[llvm] r339788 - [RegisterCoalescer] Reset VNInfo def when copying segments over

[Krzysztof Parzyszek via llvm-commits]

Author: kparzysz
Date: Wed Aug 15 09:21:53 2018
New Revision: 339788

URL: http://llvm.org/viewvc/llvm-project?rev=339788&view=rev
Log:
[RegisterCoalescer] Reset VNInfo def when copying segments over

Added:
    llvm/trunk/test/CodeGen/SystemZ/subregliveness-03.ll
Modified:
    llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp

Modified: llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp?rev=339788&r1=339787&r2=339788&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp (original)
+++ llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp Wed Aug 15 09:21:53 2018
@@ -686,13 +686,16 @@ bool RegisterCoalescer::hasOtherReaching
 
 /// Copy segments with value number @p SrcValNo from liverange @p Src to live
 /// range @Dst and use value number @p DstValNo there.
-static void addSegmentsWithValNo(LiveRange &Dst, VNInfo *DstValNo,
+static bool addSegmentsWithValNo(LiveRange &Dst, VNInfo *DstValNo,
                                  const LiveRange &Src, const VNInfo *SrcValNo) {
+  bool Changed = false;
   for (const LiveRange::Segment &S : Src.segments) {
     if (S.valno != SrcValNo)
       continue;
     Dst.addSegment(LiveRange::Segment(S.start, S.end, DstValNo));
+    Changed = true;
   }
+  return Changed;
 }
 
 bool RegisterCoalescer::removeCopyByCommutingDef(const CoalescerPair &CP,
@@ -889,7 +892,8 @@ bool RegisterCoalescer::removeCopyByComm
           ? SR.getNextValue(CopyIdx, Allocator)
           : SR.getVNInfoAt(CopyIdx);
         assert(BSubValNo != nullptr);
-        addSegmentsWithValNo(SR, BSubValNo, SA, ASubValNo);
+        if (addSegmentsWithValNo(SR, BSubValNo, SA, ASubValNo))
+          BSubValNo->def = ASubValNo->def;
       });
     }
   }

Added: llvm/trunk/test/CodeGen/SystemZ/subregliveness-03.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/SystemZ/subregliveness-03.ll?rev=339788&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/SystemZ/subregliveness-03.ll (added)
+++ llvm/trunk/test/CodeGen/SystemZ/subregliveness-03.ll Wed Aug 15 09:21:53 2018
@@ -0,0 +1,51 @@
+; RUN: llc -mtriple=s390x-linux-gnu -mcpu=z13 -systemz-subreg-liveness < %s | FileCheck %s
+
+; Check for successful compilation.
+; CHECK: aghi %r15, -160
+
+target datalayout = "E-m:e-i1:8:16-i8:8:16-i64:64-f128:64-v128:64-a:8:16-n32:64"
+target triple = "s390x-ibm-linux"
+
+%0 = type { i8*, i32, i32 }
+
+declare i8* @Perl_sv_grow(%0*, i64) #0
+
+; Function Attrs: nounwind
+define signext i32 @Perl_yylex() #1 {
+bb:
+  br label %bb1
+
+bb1:                                              ; preds = %bb3, %bb
+  %tmp = phi i8* [ %tmp8, %bb3 ], [ undef, %bb ]
+  %tmp2 = icmp eq i8 undef, 0
+  br i1 %tmp2, label %bb9, label %bb3
+
+bb3:                                              ; preds = %bb1
+  %tmp4 = ptrtoint i8* %tmp to i64
+  %tmp5 = sub i64 %tmp4, 0
+  %tmp6 = shl i64 %tmp5, 32
+  %tmp7 = ashr exact i64 %tmp6, 32
+  %tmp8 = getelementptr inbounds i8, i8* null, i64 %tmp7
+  br label %bb1
+
+bb9:                                              ; preds = %bb1
+  br i1 undef, label %bb10, label %bb15
+
+bb10:                                             ; preds = %bb9
+  %tmp11 = ptrtoint i8* %tmp to i64
+  %tmp12 = sub i64 %tmp11, 0
+  %tmp13 = call i8* @Perl_sv_grow(%0* nonnull undef, i64 undef) #2
+  %tmp14 = getelementptr inbounds i8, i8* %tmp13, i64 %tmp12
+  br label %bb15
+
+bb15:                                             ; preds = %bb10, %bb9
+  %tmp16 = phi i8* [ %tmp14, %bb10 ], [ %tmp, %bb9 ]
+  %tmp17 = call i8* @Perl_uvuni_to_utf8(i8* %tmp16, i64 undef) #2
+  unreachable
+}
+
+declare i8* @Perl_uvuni_to_utf8(i8*, i64) #0
+
+attributes #0 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="z13" "target-features"="+transactional-execution,+vector" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="z13" "target-features"="+transactional-execution,+vector" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #2 = { nounwind }