[llvm] [Hexagon] Don't run hexagon-loop-idiom and hexagon-vlcr passes at O0 pipeline (PR #175891)

[via llvm-commits]

https://github.com/pkarveti created https://github.com/llvm/llvm-project/pull/175891

Fixes #156787 

>From c2e5e0730e7ccf7d033fd78eb21fb0165c84be8c Mon Sep 17 00:00:00 2001
From: pavani karveti <quic_pkarveti at quicinc.com>
Date: Tue, 13 Jan 2026 15:00:17 +0530
Subject: [PATCH] [Hexagon] Don't run hexagon-loop-idiom and hexagon-vlcr
 passes at O0 pipeline

---
 llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp   |  6 ++++--
 llvm/test/CodeGen/Hexagon/print-pipeline-passes.ll | 11 +++++++++++
 2 files changed, 15 insertions(+), 2 deletions(-)
 create mode 100644 llvm/test/CodeGen/Hexagon/print-pipeline-passes.ll

diff --git a/llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp b/llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp
index d9824a3154093..3662facf07eeb 100644
--- a/llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonTargetMachine.cpp
@@ -269,11 +269,13 @@ void HexagonTargetMachine::registerPassBuilderCallbacks(PassBuilder &PB) {
 
   PB.registerLateLoopOptimizationsEPCallback(
       [=](LoopPassManager &LPM, OptimizationLevel Level) {
-        LPM.addPass(HexagonLoopIdiomRecognitionPass());
+        if (Level.getSpeedupLevel() > 0)
+          LPM.addPass(HexagonLoopIdiomRecognitionPass());
       });
   PB.registerLoopOptimizerEndEPCallback(
       [=](LoopPassManager &LPM, OptimizationLevel Level) {
-        LPM.addPass(HexagonVectorLoopCarriedReusePass());
+        if (Level.getSpeedupLevel() > 0)
+          LPM.addPass(HexagonVectorLoopCarriedReusePass());
       });
 }
 
diff --git a/llvm/test/CodeGen/Hexagon/print-pipeline-passes.ll b/llvm/test/CodeGen/Hexagon/print-pipeline-passes.ll
new file mode 100644
index 0000000000000..0f80e9c60c441
--- /dev/null
+++ b/llvm/test/CodeGen/Hexagon/print-pipeline-passes.ll
@@ -0,0 +1,11 @@
+; RUN: opt -mtriple=hexagon -S -passes='default<O0>' -print-pipeline-passes < %s 2>&1 | FileCheck --check-prefix=O0 %s
+; RUN: opt -mtriple=hexagon -S -passes='default<O2>' -print-pipeline-passes < %s 2>&1 | FileCheck %s
+
+; CHECK: hexagon-loop-idiom
+; CHECK: hexagon-vlcr
+; O0: {{^}}function(ee-instrument<>),always-inline,coro-cond(coro-early,cgscc(coro-split),coro-cleanup,globaldce),alloc-token,function(annotation-remarks),verify,print{{$}}
+
+define void @test_hexagon_passes() {
+entry:
+  ret void
+}