[LSCFG][profcheck] Add dummy branch weights for the dummy switch to dead exits #164714

mtrofin · 2025-10-22T21:38:40Z

As noted in the doc comment of handleDeadExits, the dummy switch is just an artifact of the constraints placed by the fact that we operate in a loop pass. Adding weights here is unnecessary, but the complexity is low, and it helps keep things easy for profile propagation verification (in a sense, the overall complexity would be higher if we special-cased this somehow).

Issue #147390

mtrofin · 2025-10-22T21:39:06Z

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llvmbot · 2025-10-22T21:43:47Z

@llvm/pr-subscribers-llvm-transforms

Author: Mircea Trofin (mtrofin)

Changes

As noted in the doc comment of handleDeadExits, the dummy switch is just an artifact of the constraints placed by the fact that we operate in a loop pass. Adding weights here is unnecessary, but the complexity is low, and it helps keep things easy for profile propagation verification (in a sense, the overall complexity would be higher if we special-cased this somehow).

Issue #147390

Full diff: https://github.com/llvm/llvm-project/pull/164714.diff

2 Files Affected:

(modified) llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp (+12)
(modified) llvm/test/Transforms/LoopSimplifyCFG/constant-fold-branch.ll (+54-50)

diff --git a/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp b/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
index b9546c5fa236b..e902b71776973 100644
--- a/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
@@ -24,6 +24,7 @@
 #include "llvm/Analysis/ScalarEvolution.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/ProfDataUtils.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Transforms/Scalar.h"
 #include "llvm/Transforms/Scalar/LoopPassManager.h"
@@ -393,6 +394,17 @@ class ConstantTerminatorFoldingImpl {
       DTUpdates.push_back({DominatorTree::Insert, Preheader, BB});
       ++NumLoopExitsDeleted;
     }
+    // We don't really need to add branch weights to DummySwitch, because all
+    // but one branches are just a temporary artifact - see the comment on top
+    // of this function. But, it's easy to estimate the weights, and it helps
+    // maintain a property of the overall compiler - that the branch weights
+    // don't "just get dropped" accidentally (i.e. profcheck)
+    if (DummySwitch->getParent()->getParent()->hasProfileData()) {
+      SmallVector<uint32_t> DummyBranchWeights(1 + DummySwitch->getNumCases());
+      // default. 100% probability, the rest are dead.
+      DummyBranchWeights[0] = 1;
+      setBranchWeights(*DummySwitch, DummyBranchWeights, /*IsExpected=*/false);
+    }
 
     assert(L.getLoopPreheader() == NewPreheader && "Malformed CFG?");
     if (Loop *OuterLoop = LI.getLoopFor(Preheader)) {
diff --git a/llvm/test/Transforms/LoopSimplifyCFG/constant-fold-branch.ll b/llvm/test/Transforms/LoopSimplifyCFG/constant-fold-branch.ll
index 1ec212f0bb5ea..46b6209986fed 100644
--- a/llvm/test/Transforms/LoopSimplifyCFG/constant-fold-branch.ll
+++ b/llvm/test/Transforms/LoopSimplifyCFG/constant-fold-branch.ll
@@ -1,4 +1,4 @@
-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals
 ; REQUIRES: asserts
 ; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -passes=loop-simplifycfg -verify-loop-info -verify-dom-info -verify-loop-lcssa < %s | FileCheck %s
 ; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -passes='require<domtree>,loop(loop-simplifycfg)' -verify-loop-info -verify-dom-info -verify-loop-lcssa < %s | FileCheck %s
@@ -59,7 +59,7 @@ define i32 @dead_backedge_test_switch_loop(i32 %end) {
 ; CHECK:       dead_backedge:
 ; CHECK-NEXT:    [[I_2]] = add i32 [[I_1]], 10
 ; CHECK-NEXT:    switch i32 1, label [[EXIT:%.*]] [
-; CHECK-NEXT:    i32 0, label [[HEADER_BACKEDGE]]
+; CHECK-NEXT:      i32 0, label [[HEADER_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       exit:
 ; CHECK-NEXT:    [[I_2_LCSSA:%.*]] = phi i32 [ [[I_2]], [[DEAD_BACKEDGE]] ]
@@ -233,12 +233,12 @@ exit:
 
