3 files changed, 26 insertions, 14 deletions

diff --git a/compiler/optimizing/register_allocator.cc b/compiler/optimizing/register_allocator.cc
index cecc210cbf..9911f8b574 100644
--- a/compiler/optimizing/register_allocator.cc
+++ b/compiler/optimizing/register_allocator.cc
@@ -213,7 +213,7 @@ void RegisterAllocator::ProcessInstruction(HInstruction* instruction) {
           LiveInterval* interval =
               LiveInterval::MakeTempInterval(allocator_, Primitive::kPrimInt);
           temp_intervals_.Add(interval);
-          interval->AddRange(position, position + 1);
+          interval->AddTempUse(instruction, i);
           unhandled_core_intervals_.Add(interval);
           break;
         }
@@ -222,7 +222,7 @@ void RegisterAllocator::ProcessInstruction(HInstruction* instruction) {
           LiveInterval* interval =
               LiveInterval::MakeTempInterval(allocator_, Primitive::kPrimDouble);
           temp_intervals_.Add(interval);
-          interval->AddRange(position, position + 1);
+          interval->AddTempUse(instruction, i);
           if (codegen_->NeedsTwoRegisters(Primitive::kPrimDouble)) {
             interval->AddHighInterval(true);
             LiveInterval* high = interval->GetHighInterval();
@@ -1695,8 +1695,6 @@ void RegisterAllocator::Resolve() {
   }
 
   // Assign temp locations.
-  HInstruction* current = nullptr;
-  size_t temp_index = 0;
   for (size_t i = 0; i < temp_intervals_.Size(); ++i) {
     LiveInterval* temp = temp_intervals_.Get(i);
     if (temp->IsHighInterval()) {
@@ -1704,25 +1702,20 @@ void RegisterAllocator::Resolve() {
       continue;
     }
     HInstruction* at = liveness_.GetTempUser(temp);
-    if (at != current) {
-      temp_index = 0;
-      current = at;
-    }
+    size_t temp_index = liveness_.GetTempIndex(temp);
     LocationSummary* locations = at->GetLocations();
     switch (temp->GetType()) {
       case Primitive::kPrimInt:
-        locations->SetTempAt(
-            temp_index++, Location::RegisterLocation(temp->GetRegister()));
+        locations->SetTempAt(temp_index, Location::RegisterLocation(temp->GetRegister()));
         break;
 
       case Primitive::kPrimDouble:
         if (codegen_->NeedsTwoRegisters(Primitive::kPrimDouble)) {
           Location location = Location::FpuRegisterPairLocation(
               temp->GetRegister(), temp->GetHighInterval()->GetRegister());
-          locations->SetTempAt(temp_index++, location);
+          locations->SetTempAt(temp_index, location);
         } else {
-          locations->SetTempAt(
-              temp_index++, Location::FpuRegisterLocation(temp->GetRegister()));
+          locations->SetTempAt(temp_index, Location::FpuRegisterLocation(temp->GetRegister()));
         }
         break;
 
diff --git a/compiler/optimizing/ssa_liveness_analysis.cc b/compiler/optimizing/ssa_liveness_analysis.cc
index 56ccd717cf..0f3973e5fb 100644
--- a/compiler/optimizing/ssa_liveness_analysis.cc
+++ b/compiler/optimizing/ssa_liveness_analysis.cc
@@ -318,6 +318,8 @@ static int RegisterOrLowRegister(Location location) {
 
 int LiveInterval::FindFirstRegisterHint(size_t* free_until) const {
   DCHECK(!IsHighInterval());
+  if (IsTemp()) return kNoRegister;
+
   if (GetParent() == this && defined_by_ != nullptr) {
     // This is the first interval for the instruction. Try to find
     // a register based on its definition.
diff --git a/compiler/optimizing/ssa_liveness_analysis.h b/compiler/optimizing/ssa_liveness_analysis.h
index b57029d1a7..bc78dc2e76 100644
--- a/compiler/optimizing/ssa_liveness_analysis.h
+++ b/compiler/optimizing/ssa_liveness_analysis.h
@@ -180,6 +180,15 @@ class LiveInterval : public ArenaObject<kArenaAllocMisc> {
   // This interval is the result of a split.
   bool IsSplit() const { return parent_ != this; }
 
+  void AddTempUse(HInstruction* instruction, size_t temp_index) {
+    DCHECK(IsTemp());
+    DCHECK(first_use_ == nullptr) << "A temporary can only have one user";
+    size_t position = instruction->GetLifetimePosition();
+    first_use_ = new (allocator_) UsePosition(
+        instruction, temp_index, /* is_environment */ false, position, first_use_);
+    AddRange(position, position + 1);
+  }
+
   void AddUse(HInstruction* instruction, size_t input_index, bool is_environment) {
     // Set the use within the instruction.
     size_t position = instruction->GetLifetimePosition() + 1;
@@ -856,7 +865,15 @@ class SsaLivenessAnalysis : public ValueObject {
   HInstruction* GetTempUser(LiveInterval* temp) const {
     // A temporary shares the same lifetime start as the instruction that requires it.
     DCHECK(temp->IsTemp());
-    return GetInstructionFromPosition(temp->GetStart() / 2);
+    HInstruction* user = GetInstructionFromPosition(temp->GetStart() / 2);
+    DCHECK_EQ(user, temp->GetFirstUse()->GetUser());
+    return user;
+  }
+
+  size_t GetTempIndex(LiveInterval* temp) const {
+    // We use the input index to store the index of the temporary in the user's temporary list.
+    DCHECK(temp->IsTemp());
+    return temp->GetFirstUse()->GetInputIndex();
   }
 
   size_t GetMaxLifetimePosition() const {