[ubsan] Pass fsanitize-skip-hot-cutoff into -fsanitize=bounds (#122576)

Author: vitalybuka

clang/lib/CodeGen/BackendUtil.cpp

@@ -85,6 +85,7 @@
 #include "llvm/Transforms/Scalar/JumpThreading.h"
 #include "llvm/Transforms/Utils/Debugify.h"
 #include "llvm/Transforms/Utils/ModuleUtils.h"
+#include <limits>
 #include <memory>
 #include <optional>
 using namespace clang;
@@ -119,6 +120,9 @@ static cl::opt<PGOOptions::ColdFuncOpt> ClPGOColdFuncAttr(
 
 extern cl::opt<InstrProfCorrelator::ProfCorrelatorKind> ProfileCorrelate;
 } // namespace llvm
+namespace clang {
+extern llvm::cl::opt<bool> ClSanitizeGuardChecks;
+}
 
 namespace {
 
@@ -1023,6 +1027,14 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
       PB.registerScalarOptimizerLateEPCallback([this](FunctionPassManager &FPM,
                                                       OptimizationLevel Level) {
         BoundsCheckingPass::Options Options;
+        if (CodeGenOpts.SanitizeSkipHotCutoffs[SanitizerKind::SO_LocalBounds] ||
+            ClSanitizeGuardChecks) {
+          static_assert(SanitizerKind::SO_LocalBounds <=
+                            std::numeric_limits<
+                                decltype(Options.GuardKind)::value_type>::max(),
+                        "Update type of llvm.allow.ubsan.check.");
+          Options.GuardKind = SanitizerKind::SO_LocalBounds;
+        }
         Options.Merge =
             CodeGenOpts.SanitizeMergeHandlers.has(SanitizerKind::LocalBounds);
         if (!CodeGenOpts.SanitizeTrap.has(SanitizerKind::LocalBounds)) {

clang/lib/CodeGen/CGExpr.cpp

@@ -52,11 +52,13 @@
 using namespace clang;
 using namespace CodeGen;
 
+namespace clang {
 // TODO: Introduce frontend options to enabled per sanitizers, similar to
 // `fsanitize-trap`.
-static llvm::cl::opt<bool> ClSanitizeGuardChecks(
+llvm::cl::opt<bool> ClSanitizeGuardChecks(
     "ubsan-guard-checks", llvm::cl::Optional,
     llvm::cl::desc("Guard UBSAN checks with `llvm.allow.ubsan.check()`."));
+} // namespace clang
 
 //===--------------------------------------------------------------------===//
 //                        Defines for metadata