 ; Check that we preserve static reachibility of a dead exit block while deleting
 ; a branch.
-define i32 @dead_exit_test_branch_loop(i32 %end) {
+define i32 @dead_exit_test_branch_loop(i32 %end) !prof !{!"function_entry_count", i32 10} {
 ; CHECK-LABEL: @dead_exit_test_branch_loop(
 ; CHECK-NEXT:  preheader:
 ; CHECK-NEXT:    switch i32 0, label [[PREHEADER_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[DEAD:%.*]]
-; CHECK-NEXT:    ]
+; CHECK-NEXT:      i32 1, label [[DEAD:%.*]]
+; CHECK-NEXT:    ], !prof [[PROF1:![0-9]+]]
 ; CHECK:       preheader.split:
 ; CHECK-NEXT:    br label [[HEADER:%.*]]
 ; CHECK:       header:
@@ -262,7 +262,7 @@ preheader:
 
 header:
   %i = phi i32 [0, %preheader], [%i.inc, %backedge]
-  br i1 true, label %backedge, label %dead
+  br i1 true, label %backedge, label %dead, !prof !{!"branch_weights", i32 10, i32 1}
 
 dead:
   br label %dummy
@@ -286,7 +286,7 @@ define i32 @dead_exit_test_switch_loop(i32 %end) {
 ; CHECK-LABEL: @dead_exit_test_switch_loop(
 ; CHECK-NEXT:  preheader:
 ; CHECK-NEXT:    switch i32 0, label [[PREHEADER_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[DEAD:%.*]]
+; CHECK-NEXT:      i32 1, label [[DEAD:%.*]]
 ; CHECK-NEXT:    ]
 ; CHECK:       preheader.split:
 ; CHECK-NEXT:    br label [[HEADER:%.*]]
@@ -383,9 +383,9 @@ define i32 @dead_loop_test_switch_loop(i32 %end) {
 ; CHECK:       header:
 ; CHECK-NEXT:    [[I:%.*]] = phi i32 [ 0, [[PREHEADER:%.*]] ], [ [[I_INC:%.*]], [[BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    switch i32 1, label [[DEAD:%.*]] [
-; CHECK-NEXT:    i32 0, label [[DEAD]]
-; CHECK-NEXT:    i32 1, label [[BACKEDGE]]
-; CHECK-NEXT:    i32 2, label [[DEAD]]
+; CHECK-NEXT:      i32 0, label [[DEAD]]
+; CHECK-NEXT:      i32 1, label [[BACKEDGE]]
+; CHECK-NEXT:      i32 2, label [[DEAD]]
 ; CHECK-NEXT:    ]
 ; CHECK:       dead:
 ; CHECK-NEXT:    [[I_2:%.*]] = add i32 [[I]], 1
@@ -552,7 +552,7 @@ define i32 @inf_loop_test_branch_loop(i32 %end) {
 ; CHECK-LABEL: @inf_loop_test_branch_loop(
 ; CHECK-NEXT:  preheader:
 ; CHECK-NEXT:    switch i32 0, label [[PREHEADER_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[EXIT:%.*]]
+; CHECK-NEXT:      i32 1, label [[EXIT:%.*]]
 ; CHECK-NEXT:    ]
 ; CHECK:       preheader.split:
 ; CHECK-NEXT:    br label [[HEADER:%.*]]
@@ -592,7 +592,7 @@ define i32 @inf_loop_test_switch_loop(i32 %end) {
 ; CHECK-LABEL: @inf_loop_test_switch_loop(
 ; CHECK-NEXT:  preheader:
 ; CHECK-NEXT:    switch i32 0, label [[PREHEADER_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[EXIT:%.*]]
+; CHECK-NEXT:      i32 1, label [[EXIT:%.*]]
 ; CHECK-NEXT:    ]
 ; CHECK:       preheader.split:
 ; CHECK-NEXT:    br label [[HEADER:%.*]]
@@ -1001,7 +1001,7 @@ define i32 @full_sub_loop_test_switch_loop(i32 %end) {
 ; CHECK-NEXT:    [[I:%.*]] = phi i32 [ 0, [[OUTER_HEADER]] ], [ [[I_INC:%.*]], [[BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    [[MUL:%.*]] = mul i32 [[I]], [[I]]
 ; CHECK-NEXT:    switch i32 1, label [[DEAD:%.*]] [
-; CHECK-NEXT:    i32 0, label [[BACKEDGE]]
+; CHECK-NEXT:      i32 0, label [[BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       dead:
 ; CHECK-NEXT:    [[I_2:%.*]] = add i32 [[I]], 1
@@ -1010,7 +1010,7 @@ define i32 @full_sub_loop_test_switch_loop(i32 %end) {
 ; CHECK-NEXT:    [[I_1:%.*]] = phi i32 [ [[I]], [[HEADER]] ], [ [[I_2]], [[DEAD]] ]
 ; CHECK-NEXT:    [[I_INC]] = add i32 [[I_1]], 1
 ; CHECK-NEXT:    switch i32 1, label [[OUTER_BACKEDGE]] [
