[clang] 55857e1 - CodeGen: Switch to generating llvm.looptrap instead of llvm.cond.loop.

[via cfe-commits]

Author: Peter Collingbourne
Date: 2026-02-13T14:15:17-08:00
New Revision: 55857e14bc2261305db70dbe1f0e3af93c229aad

URL: https://github.com/llvm/llvm-project/commit/55857e14bc2261305db70dbe1f0e3af93c229aad
DIFF: https://github.com/llvm/llvm-project/commit/55857e14bc2261305db70dbe1f0e3af93c229aad.diff

LOG: CodeGen: Switch to generating llvm.looptrap instead of llvm.cond.loop.



Reviewers: fmayer, vitalybuka

Reviewed By: fmayer

Pull Request: https://github.com/llvm/llvm-project/pull/181300

Added: 
    

Modified: 
    clang/lib/CodeGen/CGExpr.cpp
    clang/test/CodeGenCXX/sanitize-trap-loop.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index 8de1c53b1b213..a0a1a5675654c 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -4438,12 +4438,6 @@ void CodeGenFunction::EmitUnreachable(SourceLocation Loc) {
 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked,
                                     SanitizerHandler CheckHandlerID,
                                     bool NoMerge, const TrapReason *TR) {
-  if (CGM.getCodeGenOpts().SanitizeTrapLoop) {
-    Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::cond_loop),
-                       Builder.CreateNot(Checked));
-    return;
-  }
-
   llvm::BasicBlock *Cont = createBasicBlock("cont");
 
   // If we're optimizing, collapse all calls to trap down to just one per
@@ -4495,9 +4489,14 @@ void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked,
 
     ApplyDebugLocation applyTrapDI(*this, TrapLocation);
 
-    llvm::CallInst *TrapCall =
-        Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::ubsantrap),
-                           llvm::ConstantInt::get(CGM.Int8Ty, CheckHandlerID));
+    llvm::CallInst *TrapCall;
+    if (CGM.getCodeGenOpts().SanitizeTrapLoop)
+      TrapCall =
+          Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::looptrap));
+    else
+      TrapCall = Builder.CreateCall(
+          CGM.getIntrinsic(llvm::Intrinsic::ubsantrap),
+          llvm::ConstantInt::get(CGM.Int8Ty, CheckHandlerID));
 
     if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
       auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",

diff  --git a/clang/test/CodeGenCXX/sanitize-trap-loop.cpp b/clang/test/CodeGenCXX/sanitize-trap-loop.cpp
index ee083c52f5c30..3c7af1af907c0 100644
--- a/clang/test/CodeGenCXX/sanitize-trap-loop.cpp
+++ b/clang/test/CodeGenCXX/sanitize-trap-loop.cpp
@@ -6,15 +6,17 @@ struct A {
 
 void vcall(A *a) {
   // CHECK: [[TEST:%.*]] = call i1 @llvm.type.test
-  // CHECK-NEXT: [[NOT:%.*]] = xor i1 [[TEST]], true
-  // CHECK-NEXT: call void @llvm.cond.loop(i1 [[NOT]])
+  // CHECK-NEXT: br i1 [[TEST]], label %cont, label %trap
+  // CHECK: trap:
+  // CHECK-NEXT: call void @llvm.looptrap()
   a->f();
 }
 
 int overflow(int a, int b) {
   // CHECK: [[OVERFLOW:%.*]] = extractvalue { i32, i1 } %2, 1, !nosanitize
   // CHECK-NEXT: [[NOTOVERFLOW:%.*]] = xor i1 [[OVERFLOW]], true, !nosanitize
-  // CHECK-NEXT: [[NOTNOTOVERFLOW:%.*]] = xor i1 [[NOTOVERFLOW]], true, !nosanitize
-  // CHECK-NEXT: call void @llvm.cond.loop(i1 [[NOTNOTOVERFLOW]])
+  // CHECK-NEXT: br i1 [[NOTOVERFLOW]], label %cont, label %trap
+  // CHECK: trap:
+  // CHECK-NEXT: call void @llvm.looptrap()
   return a + b;
 }