https://github.com/mtrofin updated https://github.com/llvm/llvm-project/pull/164271
>From e7d4aa95ce5417d232769b564863abb47bbf42dc Mon Sep 17 00:00:00 2001 From: Mircea Trofin <[email protected]> Date: Mon, 20 Oct 2025 08:21:26 -0700 Subject: [PATCH] [SLU][profcheck] create likely branch weights for guard->branch --- llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp | 12 +++++++++--- llvm/test/Transforms/SimpleLoopUnswitch/guards.ll | 10 ++++++++-- 2 files changed, 17 insertions(+), 5 deletions(-) diff --git a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp index 239526e85e1fd..86b2090081ed0 100644 --- a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp +++ b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp @@ -40,6 +40,7 @@ #include "llvm/IR/Instruction.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/IntrinsicInst.h" +#include "llvm/IR/MDBuilder.h" #include "llvm/IR/Module.h" #include "llvm/IR/PatternMatch.h" #include "llvm/IR/ProfDataUtils.h" @@ -2831,9 +2832,14 @@ static BranchInst *turnGuardIntoBranch(IntrinsicInst *GI, Loop &L, MSSAU->getMemorySSA()->verifyMemorySSA(); DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Eager); - Instruction *DeoptBlockTerm = - SplitBlockAndInsertIfThen(GI->getArgOperand(0), GI, true, - GI->getMetadata(LLVMContext::MD_prof), &DTU, &LI); + // llvm.experimental.guard doesn't have branch weights. We can assume, + // however, that the deopt path is unlikely. + Instruction *DeoptBlockTerm = SplitBlockAndInsertIfThen( + GI->getArgOperand(0), GI, true, + !ProfcheckDisableMetadataFixes && EstimateProfile + ? MDBuilder(GI->getContext()).createUnlikelyBranchWeights() + : nullptr, + &DTU, &LI); BranchInst *CheckBI = cast<BranchInst>(CheckBB->getTerminator()); // SplitBlockAndInsertIfThen inserts control flow that branches to // DeoptBlockTerm if the condition is true. We want the opposite. diff --git a/llvm/test/Transforms/SimpleLoopUnswitch/guards.ll b/llvm/test/Transforms/SimpleLoopUnswitch/guards.ll index da4f4cc80d96f..812a183673bcc 100644 --- a/llvm/test/Transforms/SimpleLoopUnswitch/guards.ll +++ b/llvm/test/Transforms/SimpleLoopUnswitch/guards.ll @@ -1,4 +1,4 @@ -; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: -p --version 5 +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: -p --check-globals all --version 5 ; RUN: opt -passes='loop(simple-loop-unswitch<nontrivial>),verify<loops>' -simple-loop-unswitch-guards -S < %s | FileCheck %s ; RUN: opt -passes='simple-loop-unswitch<nontrivial>' -simple-loop-unswitch-guards -S < %s | FileCheck %s ; RUN: opt -passes='loop-mssa(simple-loop-unswitch<nontrivial>),verify<loops>' -simple-loop-unswitch-guards -verify-memoryssa -verify-loop-info -S < %s | FileCheck %s @@ -167,7 +167,7 @@ exit: define void @test_nested_loop(i1 %cond, i32 %N, i1 %arg) { ; CHECK-LABEL: define void @test_nested_loop(i1 %cond, i32 %N, i1 %arg) { ; CHECK-NEXT: entry: -; CHECK-NEXT: br i1 %cond, label %entry.split, label %outer_loop.split +; CHECK-NEXT: br i1 %cond, label %entry.split, label %outer_loop.split, !prof !1 ; CHECK: entry.split: ; CHECK-NEXT: br i1 %arg, label %entry.split.split.us, label %entry.split.split ; CHECK: entry.split.split.us: @@ -337,3 +337,9 @@ exit: declare void @may_throw(i32 %i) declare i32 @__CxxFrameHandler3(...) + +!0 = !{!"function_entry_count", i32 10} +;. +; CHECK: !0 = !{!"function_entry_count", i32 10} +; CHECK: !1 = !{!"branch_weights", i32 1048575, i32 1} +;. _______________________________________________ llvm-branch-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
