If a MI uses the same register more than once, only mark one of them as 'kill'.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66363 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/VirtRegMap.cpp b/lib/CodeGen/VirtRegMap.cpp
index 461d839f1c0965027bbd822edfeb229922fe2e6a..aae13d8da6148b359e2111c46b3290cfbcb9425e 100644 (file)
--- a/lib/CodeGen/VirtRegMap.cpp
+++ b/lib/CodeGen/VirtRegMap.cpp
@@ -1317,6 +1317,23 @@ void LocalSpiller::TransferDeadness(MachineBasicBlock *MBB, unsigned CurDist,
   }
 }
 
+/// hasLaterNon2AddrUse - If the MI has another use of the specified virtual
+/// register later and it's not a two-address, return true. That means it's
+/// safe to mark the current use at 'i' isKill.
+static bool hasLaterNon2AddrUse(MachineInstr &MI, unsigned i, unsigned VirtReg){
+  const TargetInstrDesc &TID = MI.getDesc();
+
+  ++i;
+  for (unsigned e = TID.getNumOperands(); i != e; ++i) {
+    const MachineOperand &MO = MI.getOperand(i);
+    if (!MO.isReg() || MO.getReg() != VirtReg)
+      continue;
+    if (TID.getOperandConstraint(i, TOI::TIED_TO) == -1)
+      return true;
+  }
+  return false;
+}
+
 /// rewriteMBB - Keep track of which spills are available even after the
 /// register allocator is done with them.  If possible, avid reloading vregs.
 void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM,
@@ -1581,9 +1598,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM,
         // apply, reuse it.
         bool CanReuse = true;
         int ti = TID.getOperandConstraint(i, TOI::TIED_TO);
-        if (ti != -1 &&
-            MI.getOperand(ti).isReg() &&
-            MI.getOperand(ti).getReg() == VirtReg) {
+        if (ti != -1) {
           // Okay, we have a two address operand.  We can reuse this physreg as
           // long as we are allowed to clobber the value and there isn't an
           // earlier def that has already clobbered the physreg.
@@ -1637,9 +1652,10 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM,
             PotentialDeadStoreSlots.push_back(ReuseSlot);
           }
 
-          // Assumes this is the last use. IsKill will be unset if reg is reused
-          // unless it's a two-address operand.
-          if (ti == -1)
+          // Mark is isKill if it's there no other uses of the same virtual
+          // register and it's not a two-address operand. IsKill will be
+          // unset if reg is reused.
+          if (ti == -1 && !hasLaterNon2AddrUse(MI, i, VirtReg))
             MI.getOperand(i).setIsKill();
           continue;
         }  // CanReuse