-; CHECK-NEXT:    i32 0, label [[HEADER]]
+; CHECK-NEXT:      i32 0, label [[HEADER]]
 ; CHECK-NEXT:    ]
 ; CHECK:       outer_backedge:
 ; CHECK-NEXT:    [[I_INC_LCSSA:%.*]] = phi i32 [ [[I_INC]], [[BACKEDGE]] ]
@@ -1132,7 +1132,7 @@ define i32 @full_sub_loop_test_switch_loop_inverse_1(i32 %end) {
 ; CHECK-NEXT:    [[I:%.*]] = phi i32 [ 0, [[OUTER_HEADER]] ], [ [[I_INC:%.*]], [[BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    [[MUL:%.*]] = mul i32 [[I]], [[I]]
 ; CHECK-NEXT:    switch i32 1, label [[BACKEDGE]] [
-; CHECK-NEXT:    i32 0, label [[DEAD:%.*]]
+; CHECK-NEXT:      i32 0, label [[DEAD:%.*]]
 ; CHECK-NEXT:    ]
 ; CHECK:       dead:
 ; CHECK-NEXT:    [[I_2:%.*]] = add i32 [[I]], 1
@@ -1141,7 +1141,7 @@ define i32 @full_sub_loop_test_switch_loop_inverse_1(i32 %end) {
 ; CHECK-NEXT:    [[I_1:%.*]] = phi i32 [ [[I]], [[HEADER]] ], [ [[I_2]], [[DEAD]] ]
 ; CHECK-NEXT:    [[I_INC]] = add i32 [[I_1]], 1
 ; CHECK-NEXT:    switch i32 1, label [[OUTER_BACKEDGE]] [
-; CHECK-NEXT:    i32 0, label [[HEADER]]
+; CHECK-NEXT:      i32 0, label [[HEADER]]
 ; CHECK-NEXT:    ]
 ; CHECK:       outer_backedge:
 ; CHECK-NEXT:    [[I_INC_LCSSA:%.*]] = phi i32 [ [[I_INC]], [[BACKEDGE]] ]
@@ -1195,7 +1195,7 @@ define i32 @full_sub_loop_test_branch_loop_inverse_2(i32 %end) {
 ; CHECK:       outer_header:
 ; CHECK-NEXT:    [[J:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[J_INC:%.*]], [[OUTER_BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    switch i32 0, label [[PREHEADER_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[OUTER_BACKEDGE]]
+; CHECK-NEXT:      i32 1, label [[OUTER_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       preheader.split:
 ; CHECK-NEXT:    br label [[HEADER:%.*]]
@@ -1256,7 +1256,7 @@ define i32 @full_sub_loop_test_switch_loop_inverse_2(i32 %end) {
 ; CHECK:       outer_header:
 ; CHECK-NEXT:    [[J:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[J_INC:%.*]], [[OUTER_BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    switch i32 0, label [[PREHEADER_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[OUTER_BACKEDGE]]
+; CHECK-NEXT:      i32 1, label [[OUTER_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       preheader.split:
 ; CHECK-NEXT:    br label [[HEADER:%.*]]
@@ -1318,7 +1318,7 @@ define i32 @full_sub_loop_test_branch_loop_inverse_3(i32 %end) {
 ; CHECK:       outer_header:
 ; CHECK-NEXT:    [[J:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[J_INC:%.*]], [[OUTER_BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    switch i32 0, label [[PREHEADER_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[OUTER_BACKEDGE]]
+; CHECK-NEXT:      i32 1, label [[OUTER_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       preheader.split:
 ; CHECK-NEXT:    br label [[HEADER:%.*]]
@@ -1378,7 +1378,7 @@ define i32 @full_sub_loop_test_switch_loop_inverse_3(i32 %end) {
 ; CHECK:       outer_header:
 ; CHECK-NEXT:    [[J:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[J_INC:%.*]], [[OUTER_BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    switch i32 0, label [[PREHEADER_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[OUTER_BACKEDGE]]
+; CHECK-NEXT:      i32 1, label [[OUTER_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       preheader.split:
 ; CHECK-NEXT:    br label [[HEADER:%.*]]
@@ -1441,7 +1441,7 @@ define i32 @exit_branch_from_inner_to_grandparent(i1 %cond1, i1 %cond2, i32 %N)
