Merge MRI::isPhysRegOrOverlapUsed() into isPhysRegUsed().

All callers of these functions really want the isPhysRegOrOverlapUsed()
functionality which also checks aliases. For historical reasons, targets
without register aliases were calling isPhysRegUsed() instead.

Change isPhysRegUsed() to also check aliases, and switch all
isPhysRegOrOverlapUsed() callers to isPhysRegUsed().

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166117 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 10 insertions, 11 deletions

diff --git a/include/llvm/CodeGen/MachineRegisterInfo.h b/include/llvm/CodeGen/MachineRegisterInfo.h
index 670640a715..46731978fd 100644
--- a/include/llvm/CodeGen/MachineRegisterInfo.h
+++ b/include/llvm/CodeGen/MachineRegisterInfo.h
@@ -357,14 +357,13 @@ public:
   //===--------------------------------------------------------------------===//
 
   /// isPhysRegUsed - Return true if the specified register is used in this
-  /// function.  This only works after register allocation.
+  /// function. Also check for clobbered aliases and registers clobbered by
+  /// function calls with register mask operands.
+  ///
+  /// This only works after register allocation. It is primarily used by
+  /// PrologEpilogInserter to determine which callee-saved registers need
+  /// spilling.
   bool isPhysRegUsed(unsigned Reg) const {
-    return UsedPhysRegs.test(Reg) || UsedPhysRegMask.test(Reg);
-  }
-
-  /// isPhysRegOrOverlapUsed - Return true if Reg or any overlapping register
-  /// is used in this function.
-  bool isPhysRegOrOverlapUsed(unsigned Reg) const {
     if (UsedPhysRegMask.test(Reg))
       return true;
     for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI)
diff --git a/lib/CodeGen/ExecutionDepsFix.cpp b/lib/CodeGen/ExecutionDepsFix.cpp
index 2311842671..ed78f19421 100644
--- a/lib/CodeGen/ExecutionDepsFix.cpp
+++ b/lib/CodeGen/ExecutionDepsFix.cpp
@@ -657,7 +657,7 @@ bool ExeDepsFix::runOnMachineFunction(MachineFunction &mf) {
   bool anyregs = false;
   for (TargetRegisterClass::const_iterator I = RC->begin(), E = RC->end();
        I != E; ++I)
-    if (MF->getRegInfo().isPhysRegOrOverlapUsed(*I)) {
+    if (MF->getRegInfo().isPhysRegUsed(*I)) {
       anyregs = true;
       break;
     }
diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp
index 86df0a127b..77554d691c 100644
--- a/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/lib/CodeGen/PrologEpilogInserter.cpp
@@ -227,7 +227,7 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) {
   std::vector<CalleeSavedInfo> CSI;
   for (unsigned i = 0; CSRegs[i]; ++i) {
     unsigned Reg = CSRegs[i];
-    if (Fn.getRegInfo().isPhysRegOrOverlapUsed(Reg)) {
+    if (Fn.getRegInfo().isPhysRegUsed(Reg)) {
       // If the reg is modified, save it!
       CSI.push_back(CalleeSavedInfo(Reg));
     }
diff --git a/lib/Target/ARM/ARMFrameLowering.cpp b/lib/Target/ARM/ARMFrameLowering.cpp
index 3e70d57823..1d4bbb74d3 100644
--- a/lib/Target/ARM/ARMFrameLowering.cpp
+++ b/lib/Target/ARM/ARMFrameLowering.cpp
@@ -1176,7 +1176,7 @@ static void checkNumAlignedDPRCS2Regs(MachineFunction &MF) {
   MachineRegisterInfo &MRI = MF.getRegInfo();
   unsigned NumSpills = 0;
   for (; NumSpills < 8; ++NumSpills)
-    if (!MRI.isPhysRegOrOverlapUsed(ARM::D8 + NumSpills))
+    if (!MRI.isPhysRegUsed(ARM::D8 + NumSpills))
       break;
 
   // Don't do this for just one d-register. It's not worth it.
@@ -1249,7 +1249,7 @@ ARMFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
   for (unsigned i = 0; CSRegs[i]; ++i) {
     unsigned Reg = CSRegs[i];
     bool Spilled = false;
-    if (MF.getRegInfo().isPhysRegOrOverlapUsed(Reg)) {
+    if (MF.getRegInfo().isPhysRegUsed(Reg)) {
       Spilled = true;
       CanEliminateFrame = false;
     }