[JumpThreading] Fix jump threading to remove pointers to deleted basi…

…c blocks that contain Tapir instructions.
OpenCilk · Oct 19, 2023 · 6876173 · 6876173
1 parent 3dd78f6
commit 6876173
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Showing 3 changed files with 32 additions and 1 deletion.
diff --git a/llvm/include/llvm/Transforms/Scalar/JumpThreading.h b/llvm/include/llvm/Transforms/Scalar/JumpThreading.h
@@ -89,7 +89,8 @@ class JumpThreadingPass : public PassInfoMixin<JumpThreadingPass> {
 #else
   SmallSet<AssertingVH<const BasicBlock>, 16> LoopHeaders;
 #endif
-  DenseMap<const BasicBlock *, SmallPtrSet<const BasicBlock *, 16>> TapirTasks;
+  DenseMap<AssertingVH<const BasicBlock>, SmallPtrSet<const BasicBlock *, 16>>
+      TapirTasks;
 
   unsigned BBDupThreshold;
   unsigned DefaultBBDupThreshold;

diff --git a/llvm/lib/Transforms/Scalar/JumpThreading.cpp b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
@@ -451,6 +451,7 @@ bool JumpThreadingPass::runImpl(Function &F, TargetLibraryInfo *TLI_,
                           << '\n');
         LoopHeaders.erase(&BB);
         LVI->eraseBlock(&BB);
+        TapirTasks.erase(&BB);
         DeleteDeadBlock(&BB, DTU);
         Changed = true;
         continue;
@@ -480,6 +481,7 @@ bool JumpThreadingPass::runImpl(Function &F, TargetLibraryInfo *TLI_,
   } while (Changed);
 
   LoopHeaders.clear();
+  TapirTasks.clear();
   return EverChanged;
 }
 

diff --git a/llvm/test/Transforms/Tapir/jump-threading-tapir-vh.ll b/llvm/test/Transforms/Tapir/jump-threading-tapir-vh.ll
@@ -0,0 +1,28 @@
+; Check that jump threading releases value handles to basic blocks
+; containing Tapir instructions.
+;
+; RUN: opt < %s -passes="cgscc(devirt<4>(function<eager-inv>(jump-threading,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;no-hoist-common-insts;no-sink-common-insts>)))" -S | FileCheck %s
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define linkonce_odr void @_ZN4gbbs8nn_chain3HACINS_10MinLinkageINS_15symmetric_graphINS_16symmetric_vertexEjEENS_20SimilarityClusteringENS_12ActualWeightEEES4_jEEDaRNS3_IT0_T1_EERT_() personality ptr null {
+entry:
+  unreachable
+
+pfor.body.entry.i.i.i:                            ; preds = %pfor.inc.i.i.i
+  reattach within none, label %pfor.inc.i.i.i
+
+pfor.inc.i.i.i:                                   ; preds = %pfor.inc.i.i.i, %pfor.body.entry.i.i.i
+  detach within none, label %pfor.body.entry.i.i.i, label %pfor.inc.i.i.i
+}
+
+; CHECK: define linkonce_odr void @_ZN4gbbs8nn_chain3HACINS_10MinLinkageINS_15symmetric_graphINS_16symmetric_vertexEjEENS_20SimilarityClusteringENS_12ActualWeightEEES4_jEEDaRNS3_IT0_T1_EERT_()
+; CHECK: entry:
+; CHECK-NEXT: unreachable
+; CHECK-NOT: pfor.body.entry.i.i.i:
+; CHECK-NOT: reattach
+; CHECK-NOT: pfor.inc.i.i.i:
+; CHECK-NOT: detach
+
+; uselistorder directives
+uselistorder ptr null, { 1, 2, 0 }