From 16717a7c562d05915c1b30792eef24de5b264cc6 Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Fri, 3 Feb 2012 01:07:01 +0000 Subject: [PATCH] Fix SSAUpdaterImpl's RecordMatchingPHI to record exactly the PHI nodes which were matched, rather than climbing up the original PHI node's operands to rediscover PHI nodes for recording, since the PHI nodes found that are not necessarily part of the matched set. This fixes rdar://10589171. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149654 91177308-0d34-0410-b5e6-96231b3b80d8 --- .../llvm/Transforms/Utils/SSAUpdaterImpl.h | 43 +++-------- test/Transforms/ScalarRepl/phi-cycle.ll | 77 +++++++++++++++++++ 2 files changed, 88 insertions(+), 32 deletions(-) create mode 100644 test/Transforms/ScalarRepl/phi-cycle.ll diff --git a/include/llvm/Transforms/Utils/SSAUpdaterImpl.h b/include/llvm/Transforms/Utils/SSAUpdaterImpl.h index 15d65bcf8c6..a9adbd73c15 100644 --- a/include/llvm/Transforms/Utils/SSAUpdaterImpl.h +++ b/include/llvm/Transforms/Utils/SSAUpdaterImpl.h @@ -380,7 +380,7 @@ public: if (!SomePHI) break; if (CheckIfPHIMatches(SomePHI)) { - RecordMatchingPHI(SomePHI); + RecordMatchingPHIs(BlockList); break; } // Match failed: clear all the PHITag values. @@ -437,38 +437,17 @@ public: return true; } - /// RecordMatchingPHI - For a PHI node that matches, record it and its input - /// PHIs in both the BBMap and the AvailableVals mapping. - void RecordMatchingPHI(PhiT *PHI) { - SmallVector WorkList; - WorkList.push_back(PHI); - - // Record this PHI. - BlkT *BB = PHI->getParent(); - ValT PHIVal = Traits::GetPHIValue(PHI); - (*AvailableVals)[BB] = PHIVal; - BBMap[BB]->AvailableVal = PHIVal; - - while (!WorkList.empty()) { - PHI = WorkList.pop_back_val(); - - // Iterate through the PHI's incoming values. - for (typename Traits::PHI_iterator I = Traits::PHI_begin(PHI), - E = Traits::PHI_end(PHI); I != E; ++I) { - ValT IncomingVal = I.getIncomingValue(); - PhiT *IncomingPHI = Traits::ValueIsPHI(IncomingVal, Updater); - if (!IncomingPHI) continue; - BB = IncomingPHI->getParent(); - BBInfo *Info = BBMap[BB]; - if (!Info || Info->AvailableVal) - continue; - - // Record the PHI and add it to the worklist. - (*AvailableVals)[BB] = IncomingVal; - Info->AvailableVal = IncomingVal; - WorkList.push_back(IncomingPHI); + /// RecordMatchingPHIs - For each PHI node that matches, record it in both + /// the BBMap and the AvailableVals mapping. + void RecordMatchingPHIs(BlockListTy *BlockList) { + for (typename BlockListTy::iterator I = BlockList->begin(), + E = BlockList->end(); I != E; ++I) + if (PhiT *PHI = (*I)->PHITag) { + BlkT *BB = PHI->getParent(); + ValT PHIVal = Traits::GetPHIValue(PHI); + (*AvailableVals)[BB] = PHIVal; + BBMap[BB]->AvailableVal = PHIVal; } - } } }; diff --git a/test/Transforms/ScalarRepl/phi-cycle.ll b/test/Transforms/ScalarRepl/phi-cycle.ll new file mode 100644 index 00000000000..cb5101c2dd8 --- /dev/null +++ b/test/Transforms/ScalarRepl/phi-cycle.ll @@ -0,0 +1,77 @@ +; RUN: opt -S -scalarrepl-ssa < %s | FileCheck %s +; rdar://10589171 + +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +%struct.foo = type { i32, i32 } + +@.str = private unnamed_addr constant [6 x i8] c"x=%d\0A\00", align 1 + +define i32 @main(i32 %argc, i8** nocapture %argv) nounwind uwtable { +entry: + %f = alloca %struct.foo, align 4 + %x.i = getelementptr inbounds %struct.foo* %f, i64 0, i32 0 + store i32 1, i32* %x.i, align 4 + %y.i = getelementptr inbounds %struct.foo* %f, i64 0, i32 1 + br label %while.cond.i + +; CHECK: while.cond.i: +; CHECK-NEXT: %tmp = phi i32 [ 1, %entry ], [ %tmp2, %while.cond.backedge.i ] +; CHECK-NEXT: %pos.0.i = phi i32 [ 1, %entry ], [ %xtmp.i, %while.cond.backedge.i ] +; CHECK-NEXT: %left.0.i = phi i32 [ 1, %entry ], [ %dec.i, %while.cond.backedge.i ] +; CHECK-NOT: phi +while.cond.i: ; preds = %while.cond.backedge.i, %entry + %tmp = phi i32 [ 1, %entry ], [ %tmp2, %while.cond.backedge.i ] + %pos.0.i = phi i32 [ 1, %entry ], [ %xtmp.i, %while.cond.backedge.i ] + %left.0.i = phi i32 [ 1, %entry ], [ %dec.i, %while.cond.backedge.i ] + %cmp.i = icmp sgt i32 %left.0.i, 0 + br i1 %cmp.i, label %while.body.i, label %while.cond.i.func.exit_crit_edge + +while.cond.i.func.exit_crit_edge: ; preds = %while.cond.i + br label %func.exit + +while.body.i: ; preds = %while.cond.i + %dec.i = add nsw i32 %left.0.i, -1 + switch i32 1, label %while.body.i.func.exit_crit_edge [ + i32 0, label %while.cond.backedge.i + i32 1, label %sw.bb.i + ] + +while.body.i.func.exit_crit_edge: ; preds = %while.body.i + br label %func.exit + +sw.bb.i: ; preds = %while.body.i + %cmp2.i = icmp eq i32 %tmp, 1 + br i1 %cmp2.i, label %if.then.i, label %if.end.i + +if.then.i: ; preds = %sw.bb.i + store i32 %pos.0.i, i32* %x.i, align 4 + br label %if.end.i + +; CHECK: if.end.i: +; CHECK-NEXT: %tmp1 = phi i32 [ %pos.0.i, %if.then.i ], [ %tmp, %sw.bb.i ] +; CHECK-NOT: phi +if.end.i: ; preds = %if.then.i, %sw.bb.i + %tmp1 = phi i32 [ %pos.0.i, %if.then.i ], [ %tmp, %sw.bb.i ] + store i32 %tmp1, i32* %y.i, align 4 + br label %while.cond.backedge.i + +; CHECK: while.cond.backedge.i: +; CHECK-NEXT: %tmp2 = phi i32 [ %tmp1, %if.end.i ], [ %tmp, %while.body.i ] +; CHECK-NOT: phi +while.cond.backedge.i: ; preds = %if.end.i, %while.body.i + %tmp2 = phi i32 [ %tmp1, %if.end.i ], [ %tmp, %while.body.i ] + %xtmp.i = add i32 %pos.0.i, 1 + br label %while.cond.i + +; CHECK: func.exit: +; CHECK-NOT: load +; CHECK: %call = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([6 x i8]* @.str, i64 0, i64 0), i32 %tmp) nounwind +func.exit: ; preds = %while.body.i.func.exit_crit_edge, %while.cond.i.func.exit_crit_edge + %tmp3 = load i32* %x.i, align 4 + %call = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([6 x i8]* @.str, i64 0, i64 0), i32 %tmp3) nounwind + ret i32 0 +} + +declare i32 @printf(i8* nocapture, ...) nounwind