When the scheduler unfold a load folding instruction it move some of the predecessors...

rdar://7604000

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95339 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
index dea59937198bb9cc6072ac270618e937ea596364..72a07dcb04c8874b5dcb5d39efc96db446bfcdb5 100644 (file)
--- a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
+++ b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
@@ -345,6 +345,15 @@ void ScheduleDAGRRList::BacktrackBottomUp(SUnit *SU, unsigned BtCycle,
   ++NumBacktracks;
 }
 
+static bool isOperandOf(const SUnit *SU, SDNode *N) {
+  for (const SDNode *SUNode = SU->getNode(); SUNode;
+       SUNode = SUNode->getFlaggedNode()) {
+    if (SUNode->isOperandOf(N))
+      return true;
+  }
+  return false;
+}
+
 /// CopyAndMoveSuccessors - Clone the specified node and move its scheduled
 /// successors to the newly created node.
 SUnit *ScheduleDAGRRList::CopyAndMoveSuccessors(SUnit *SU) {
@@ -427,8 +436,7 @@ SUnit *ScheduleDAGRRList::CopyAndMoveSuccessors(SUnit *SU) {
          I != E; ++I) {
       if (I->isCtrl())
         ChainPreds.push_back(*I);
-      else if (I->getSUnit()->getNode() &&
-               I->getSUnit()->getNode()->isOperandOf(LoadNode))
+      else if (isOperandOf(I->getSUnit(), LoadNode))
         LoadPreds.push_back(*I);
       else
         NodePreds.push_back(*I);

diff --git a/test/CodeGen/X86/2010-02-04-SchedulerBug.ll b/test/CodeGen/X86/2010-02-04-SchedulerBug.ll
new file mode 100644 (file)
index 0000000..c966e21
--- /dev/null
+++ b/test/CodeGen/X86/2010-02-04-SchedulerBug.ll
@@ -0,0 +1,28 @@
+; RUN: llc < %s -mtriple=i386-apple-darwin11
+; rdar://7604000
+
+%struct.a_t = type { i8*, i64*, i8*, i32, i32, i64*, i64*, i64* }
+%struct.b_t = type { i32, i32, i32, i32, i64, i64, i64, i64 }
+
+define void @t(i32 %cNum, i64 %max) nounwind optsize ssp noimplicitfloat {
+entry:
+  %0 = load %struct.b_t** null, align 4 ; <%struct.b_t*> [#uses=1]
+  %1 = getelementptr inbounds %struct.b_t* %0, i32 %cNum, i32 5 ; <i64*> [#uses=1]
+  %2 = load i64* %1, align 4                      ; <i64> [#uses=1]
+  %3 = icmp ult i64 %2, %max            ; <i1> [#uses=1]
+  %4 = getelementptr inbounds %struct.a_t* null, i32 0, i32 7 ; <i64**> [#uses=1]
+  %5 = load i64** %4, align 4                     ; <i64*> [#uses=0]
+  %6 = load i64* null, align 4                    ; <i64> [#uses=1]
+  br i1 %3, label %bb2, label %bb
+
+bb:                                               ; preds = %entry
+  br label %bb3
+
+bb2:                                              ; preds = %entry
+  %7 = or i64 %6, undef                           ; <i64> [#uses=1]
+  br label %bb3
+
+bb3:                                              ; preds = %bb2, %bb
+  %misc_enables.0 = phi i64 [ undef, %bb ], [ %7, %bb2 ] ; <i64> [#uses=0]
+  ret void
+}