From be27d61cbc5b6659b47ed5f2601236356763fc85 Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Fri, 9 Oct 2009 01:17:11 +0000
Subject: [PATCH] Reset kill markers after live interval is reconstructed.

llvm-svn: 83608
---
 llvm/lib/CodeGen/PreAllocSplitting.cpp | 28 ++++++++++++++++-----
 llvm/test/CodeGen/X86/pre-split11.ll   | 34 ++++++++++++++++++++++++++
 2 files changed, 56 insertions(+), 6 deletions(-)
 create mode 100644 llvm/test/CodeGen/X86/pre-split11.ll

diff --git a/llvm/lib/CodeGen/PreAllocSplitting.cpp b/llvm/lib/CodeGen/PreAllocSplitting.cpp
index b13047992c2b..8fa07d4d9afc 100644
--- a/llvm/lib/CodeGen/PreAllocSplitting.cpp
+++ b/llvm/lib/CodeGen/PreAllocSplitting.cpp
@@ -778,6 +778,24 @@ void PreAllocSplitting::ReconstructLiveInterval(LiveInterval* LI) {
     LI->addRange(LiveRange(DefIdx, LIs->getNextSlot(DefIdx), DeadVN));
     DeadVN->addKill(DefIdx);
   }
+
+  // Update kill markers.
+  for (LiveInterval::vni_iterator VI = LI->vni_begin(), VE = LI->vni_end();
+       VI != VE; ++VI) {
+    VNInfo* VNI = *VI;
+    for (unsigned i = 0, e = VNI->kills.size(); i != e; ++i) {
+      LiveIndex KillIdx = VNI->kills[i];
+      if (KillIdx.isPHIIndex())
+        continue;
+      MachineInstr *KillMI = LIs->getInstructionFromIndex(KillIdx);
+      if (KillMI) {
+        MachineOperand *KillMO = KillMI->findRegisterUseOperand(CurrLI->reg);
+        if (KillMO)
+          // It could be a dead def.
+          KillMO->setIsKill();
+      }
+    }
+  }
 }
 
 /// RenumberValno - Split the given valno out into a new vreg, allowing it to
@@ -1102,7 +1120,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
       return false; // Def is dead. Do nothing.
     
     if ((SpillMI = FoldSpill(LI->reg, RC, DefMI, Barrier,
-                            BarrierMBB, SS, RefsInMBB))) {
+                             BarrierMBB, SS, RefsInMBB))) {
       SpillIndex = LIs->getInstructionIndex(SpillMI);
     } else {
       // Check if it's possible to insert a spill after the def MI.
@@ -1118,11 +1136,9 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
         if (SpillPt == DefMBB->end())
           return false; // No gap to insert spill.
       }
-      // Add spill. The store instruction kills the register if def is before
-      // the barrier in the barrier block.
+      // Add spill. 
       SS = CreateSpillStackSlot(CurrLI->reg, RC);
-      TII->storeRegToStackSlot(*DefMBB, SpillPt, CurrLI->reg,
-                               DefMBB == BarrierMBB, SS, RC);
+      TII->storeRegToStackSlot(*DefMBB, SpillPt, CurrLI->reg, false, SS, RC);
       SpillMI = prior(SpillPt);
       LIs->InsertMachineInstrInMaps(SpillMI, SpillIndex);
     }
@@ -1150,7 +1166,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
                           LIs->getDefIndex(RestoreIndex));
 
   ReconstructLiveInterval(CurrLI);
-  
+
   if (!FoldedRestore) {
     LiveIndex RestoreIdx = LIs->getInstructionIndex(prior(RestorePt));
     RestoreIdx = LIs->getDefIndex(RestoreIdx);
diff --git a/llvm/test/CodeGen/X86/pre-split11.ll b/llvm/test/CodeGen/X86/pre-split11.ll
new file mode 100644
index 000000000000..0a9f4e33f34c
--- /dev/null
+++ b/llvm/test/CodeGen/X86/pre-split11.ll
@@ -0,0 +1,34 @@
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=+sse2 -pre-alloc-split | FileCheck %s
+
+@.str = private constant [28 x i8] c"\0A\0ADOUBLE            D = %f\0A\00", align 1 ; <[28 x i8]*> [#uses=1]
+@.str1 = private constant [37 x i8] c"double to long    l1 = %ld\09\09(0x%lx)\0A\00", align 8 ; <[37 x i8]*> [#uses=1]
+@.str2 = private constant [35 x i8] c"double to uint   ui1 = %u\09\09(0x%x)\0A\00", align 8 ; <[35 x i8]*> [#uses=1]
+@.str3 = private constant [37 x i8] c"double to ulong  ul1 = %lu\09\09(0x%lx)\0A\00", align 8 ; <[37 x i8]*> [#uses=1]
+
+define i32 @main(i32 %argc, i8** nocapture %argv) nounwind ssp {
+; CHECK: movsd %xmm0, (%rsp)
+entry:
+  %0 = icmp sgt i32 %argc, 4                      ; <i1> [#uses=1]
+  br i1 %0, label %bb, label %bb2
+
+bb:                                               ; preds = %entry
+  %1 = getelementptr inbounds i8** %argv, i64 4   ; <i8**> [#uses=1]
+  %2 = load i8** %1, align 8                      ; <i8*> [#uses=1]
+  %3 = tail call double @atof(i8* %2) nounwind    ; <double> [#uses=1]
+  br label %bb2
+
+bb2:                                              ; preds = %bb, %entry
+  %storemerge = phi double [ %3, %bb ], [ 2.000000e+00, %entry ] ; <double> [#uses=4]
+  %4 = fptoui double %storemerge to i32           ; <i32> [#uses=2]
+  %5 = fptoui double %storemerge to i64           ; <i64> [#uses=2]
+  %6 = fptosi double %storemerge to i64           ; <i64> [#uses=2]
+  %7 = tail call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([28 x i8]* @.str, i64 0, i64 0), double %storemerge) nounwind ; <i32> [#uses=0]
+  %8 = tail call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([37 x i8]* @.str1, i64 0, i64 0), i64 %6, i64 %6) nounwind ; <i32> [#uses=0]
+  %9 = tail call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([35 x i8]* @.str2, i64 0, i64 0), i32 %4, i32 %4) nounwind ; <i32> [#uses=0]
+  %10 = tail call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([37 x i8]* @.str3, i64 0, i64 0), i64 %5, i64 %5) nounwind ; <i32> [#uses=0]
+  ret i32 0
+}
+
+declare double @atof(i8* nocapture) nounwind readonly
+
+declare i32 @printf(i8* nocapture, ...) nounwind