__ubsan_handle_negate_overflow(ptr nonnull @8, i32 %1) #2, !nosanitize !6 ret i32 0 } -; Function Attrs: uwtable +; Function Attrs: memory(argmem: read, inaccessiblemem: readwrite) uwtable declare dso_local void @__ubsan_handle_negate_overflow(ptr, i32) local_unnamed_addr #1 -attributes #0 = { mustprogress norecurse nounwind "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="pentium4" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" } -attributes #1 = { uwtable } +attributes #0 = { mustprogress norecurse nounwind memory(read, argmem: none, inaccessiblemem: readwrite) "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="pentium4" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" } +attributes #1 = { memory(argmem: read, inaccessiblemem: readwrite) uwtable } attributes #2 = { nounwind } !llvm.module.flags = !{!0, !1, !2} ```
https://github.com/llvm/llvm-project/pull/135135 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