clang/test/CodeGen/allow-ubsan-check.c

@@ -174,12 +174,14 @@ void use(double*);
 // CHECK-NEXT:    [[VLA:%.*]] = alloca double, i64 [[TMP0]], align 16
 // CHECK-NEXT:    call void @use(ptr noundef nonnull [[VLA]]) #[[ATTR7:[0-9]+]]
 // CHECK-NEXT:    [[IDXPROM:%.*]] = sext i32 [[I]] to i64
-// CHECK-NEXT:    [[DOTNOT:%.*]] = icmp ugt i64 [[TMP0]], [[IDXPROM]]
-// CHECK-NEXT:    br i1 [[DOTNOT]], label %[[BB1:.*]], label %[[TRAP:.*]]
-// CHECK:       [[BB1]]:
+// CHECK-NEXT:    [[TMP1:%.*]] = icmp ule i64 [[TMP0]], [[IDXPROM]]
+// CHECK-NEXT:    [[TMP2:%.*]] = call i1 @llvm.allow.ubsan.check(i8 71), !nosanitize [[META2]]
+// CHECK-NEXT:    [[TMP3:%.*]] = and i1 [[TMP1]], [[TMP2]], !nosanitize [[META2]]
+// CHECK-NEXT:    br i1 [[TMP3]], label %[[TRAP:.*]], label %[[BB4:.*]]
+// CHECK:       [[BB4]]:
 // CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds double, ptr [[VLA]], i64 [[IDXPROM]]
-// CHECK-NEXT:    [[TMP2:%.*]] = load double, ptr [[ARRAYIDX]], align 8, !tbaa [[TBAA8:![0-9]+]]
-// CHECK-NEXT:    ret double [[TMP2]]
+// CHECK-NEXT:    [[TMP5:%.*]] = load double, ptr [[ARRAYIDX]], align 8, !tbaa [[TBAA8:![0-9]+]]
+// CHECK-NEXT:    ret double [[TMP5]]
 // CHECK:       [[TRAP]]:
 // CHECK-NEXT:    call void @__ubsan_handle_local_out_of_bounds_abort() #[[ATTR6]], !nosanitize [[META2]]
 // CHECK-NEXT:    unreachable, !nosanitize [[META2]]
@@ -191,12 +193,14 @@ void use(double*);
 // TR-NEXT:    [[VLA:%.*]] = alloca double, i64 [[TMP0]], align 16
 // TR-NEXT:    call void @use(ptr noundef nonnull [[VLA]]) #[[ATTR6:[0-9]+]]
 // TR-NEXT:    [[IDXPROM:%.*]] = sext i32 [[I]] to i64
-// TR-NEXT:    [[DOTNOT:%.*]] = icmp ugt i64 [[TMP0]], [[IDXPROM]]
-// TR-NEXT:    br i1 [[DOTNOT]], label %[[BB1:.*]], label %[[TRAP:.*]]
-// TR:       [[BB1]]:
+// TR-NEXT:    [[TMP1:%.*]] = icmp ule i64 [[TMP0]], [[IDXPROM]]
+// TR-NEXT:    [[TMP2:%.*]] = call i1 @llvm.allow.ubsan.check(i8 71), !nosanitize [[META2]]
+// TR-NEXT:    [[TMP3:%.*]] = and i1 [[TMP1]], [[TMP2]], !nosanitize [[META2]]
+// TR-NEXT:    br i1 [[TMP3]], label %[[TRAP:.*]], label %[[BB4:.*]]
+// TR:       [[BB4]]:
 // TR-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds double, ptr [[VLA]], i64 [[IDXPROM]]
-// TR-NEXT:    [[TMP2:%.*]] = load double, ptr [[ARRAYIDX]], align 8, !tbaa [[TBAA7:![0-9]+]]
-// TR-NEXT:    ret double [[TMP2]]
+// TR-NEXT:    [[TMP5:%.*]] = load double, ptr [[ARRAYIDX]], align 8, !tbaa [[TBAA7:![0-9]+]]
+// TR-NEXT:    ret double [[TMP5]]
 // TR:       [[TRAP]]:
 // TR-NEXT:    call void @llvm.ubsantrap(i8 3) #[[ATTR5]], !nosanitize [[META2]]
 // TR-NEXT:    unreachable, !nosanitize [[META2]]
@@ -208,15 +212,17 @@ void use(double*);
 // REC-NEXT:    [[VLA:%.*]] = alloca double, i64 [[TMP0]], align 16
 // REC-NEXT:    call void @use(ptr noundef nonnull [[VLA]]) #[[ATTR5:[0-9]+]]
 // REC-NEXT:    [[IDXPROM:%.*]] = sext i32 [[I]] to i64
-// REC-NEXT:    [[DOTNOT:%.*]] = icmp ugt i64 [[TMP0]], [[IDXPROM]]
-// REC-NEXT:    br i1 [[DOTNOT]], label %[[BB1:.*]], label %[[TRAP:.*]]
-// REC:       [[BB1]]:
+// REC-NEXT:    [[TMP1:%.*]] = icmp ule i64 [[TMP0]], [[IDXPROM]]
+// REC-NEXT:    [[TMP2:%.*]] = call i1 @llvm.allow.ubsan.check(i8 71), !nosanitize [[META2]]
+// REC-NEXT:    [[TMP3:%.*]] = and i1 [[TMP1]], [[TMP2]], !nosanitize [[META2]]
+// REC-NEXT:    br i1 [[TMP3]], label %[[TRAP:.*]], label %[[BB4:.*]]
+// REC:       [[BB4]]:
 // REC-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds double, ptr [[VLA]], i64 [[IDXPROM]]
-// REC-NEXT:    [[TMP2:%.*]] = load double, ptr [[ARRAYIDX]], align 8, !tbaa [[TBAA8:![0-9]+]]
-// REC-NEXT:    ret double [[TMP2]]
+// REC-NEXT:    [[TMP5:%.*]] = load double, ptr [[ARRAYIDX]], align 8, !tbaa [[TBAA8:![0-9]+]]
+// REC-NEXT:    ret double [[TMP5]]
 // REC:       [[TRAP]]:
 // REC-NEXT:    call void @__ubsan_handle_local_out_of_bounds() #[[ATTR6]], !nosanitize [[META2]]
-// REC-NEXT:    br label %[[BB1]], !nosanitize [[META2]]
+// REC-NEXT:    br label %[[BB4]], !nosanitize [[META2]]
 //
 double lbounds(int b, int i) {
   double a[b];