[clang] [sanitizer] Parse weighted sanitizer args and -fno-sanitize-top-hot (PR #121619)

[Vitaly Buka via cfe-commits]

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@@ -1154,3 +1154,56 @@
 
 // RUN: not %clang --target=x86_64-linux-gnu -fsanitize=realtime,undefined  %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-REALTIME-UBSAN
 // CHECK-REALTIME-UBSAN: error: invalid argument '-fsanitize=realtime' not allowed with '-fsanitize=undefined'
+
+
+// * Test -fno-sanitize-top-hot *
+
+// -fno-sanitize-top-hot=undefined=0.5
+// RUN: %clang -Werror --target=x86_64-linux-gnu -fsanitize=undefined -fno-sanitize-top-hot=undefined=0.5 %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TOP-HOT1
+// CHECK-TOP-HOT1: "-fno-sanitize-top-hot={{((signed-integer-overflow|integer-divide-by-zero|shift-base|shift-exponent|unreachable|return|vla-bound|alignment|null|pointer-overflow|float-cast-overflow|array-bounds|enum|bool|builtin|returns-nonnull-attribute|nonnull-attribute|function|vptr)=0.5(0*),?){19}"}}
+
+// No-op: no sanitizers are specified
+// RUN: %clang -Werror --target=x86_64-linux-gnu -fno-sanitize-top-hot=undefined=0.5 %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TOP-HOT2
+// CHECK-TOP-HOT2-NOT: "-fsanitize"
+// CHECK-TOP-HOT2-NOT: "-fno-sanitize-top-hot"
+
+// Enable undefined, then cancel out integer using a cutoff of 0.0
+// RUN: %clang -Werror --target=x86_64-linux-gnu -fsanitize=undefined -fno-sanitize-top-hot=undefined=0.5,integer=0.0 %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TOP-HOT3
+// CHECK-TOP-HOT3: "-fno-sanitize-top-hot={{((unreachable|return|vla-bound|alignment|null|pointer-overflow|float-cast-overflow|array-bounds|enum|bool|builtin|returns-nonnull-attribute|nonnull-attribute|function|vptr)=0.5(0*),?){15}"}}
+
+// Enable undefined, then cancel out integer using a cutoff of 0.0, then re-enable signed-integer-overflow
+// RUN: %clang -Werror --target=x86_64-linux-gnu -fsanitize=undefined -fno-sanitize-top-hot=undefined=0.5,integer=0.0,signed-integer-overflow=0.7 %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TOP-HOT4
+// CHECK-TOP-HOT4: "-fno-sanitize-top-hot={{((signed-integer-overflow|unreachable|return|vla-bound|alignment|null|pointer-overflow|float-cast-overflow|array-bounds|enum|bool|builtin|returns-nonnull-attribute|nonnull-attribute|function|vptr)=(0.5|0.49|0.7|0.69)([0-9]*),?){16}"}}
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vitalybuka wrote:

According to C standard "the value is rounded to the appropriate number of digits.",
So 4 and 6 now are impossible.

https://github.com/llvm/llvm-project/pull/121619