[ubsan] Remove -ubsan-unique-traps (replace with -fno-sanitize-merge) #120613
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-fno-sanitize-merge (introduced in llvm#120511) duplicates the functionality of -ubsan-unique-traps but also allows individual checks to be specified e.g., * "-fno-sanitize-merge" without arguments is equivalent to -ubsan-unique-traps * "-fno-sanitize-merge=bool,enum" will apply it only to those two checks This patch also adds negative test examples to bounds-checking.c, and strengthens the NOOPTARRAY assertion to prevent spurious matches. Note: this change necessarily breaks compatibility with '-mllvm -ubsan-unique-traps'. We hope that this is acceptable since '-mllvm -ubsan-unique-traps' was an experimental flag. "-bounds-checking-unique-traps" is unaffected by this patch.
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| @llvm/pr-subscribers-clang-codegen @llvm/pr-subscribers-clang Author: Thurston Dang (thurstond) Changes-fno-sanitize-merge (introduced in #120511) duplicates the functionality of -ubsan-unique-traps but also allows individual checks to be specified e.g.,
This patch also adds negative test examples to bounds-checking.c, and strengthens the NOOPTARRAY assertion to prevent spurious matches. Note: this change necessarily breaks compatibility with '-mllvm -ubsan-unique-traps'. We hope that this is acceptable since '-mllvm -ubsan-unique-traps' was an experimental flag. "-bounds-checking-unique-traps" is unaffected by this patch. Full diff: https://github.com/llvm/llvm-project/pull/120613.diff 3 Files Affected:
diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp index d3fa5be6777ef4..ba1cba291553b0 100644 --- a/clang/lib/CodeGen/CGExpr.cpp +++ b/clang/lib/CodeGen/CGExpr.cpp @@ -52,11 +52,6 @@ using namespace clang; using namespace CodeGen; -// Experiment to make sanitizers easier to debug -static llvm::cl::opt<bool> ClSanitizeDebugDeoptimization( - "ubsan-unique-traps", llvm::cl::Optional, - llvm::cl::desc("Deoptimize traps for UBSAN so there is 1 trap per check.")); - // TODO: Introduce frontend options to enabled per sanitizers, similar to // `fsanitize-trap`. static llvm::cl::opt<bool> ClSanitizeGuardChecks( @@ -3581,8 +3576,7 @@ static void emitCheckHandlerCall(CodeGenFunction &CGF, llvm::AttributeList::FunctionIndex, B), /*Local=*/true); llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs); - NoMerge = NoMerge || ClSanitizeDebugDeoptimization || - !CGF.CGM.getCodeGenOpts().OptimizationLevel || + NoMerge = NoMerge || !CGF.CGM.getCodeGenOpts().OptimizationLevel || (CGF.CurCodeDecl && CGF.CurCodeDecl->hasAttr<OptimizeNoneAttr>()); if (NoMerge) HandlerCall->addFnAttr(llvm::Attribute::NoMerge); @@ -3915,8 +3909,7 @@ void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked, llvm::BasicBlock *&TrapBB = TrapBBs[CheckHandlerID]; - NoMerge = NoMerge || ClSanitizeDebugDeoptimization || - !CGM.getCodeGenOpts().OptimizationLevel || + NoMerge = NoMerge || !CGM.getCodeGenOpts().OptimizationLevel || (CurCodeDecl && CurCodeDecl->hasAttr<OptimizeNoneAttr>()); if (TrapBB && !NoMerge) { diff --git a/clang/test/CodeGen/bounds-checking.c b/clang/test/CodeGen/bounds-checking.c index f6c4880e70a150..caab302fdf7956 100644 --- a/clang/test/CodeGen/bounds-checking.c +++ b/clang/test/CodeGen/bounds-checking.c @@ -1,7 +1,15 @@ -// RUN: %clang_cc1 -fsanitize=local-bounds -emit-llvm -triple x86_64-apple-darwin10 %s -o - | FileCheck %s -// RUN: %clang_cc1 -fsanitize=array-bounds -O -fsanitize-trap=array-bounds -emit-llvm -triple x86_64-apple-darwin10 -DNO_DYNAMIC %s -o - | FileCheck %s -// RUN: %clang_cc1 -fsanitize=local-bounds -fsanitize-trap=local-bounds -O3 -mllvm -bounds-checking-unique-traps -emit-llvm -triple x86_64-apple-darwin10 %s -o - | FileCheck %s --check-prefixes=NOOPTLOCAL -// RUN: %clang_cc1 -fsanitize=array-bounds -fsanitize-trap=array-bounds -O3 -mllvm -ubsan-unique-traps -emit-llvm -triple x86_64-apple-darwin10 %s -o - | FileCheck %s --check-prefixes=NOOPTARRAY +// RUN: %clang_cc1 -fsanitize=local-bounds -emit-llvm -triple x86_64-apple-darwin10 %s -o - | FileCheck %s +// RUN: %clang_cc1 -fsanitize=array-bounds -O -emit-llvm -triple x86_64-apple-darwin10 %s -o - | not FileCheck %s +// RUN: %clang_cc1 -fsanitize=array-bounds -O -fsanitize-trap=array-bounds -emit-llvm -triple x86_64-apple-darwin10 -DNO_DYNAMIC %s -o - | FileCheck %s +// +// RUN: %clang_cc1 -fsanitize=local-bounds -fsanitize-trap=local-bounds -O3 -mllvm -bounds-checking-unique-traps -emit-llvm -triple x86_64-apple-darwin10 %s -o - | FileCheck %s --check-prefixes=NOOPTLOCAL +// RUN: %clang_cc1 -fsanitize=local-bounds -fsanitize-trap=local-bounds -O3 -emit-llvm -triple x86_64-apple-darwin10 %s -o - | not FileCheck %s --check-prefixes=NOOPTLOCAL +// +// N.B. The clang driver defaults to -fsanitize-merge but clang_cc1 effectively +// defaults to -fno-sanitize-merge. +// RUN: %clang_cc1 -fsanitize=array-bounds -fsanitize-trap=array-bounds -O3 -emit-llvm -triple x86_64-apple-darwin10 %s -o - | FileCheck %s --check-prefixes=NOOPTARRAY +// RUN: %clang_cc1 -fsanitize=array-bounds -fsanitize-trap=array-bounds -fno-sanitize-merge -O3 -emit-llvm -triple x86_64-apple-darwin10 %s -o - | FileCheck %s --check-prefixes=NOOPTARRAY +// RUN: %clang_cc1 -fsanitize=array-bounds -fsanitize-trap=array-bounds -fsanitize-merge=array-bounds -O3 -emit-llvm -triple x86_64-apple-darwin10 %s -o - | not FileCheck %s --check-prefixes=NOOPTARRAY // // REQUIRES: x86-registered-target @@ -43,7 +51,7 @@ int f4(int i) { return b[i]; } -// Union flexible-array memebers are a C99 extension. All array members with a +// Union flexible-array members are a C99 extension. All array members with a // constant size should be considered FAMs. union U { int a[0]; int b[1]; int c[2]; }; @@ -72,6 +80,10 @@ int f7(union U *u, int i) { char B[10]; char B2[10]; // CHECK-LABEL: @f8 +// Check the label to prevent spuriously matching ubsantraps from other +// functions. +// NOOPTLOCAL-LABEL: @f8 +// NOOPTARRAY-LABEL: @f8 void f8(int i, int k) { // NOOPTLOCAL: call void @llvm.ubsantrap(i8 3) // NOOPTARRAY: call void @llvm.ubsantrap(i8 18) diff --git a/clang/test/CodeGen/ubsan-trap-merge.c b/clang/test/CodeGen/ubsan-trap-merge.c index f211150a09cb67..486aa55f5b8119 100644 --- a/clang/test/CodeGen/ubsan-trap-merge.c +++ b/clang/test/CodeGen/ubsan-trap-merge.c @@ -10,10 +10,6 @@ // RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -fsanitize=signed-integer-overflow -O3 %s -o - | FileCheck %s --check-prefixes=HANDLER-NOMERGE // RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -fsanitize=signed-integer-overflow -O3 %s -o - -fsanitize-minimal-runtime | FileCheck %s --check-prefixes=MINRT-NOMERGE // -// RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -fsanitize=signed-integer-overflow -O3 -mllvm -ubsan-unique-traps %s -o - -fsanitize-trap=signed-integer-overflow | FileCheck %s --check-prefixes=TRAP-NOMERGE -// RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -fsanitize=signed-integer-overflow -O3 -mllvm -ubsan-unique-traps %s -o - | FileCheck %s --check-prefixes=HANDLER-NOMERGE -// RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -fsanitize=signed-integer-overflow -O3 -mllvm -ubsan-unique-traps %s -o - -fsanitize-minimal-runtime | FileCheck %s --check-prefixes=MINRT-NOMERGE -// // RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -fsanitize=signed-integer-overflow -O3 -fno-sanitize-merge=signed-integer-overflow %s -o - -fsanitize-trap=signed-integer-overflow | FileCheck %s --check-prefixes=TRAP-NOMERGE // RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -fsanitize=signed-integer-overflow -O3 -fno-sanitize-merge=signed-integer-overflow %s -o - | FileCheck %s --check-prefixes=HANDLER-NOMERGE // RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -fsanitize=signed-integer-overflow -O3 -fno-sanitize-merge=signed-integer-overflow %s -o - -fsanitize-minimal-runtime | FileCheck %s --check-prefixes=MINRT-NOMERGE |
oskarwirga approved these changes Dec 19, 2024
kstoimenov approved these changes Dec 19, 2024
thurstond added a commit to thurstond/llvm-project that referenced this pull request Dec 20, 2024
…e=local-bounds) -fno-sanitize-merge (introduced in llvm#120511) combines the functionality of -ubsan-unique-traps and -bounds-checking-unique-traps, while allowing fine-grained control of which UBSan checks to prevent merging. llvm#120613 removed -ubsan-unique-traps. This patch removes -bound-checking-unique-traps, which can be controlled via -fno-sanitize-merge=local-bounds. Note: this patch subtly changes -fsanitize-merge (the default) to also include -fsanitize-merge=local-bounds. This is different from the previous behavior, where -fsanitize-merge (or the old -ubsan-unique-traps) did not affect local-bounds (requiring the separate -bounds-checking-unique-traps). However, we argue that the new behavior is more intuitive. Removing -bounds-checking-unique-traps and merging its functionality into -fsanitize-merge breaks backwards compatibility; we hope that this is acceptable since '-mllvm -bounds-checking-unique-traps' was an experimental flag.
thurstond added a commit that referenced this pull request Dec 20, 2024
…e=local-bounds) (#120682) #120613 removed -ubsan-unique-traps and replaced it with -fno-sanitize-merge (introduced in #120511), which allows fine-grained control of which UBSan checks to prevent merging. This analogous patch removes -bound-checking-unique-traps, and allows it to be controlled via -fno-sanitize-merge=local-bounds. Most of this patch is simply plumbing through the compiler flags into the bounds checking pass. Note: this patch subtly changes -fsanitize-merge (the default) to also include -fsanitize-merge=local-bounds. This is different from the previous behavior, where -fsanitize-merge (or the old -ubsan-unique-traps) did not affect local-bounds (requiring the separate -bounds-checking-unique-traps). However, we argue that the new behavior is more intuitive. Removing -bounds-checking-unique-traps and merging its functionality into -fsanitize-merge breaks backwards compatibility; we hope that this is acceptable since '-mllvm -bounds-checking-unique-traps' was an experimental flag.
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-fno-sanitize-merge (introduced in #120511) duplicates the functionality of -ubsan-unique-traps but also allows individual checks to be specified e.g.,
Additionally, the naming is more consistent with the rest of the -fsanitize- family.
This patch therefore removes -ubsan-unique-traps. This breaks backwards compatibility; we hope that this is acceptable since '-mllvm -ubsan-unique-traps' was an experimental flag.
This patch also adds negative test examples to bounds-checking.c, and strengthens the NOOPTARRAY assertion to prevent spurious matches.
"-bounds-checking-unique-traps" is unaffected by this patch.