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

[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
+
+#include <stdint.h>
+#include <stdio.h>
+
+uint32_t float_divide_by_zero() {
+  float f = 1.0f / 0.0f;
+  // CHECK-IR: constant { i16, i16, [8 x i8] } { i16 1, i16 32, [8 x i8] c"'float'\00" }
+  _BitInt(37) r = (_BitInt(37))f;
+  // CHECK-R: {{.*}}bit-int.c:[[@LINE-1]]:19: runtime error: inf is outside the range of representable values of type
+  // CHECK-IR: constant { i16, i16, [20 x i8] } { i16 2, i16 13, [20 x i8] c"'_BitInt(37)'\00%\00\00\00\00\00" }
+  return r;
+}
+
+uint32_t integer_divide_by_zero() __attribute__((no_sanitize("memory"))) {
+  _BitInt(37) x = 1 / 0;
+  // CHECK-R: {{.*}}bit-int.c:[[@LINE-1]]:21: runtime error: division by zero
+  // CHECK-IR: constant { i16, i16, [32 x i8] } { i16 0, i16 10, [32 x i8] c"'uint32_t' (aka 'unsigned int')\00" }
+  return x;
+}
+
+uint32_t implicit_unsigned_integer_truncation() {
+  unsigned _BitInt(37) x = 2U;
+  x += float_divide_by_zero();
+  x += integer_divide_by_zero();
+  x = x + 0xFFFFFFFFFFFFFFFFULL;
+  // CHECK-R: {{.*}}bit-int.c:[[@LINE-1]]:9: runtime error: unsigned integer overflow:
+  // CHECK-IR: constant { i16, i16, [23 x i8] } { i16 0, i16 12, [23 x i8] c"'unsigned _BitInt(37)'\00" }
+  uint32_t r = x & 0xFFFFFFFF;
+  return r;
+}
+
+uint32_t pointer_overflow() __attribute__((no_sanitize("address"))) {
+  _BitInt(37) *x = (_BitInt(37) *)1;
+  _BitInt(37) *y = x - 1;
+  // CHECK-R: {{.*}}bit-int.c:[[@LINE-1]]:22: runtime error: pointer index expression with base
+  uint32_t r = *(_BitInt(37) *)&y;
+  // CHECK-R: {{.*}}bit-int.c:[[@LINE-1]]:16: runtime error: implicit conversion from type
+  return r;
+}
+
+uint32_t vla_bound(_BitInt(37) x) {
+  _BitInt(37) a[x - 1];
+  // CHECK-R: {{.*}}bit-int.c:[[@LINE-1]]:17: runtime error: variable length array bound evaluates to non-positive value
+  return 0;
+}
+
+uint32_t nullability_arg(_BitInt(37) *_Nonnull x)
+    __attribute__((no_sanitize("address"))) {
+  _BitInt(37) y = *(_BitInt(37) *)&x;
+  return y;
+}
----------------
earnol wrote:

Oh... Just seen your response. Do you want me to change it into "-fsanitize-trap" or the current implementation is fine?
For me whatever diagnostics is displayed is having "runtime error" so while line is not known in advance we are pretty sure about part of the line and it can be entered into CHECK-NOT. 

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