[llvm] efdbf7b - [Hexagon] Use trap0(#0xDB) for debugtrap instead of brkpt (#189446)

[via llvm-commits]

Author: Brian Cain
Date: 2026-04-03T15:12:49-05:00
New Revision: efdbf7b815b7c8fa161819e87050154d62b3d146

URL: https://github.com/llvm/llvm-project/commit/efdbf7b815b7c8fa161819e87050154d62b3d146
DIFF: https://github.com/llvm/llvm-project/commit/efdbf7b815b7c8fa161819e87050154d62b3d146.diff

LOG: [Hexagon] Use trap0(#0xDB) for debugtrap instead of brkpt (#189446)

The brkpt instruction is intended for the in-silicon debugger (ISDB).
When ISDB is not enabled, brkpt is treated as a NOP, so
__builtin_debugtrap() would silently do nothing in user-mode Linux
processes.

Use trap0(#0xDB) instead.

Added: 
    

Modified: 
    llvm/lib/Target/Hexagon/HexagonPatterns.td
    llvm/test/CodeGen/Hexagon/trap-crash.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/Hexagon/HexagonPatterns.td b/llvm/lib/Target/Hexagon/HexagonPatterns.td
index 3f836e8c1dbef..0c9650585b613 100644
--- a/llvm/lib/Target/Hexagon/HexagonPatterns.td
+++ b/llvm/lib/Target/Hexagon/HexagonPatterns.td
@@ -3461,7 +3461,7 @@ def HexagonBARRIER: SDNode<"HexagonISD::BARRIER", SDTNone, [SDNPHasChain]>;
 def: Pat<(HexagonBARRIER), (Y2_barrier)>;
 
 def: Pat<(trap), (PS_crash)>;
-def: Pat<(debugtrap), (Y2_break)>;
+def: Pat<(debugtrap), (J2_trap0 0xDB)>;
 
 // Read cycle counter.
 def : Pat<(i64 (readcyclecounter)), (PS_readcr64 UPCYCLE)>;

diff  --git a/llvm/test/CodeGen/Hexagon/trap-crash.ll b/llvm/test/CodeGen/Hexagon/trap-crash.ll
index c19f90c297abb..7ff3db1e75c40 100644
--- a/llvm/test/CodeGen/Hexagon/trap-crash.ll
+++ b/llvm/test/CodeGen/Hexagon/trap-crash.ll
@@ -14,7 +14,7 @@ entry:
 }
 
 ; CHECK-LABEL: f1
-; CHECK: brkpt
+; CHECK: trap0(#219)
 define i32 @f1() noreturn nounwind {
 entry:
   tail call void @llvm.debugtrap()