 ; CHECK:       loop_2:
 ; CHECK-NEXT:    [[J:%.*]] = phi i32 [ 0, [[LOOP_1]] ], [ [[J_NEXT:%.*]], [[LOOP_2_BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    switch i32 0, label [[LOOP_2_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[LOOP_2_BACKEDGE]]
+; CHECK-NEXT:      i32 1, label [[LOOP_2_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       loop_2.split:
 ; CHECK-NEXT:    br label [[LOOP_3:%.*]]
@@ -1510,7 +1510,7 @@ define i32 @exit_switch_from_inner_to_grandparent(i1 %cond1, i1 %cond2, i32 %N)
 ; CHECK:       loop_2:
 ; CHECK-NEXT:    [[J:%.*]] = phi i32 [ 0, [[LOOP_1]] ], [ [[J_NEXT:%.*]], [[LOOP_2_BACKEDGE:%.*]] ]
 ; CHECK-NEXT:    switch i32 0, label [[LOOP_2_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[LOOP_2_BACKEDGE]]
+; CHECK-NEXT:      i32 1, label [[LOOP_2_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       loop_2.split:
 ; CHECK-NEXT:    br label [[LOOP_3:%.*]]
@@ -1654,7 +1654,7 @@ define i32 @intermediate_switch_from_inner_to_grandparent(i1 %cond1, i1 %cond2,
 ; CHECK-NEXT:    br i1 [[COND1:%.*]], label [[LOOP_3_BACKEDGE]], label [[INTERMEDIATE:%.*]]
 ; CHECK:       intermediate:
 ; CHECK-NEXT:    switch i32 1, label [[LOOP_1_BACKEDGE_LOOPEXIT:%.*]] [
-; CHECK-NEXT:    i32 0, label [[LOOP_3_BACKEDGE]]
+; CHECK-NEXT:      i32 0, label [[LOOP_3_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       loop_3_backedge:
 ; CHECK-NEXT:    [[K_NEXT]] = add i32 [[K]], 1
@@ -1792,7 +1792,7 @@ define i32 @intermediate_switch_from_inner_to_parent(i1 %cond1, i1 %cond2, i32 %
 ; CHECK-NEXT:    br i1 [[COND1:%.*]], label [[LOOP_3_BACKEDGE]], label [[INTERMEDIATE:%.*]]
 ; CHECK:       intermediate:
 ; CHECK-NEXT:    switch i32 1, label [[LOOP_2_BACKEDGE]] [
-; CHECK-NEXT:    i32 0, label [[LOOP_3_BACKEDGE]]
+; CHECK-NEXT:      i32 0, label [[LOOP_3_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       loop_3_backedge:
 ; CHECK-NEXT:    [[K_NEXT]] = add i32 [[K]], 1
@@ -1944,7 +1944,7 @@ define i32 @intermediate_subloop_switch_from_inner_to_grandparent(i1 %cond1, i1
 ; CHECK-NEXT:    br i1 [[COND3:%.*]], label [[INTERMEDIATE_LOOP]], label [[INTERMEDIATE_EXIT:%.*]]
 ; CHECK:       intermediate_exit:
 ; CHECK-NEXT:    switch i32 1, label [[LOOP_1_BACKEDGE_LOOPEXIT:%.*]] [
-; CHECK-NEXT:    i32 0, label [[LOOP_3_BACKEDGE]]
+; CHECK-NEXT:      i32 0, label [[LOOP_3_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       loop_3_backedge:
 ; CHECK-NEXT:    [[K_NEXT]] = add i32 [[K]], 1
@@ -2102,7 +2102,7 @@ define i32 @intermediate_subloop_switch_from_inner_to_parent(i1 %cond1, i1 %cond
 ; CHECK-NEXT:    br i1 [[COND3:%.*]], label [[INTERMEDIATE_LOOP]], label [[INTERMEDIATE_EXIT:%.*]]
 ; CHECK:       intermediate_exit:
 ; CHECK-NEXT:    switch i32 1, label [[LOOP_2_BACKEDGE]] [
-; CHECK-NEXT:    i32 0, label [[LOOP_3_BACKEDGE]]
+; CHECK-NEXT:      i32 0, label [[LOOP_3_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       loop_3_backedge:
 ; CHECK-NEXT:    [[K_NEXT]] = add i32 [[K]], 1
@@ -2267,7 +2267,7 @@ define i32 @intermediate_complex_subloop_switch_from_inner_to_parent(i1 %cond1,
 ; CHECK-NEXT:    br i1 [[COND2:%.*]], label [[INTERMEDIATE_LOOP_BACKEDGE]], label [[INTERMEDIATE_EXIT:%.*]]
 ; CHECK:       intermediate_exit:
 ; CHECK-NEXT:    switch i32 1, label [[LOOP_2_BACKEDGE]] [
-; CHECK-NEXT:    i32 0, label [[LOOP_3_BACKEDGE]]
+; CHECK-NEXT:      i32 0, label [[LOOP_3_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       loop_3_backedge:
 ; CHECK-NEXT:    [[K_NEXT]] = add i32 [[K]], 1
@@ -2440,7 +2440,7 @@ define i32 @intermediate_complex_subloop_switch_from_inner_to_grandparent(i1 %co
 ; CHECK-NEXT:    br i1 [[COND2:%.*]], label [[INTERMEDIATE_LOOP_BACKEDGE]], label [[INTERMEDIATE_EXIT:%.*]]
 ; CHECK:       intermediate_exit:
 ; CHECK-NEXT:    switch i32 1, label [[LOOP_1_BACKEDGE_LOOPEXIT:%.*]] [
-; CHECK-NEXT:    i32 0, label [[LOOP_3_BACKEDGE]]
+; CHECK-NEXT:      i32 0, label [[LOOP_3_BACKEDGE]]
 ; CHECK-NEXT:    ]
 ; CHECK:       loop_3_backedge:
 ; CHECK-NEXT:    [[K_NEXT]] = add i32 [[K]], 1
@@ -2585,38 +2585,38 @@ define void @test_crash_01(i1 %arg, i32 %arg2) {
 ; CHECK-NEXT:  bb:
 ; CHECK-NEXT:    br label [[BB1:%.*]]
 ; CHECK:       bb1:
-; CHECK-NEXT:    br i1 %arg, label [[BB17:%.*]], label [[BB2:%.*]]
+; CHECK-NEXT:    br i1 [[ARG:%.*]], label [[BB17:%.*]], label [[BB2:%.*]]
 ; CHECK:       bb2:
 ; CHECK-NEXT:    switch i32 0, label [[BB2_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[BB19:%.*]]
+; CHECK-NEXT:      i32 1, label [[BB19:%.*]]
 ; CHECK-NEXT:    ]
 ; CHECK:       bb2.split:
 ; CHECK-NEXT:    br label [[BB3:%.*]]
 ; CHECK:       bb3:
-; CHECK-NEXT:    switch i32 %arg2, label [[BB16:%.*]] [
-; CHECK-NEXT:    i32 0, label [[BB15:%.*]]
-; CHECK-NEXT:    i32 1, label [[BB14:%.*]]
-; CHECK-NEXT:    i32 2, label [[BB13:%.*]]
-; CHECK-NEXT:    i32 3, label [[BB12:%.*]]
-; CHECK-NEXT:    i32 4, label [[BB11:%.*]]
-; CHECK-NEXT:    i32 5, label [[BB8:%.*]]
-; CHECK-NEXT:    i32 6, label [[BB10:%.*]]
-; CHECK-NEXT:    i32 7, label [[BB9:%.*]]
-; CHECK-NEXT:    i32 8, label [[BB7:%.*]]
+; CHECK-NEXT:    switch i32 [[ARG2:%.*]], label [[BB16:%.*]] [
+; CHECK-NEXT:      i32 0, label [[BB15:%.*]]
+; CHECK-NEXT:      i32 1, label [[BB14:%.*]]
+; CHECK-NEXT:      i32 2, label [[BB13:%.*]]
+; CHECK-NEXT:      i32 3, label [[BB12:%.*]]
+; CHECK-NEXT:      i32 4, label [[BB11:%.*]]
+; CHECK-NEXT:      i32 5, label [[BB8:%.*]]
+; CHECK-NEXT:      i32 6, label [[BB10:%.*]]
+; CHECK-NEXT:      i32 7, label [[BB9:%.*]]
+; CHECK-NEXT:      i32 8, label [[BB7:%.*]]
 ; CHECK-NEXT:    ]
 ; CHECK:       bb7:
 ; CHECK-NEXT:    unreachable
 ; CHECK:       bb8:
-; CHECK-NEXT:    switch i32 %arg2, label [[BB28:%.*]] [
-; CHECK-NEXT:    i32 0, label [[BB27:%.*]]
-; CHECK-NEXT:    i32 1, label [[BB26:%.*]]
-; CHECK-NEXT:    i32 2, label [[BB23:%.*]]
-; CHECK-NEXT:    i32 3, label [[BB24:%.*]]
-; CHECK-NEXT:    i32 4, label [[BB25:%.*]]
-; CHECK-NEXT:    i32 5, label [[BB29:%.*]]
-; CHECK-NEXT:    i32 6, label [[BB22:%.*]]
-; CHECK-NEXT:    i32 7, label [[BB20:%.*]]
-; CHECK-NEXT:    i32 8, label [[BB21:%.*]]
+; CHECK-NEXT:    switch i32 [[ARG2]], label [[BB28:%.*]] [
+; CHECK-NEXT:      i32 0, label [[BB27:%.*]]
+; CHECK-NEXT:      i32 1, label [[BB26:%.*]]
+; CHECK-NEXT:      i32 2, label [[BB23:%.*]]
+; CHECK-NEXT:      i32 3, label [[BB24:%.*]]
+; CHECK-NEXT:      i32 4, label [[BB25:%.*]]
+; CHECK-NEXT:      i32 5, label [[BB29:%.*]]
+; CHECK-NEXT:      i32 6, label [[BB22:%.*]]
+; CHECK-NEXT:      i32 7, label [[BB20:%.*]]
+; CHECK-NEXT:      i32 8, label [[BB21:%.*]]
 ; CHECK-NEXT:    ]
 ; CHECK:       bb9:
 ; CHECK-NEXT:    unreachable
@@ -2772,3 +2772,7 @@ bb28:                                             ; preds = %bb8
 bb29:                                             ; preds = %bb8
   br label %bb6
 }
+;.
+; CHECK: [[META0:![0-9]+]] = !{!"function_entry_count", i32 10}
+; CHECK: [[PROF1]] = !{!"branch_weights", i32 1, i32 0}
+;.