diff --git a/test/CodeGen/ARM/2009-03-07-SpillerBug.ll b/test/CodeGen/ARM/2009-03-07-SpillerBug.ll
new file mode 100644 (file)
index 0000000..7556616
--- /dev/null
+++ b/test/CodeGen/ARM/2009-03-07-SpillerBug.ll
@@ -0,0 +1,78 @@
+; RUN: llvm-as < %s | llc -mtriple=armv6-apple-darwin9 -mattr=+vfp2
+; rdar://6653182
+
+       %struct.ggBRDF = type { i32 (...)** }
+       %struct.ggPoint2 = type { [2 x double] }
+       %struct.ggPoint3 = type { [3 x double] }
+       %struct.ggSpectrum = type { [8 x float] }
+       %struct.ggSphere = type { %struct.ggPoint3, double }
+       %struct.mrDiffuseAreaSphereLuminaire = type { %struct.mrSphere, %struct.ggSpectrum }
+       %struct.mrDiffuseCosineSphereLuminaire = type { %struct.mrDiffuseAreaSphereLuminaire }
+       %struct.mrSphere = type { %struct.ggBRDF, %struct.ggSphere }
+
+declare void @llvm.memcpy.i32(i8* nocapture, i8* nocapture, i32, i32) nounwind
+
+declare double @llvm.sqrt.f64(double) nounwind readonly
+
+declare double @sin(double) nounwind readonly
+
+declare double @acos(double) nounwind readonly
+
+define i32 @_ZNK34mrDiffuseSolidAngleSphereLuminaire18selectVisiblePointERK8ggPoint3RK9ggVector3RK8ggPoint2dRS0_Rd(%struct.mrDiffuseCosineSphereLuminaire* nocapture %this, %struct.ggPoint3* nocapture %x, %struct.ggPoint3* nocapture %unnamed_arg, %struct.ggPoint2* nocapture %uv, double %unnamed_arg2, %struct.ggPoint3* nocapture %on_light, double* nocapture %invProb) nounwind {
+entry:
+       %0 = call double @llvm.sqrt.f64(double 0.000000e+00) nounwind           ; <double> [#uses=4]
+       %1 = fcmp ult double 0.000000e+00, %0           ; <i1> [#uses=1]
+       br i1 %1, label %bb3, label %bb7
+
+bb3:           ; preds = %entry
+       %2 = fdiv double 1.000000e+00, 0.000000e+00             ; <double> [#uses=1]
+       %3 = mul double 0.000000e+00, %2                ; <double> [#uses=2]
+       %4 = call double @llvm.sqrt.f64(double 0.000000e+00) nounwind           ; <double> [#uses=1]
+       %5 = fdiv double 1.000000e+00, %4               ; <double> [#uses=2]
+       %6 = mul double %3, %5          ; <double> [#uses=2]
+       %7 = mul double 0.000000e+00, %5                ; <double> [#uses=2]
+       %8 = mul double %3, %7          ; <double> [#uses=1]
+       %9 = sub double %8, 0.000000e+00                ; <double> [#uses=1]
+       %10 = mul double 0.000000e+00, %6               ; <double> [#uses=1]
+       %11 = sub double 0.000000e+00, %10              ; <double> [#uses=1]
+       %12 = sub double -0.000000e+00, %11             ; <double> [#uses=1]
+       %13 = mul double %0, %0         ; <double> [#uses=2]
+       %14 = sub double %13, 0.000000e+00              ; <double> [#uses=1]
+       %15 = call double @llvm.sqrt.f64(double %14)            ; <double> [#uses=1]
+       %16 = mul double 0.000000e+00, %15              ; <double> [#uses=1]
+       %17 = fdiv double %16, %0               ; <double> [#uses=1]
+       %18 = add double 0.000000e+00, %17              ; <double> [#uses=1]
+       %19 = call double @acos(double %18) nounwind readonly           ; <double> [#uses=1]
+       %20 = load double* null, align 4                ; <double> [#uses=1]
+       %21 = mul double %20, 0x401921FB54442D18                ; <double> [#uses=1]
+       %22 = call double @sin(double %19) nounwind readonly            ; <double> [#uses=2]
+       %23 = mul double %22, 0.000000e+00              ; <double> [#uses=2]
+       %24 = mul double %6, %23                ; <double> [#uses=1]
+       %25 = mul double %7, %23                ; <double> [#uses=1]
+       %26 = call double @sin(double %21) nounwind readonly            ; <double> [#uses=1]
+       %27 = mul double %22, %26               ; <double> [#uses=2]
+       %28 = mul double %9, %27                ; <double> [#uses=1]
+       %29 = mul double %27, %12               ; <double> [#uses=1]
+       %30 = add double %24, %28               ; <double> [#uses=1]
+       %31 = add double 0.000000e+00, %29              ; <double> [#uses=1]
+       %32 = add double %25, 0.000000e+00              ; <double> [#uses=1]
+       %33 = add double %30, 0.000000e+00              ; <double> [#uses=1]
+       %34 = add double %31, 0.000000e+00              ; <double> [#uses=1]
+       %35 = add double %32, 0.000000e+00              ; <double> [#uses=1]
+       %36 = bitcast %struct.ggPoint3* %x to i8*               ; <i8*> [#uses=1]
+       call void @llvm.memcpy.i32(i8* null, i8* %36, i32 24, i32 4) nounwind
+       store double %33, double* null, align 8
+       br i1 false, label %_Z20ggRaySphereIntersectRK6ggRay3RK8ggSphereddRd.exit, label %bb5.i.i.i
+
+bb5.i.i.i:             ; preds = %bb3
+       unreachable
+
+_Z20ggRaySphereIntersectRK6ggRay3RK8ggSphereddRd.exit:         ; preds = %bb3
+       %37 = sub double %13, 0.000000e+00              ; <double> [#uses=0]
+       %38 = sub double -0.000000e+00, %34             ; <double> [#uses=0]
+       %39 = sub double -0.000000e+00, %35             ; <double> [#uses=0]
+       ret i32 1
+
+bb7:           ; preds = %entry
+       ret i32 0
+}