[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
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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.