jinhuang1102

LGTM

…ead exits

mtrofin · 2025-11-06T01:13:06Z

Merge activity

Nov 6, 1:13 AM UTC: A user started a stack merge that includes this pull request via Graphite.
Nov 6, 1:14 AM UTC: @mtrofin merged this pull request with Graphite.

mtrofin mentioned this pull request Oct 22, 2025

[LIR][profcheck] Reuse the loop's exit condition profile #164523

Merged

mtrofin marked this pull request as ready for review October 22, 2025 21:43

llvmbot added the llvm:transforms label Oct 22, 2025

mtrofin requested review from alanzhao1 and jinhuang1102 October 22, 2025 21:43

mtrofin requested a review from xortator October 22, 2025 21:46

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mtrofin mentioned this pull request Nov 4, 2025

[NFC][SLU] Update SimpleLoopUnswitch/guards.ll #166285

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Base automatically changed from users/mtrofin/10-21-_lir_profcheck_reuse_the_loop_s_exit_condition_profile to main November 5, 2025 21:39

[LSCFG][profcheck] Add dummy branch weights for the dummy switch to d…

4414d97

…ead exits

mtrofin force-pushed the users/mtrofin/10-22-_lscfg_profcheck_add_dummy_branch_weights_for_the_dummy_switch_to_dead_exits branch from eb82bc3 to 4414d97 Compare November 5, 2025 21:41

mtrofin merged commit 77e3975 into main Nov 6, 2025
8 of 9 checks passed

mtrofin deleted the users/mtrofin/10-22-_lscfg_profcheck_add_dummy_branch_weights_for_the_dummy_switch_to_dead_exits branch November 6, 2025 01:14

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[LSCFG][profcheck] Add dummy branch weights for the dummy switch to dead exits #164714

[LSCFG][profcheck] Add dummy branch weights for the dummy switch to dead exits #164714

mtrofin commented Oct 22, 2025 •

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[LSCFG][profcheck] Add dummy branch weights for the dummy switch to dead exits #164714

[LSCFG][profcheck] Add dummy branch weights for the dummy switch to dead exits #164714

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mtrofin commented Oct 22, 2025 •

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