misched: When querying RegisterPressureTracker, always save current and max pressure.

llvm-svn: 158340

2 files changed, 16 insertions, 7 deletions

diff --git a/llvm/include/llvm/CodeGen/RegisterPressure.h b/llvm/include/llvm/CodeGen/RegisterPressure.h
index e810f8c64bb..2043155bc53 100644
--- a/llvm/include/llvm/CodeGen/RegisterPressure.h
+++ b/llvm/include/llvm/CodeGen/RegisterPressure.h
@@ -249,19 +249,22 @@ public:
 
   /// Get the pressure of each PSet after traversing this instruction bottom-up.
   void getUpwardPressure(const MachineInstr *MI,
-                         std::vector<unsigned> &PressureResult);
+                         std::vector<unsigned> &PressureResult,
+                         std::vector<unsigned> &MaxPressureResult);
 
   /// Get the pressure of each PSet after traversing this instruction top-down.
   void getDownwardPressure(const MachineInstr *MI,
-                           std::vector<unsigned> &PressureResult);
+                           std::vector<unsigned> &PressureResult,
+                           std::vector<unsigned> &MaxPressureResult);
 
   void getPressureAfterInst(const MachineInstr *MI,
-                            std::vector<unsigned> &PressureResult) {
+                            std::vector<unsigned> &PressureResult,
+                            std::vector<unsigned> &MaxPressureResult) {
     if (isTopClosed())
-      return getUpwardPressure(MI, PressureResult);
+      return getUpwardPressure(MI, PressureResult, MaxPressureResult);
 
     assert(isBottomClosed() && "Uninitialized pressure tracker");
-    return getDownwardPressure(MI, PressureResult);
+    return getDownwardPressure(MI, PressureResult, MaxPressureResult);
   }
 
 protected:
diff --git a/llvm/lib/CodeGen/RegisterPressure.cpp b/llvm/lib/CodeGen/RegisterPressure.cpp
index 52174d8f37e..43448c850a0 100644
--- a/llvm/lib/CodeGen/RegisterPressure.cpp
+++ b/llvm/lib/CodeGen/RegisterPressure.cpp
@@ -811,25 +811,31 @@ getMaxDownwardPressureDelta(const MachineInstr *MI, RegPressureDelta &Delta,
 /// Get the pressure of each PSet after traversing this instruction bottom-up.
 void RegPressureTracker::
 getUpwardPressure(const MachineInstr *MI,
-                  std::vector<unsigned> &PressureResult) {
+                  std::vector<unsigned> &PressureResult,
+                  std::vector<unsigned> &MaxPressureResult) {
   // Snapshot pressure.
   PressureResult = CurrSetPressure;
+  MaxPressureResult = P.MaxSetPressure;
 
   bumpUpwardPressure(MI);
 
   // Current pressure becomes the result. Restore current pressure.
+  P.MaxSetPressure.swap(MaxPressureResult);
   CurrSetPressure.swap(PressureResult);
 }
 
 /// Get the pressure of each PSet after traversing this instruction top-down.
 void RegPressureTracker::
 getDownwardPressure(const MachineInstr *MI,
-                    std::vector<unsigned> &PressureResult) {
+                    std::vector<unsigned> &PressureResult,
+                    std::vector<unsigned> &MaxPressureResult) {
   // Snapshot pressure.
   PressureResult = CurrSetPressure;
+  MaxPressureResult = P.MaxSetPressure;
 
   bumpDownwardPressure(MI);
 
   // Current pressure becomes the result. Restore current pressure.
+  P.MaxSetPressure.swap(MaxPressureResult);
   CurrSetPressure.swap(PressureResult);
 }