[clang] [compiler-rt] [ubsan] Display correct runtime messages for negative _BitInt (PR #93612)

[Paul Kirth via cfe-commits]

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@@ -0,0 +1,188 @@
+// RUN: %clang -Wno-constant-conversion -Wno-array-bounds -Wno-division-by-zero -Wno-shift-negative-value -Wno-shift-count-negative -Wno-int-to-pointer-cast -O0 -fsanitize=alignment,array-bounds,bool,float-cast-overflow,implicit-integer-sign-change,implicit-signed-integer-truncation,implicit-unsigned-integer-truncation,integer-divide-by-zero,nonnull-attribute,null,nullability-arg,nullability-assign,nullability-return,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,unsigned-integer-overflow,unsigned-shift-base,vla-bound %s -o %t1 && %run %t1 2>&1 | FileCheck %s --check-prefix=CHECK-R
+// RUN: %clang -Wno-constant-conversion -Wno-array-bounds -Wno-division-by-zero -Wno-shift-negative-value -Wno-shift-count-negative -Wno-int-to-pointer-cast -fsanitize=array-bounds,enum,float-cast-overflow,integer-divide-by-zero,implicit-unsigned-integer-truncation,implicit-signed-integer-truncation,implicit-integer-sign-change,unsigned-integer-overflow,signed-integer-overflow,shift-base,shift-exponent -O0 -S -emit-llvm -o - %s | FileCheck %s --check-prefix=CHECK-IR
----------------
ilovepi wrote:

Maybe use `RUNTIME` instead of `CHECK-R` and `IR` instead of `CHECK-IR`? The convention seems to be mixed in this dir, but I think its more typical to avoid the CHECK prefix in other parts of the project. This is a nit/suggestion, and I'm fine if you leave it as is.

```suggestion
// RUN: %clang -Wno-constant-conversion -Wno-array-bounds -Wno-division-by-zero -Wno-shift-negative-value -Wno-shift-count-negative -Wno-int-to-pointer-cast -O0 -fsanitize=alignment,array-bounds,bool,float-cast-overflow,implicit-integer-sign-change,implicit-signed-integer-truncation,implicit-unsigned-integer-truncation,integer-divide-by-zero,nonnull-attribute,null,nullability-arg,nullability-assign,nullability-return,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,unsigned-integer-overflow,unsigned-shift-base,vla-bound %s -o %t1 && %run %t1 2>&1 | FileCheck %s --check-prefix=RUNTIME
// RUN: %clang -Wno-constant-conversion -Wno-array-bounds -Wno-division-by-zero -Wno-shift-negative-value -Wno-shift-count-negative -Wno-int-to-pointer-cast -fsanitize=array-bounds,enum,float-cast-overflow,integer-divide-by-zero,implicit-unsigned-integer-truncation,implicit-signed-integer-truncation,implicit-integer-sign-change,unsigned-integer-overflow,signed-integer-overflow,shift-base,shift-exponent -O0 -S -emit-llvm -o - %s | FileCheck %s --check-prefix=IR
```

https://github.com/llvm/llvm-project/pull/93612