ARM: use AAPCS-style prologues for embedded MachO.

Darwin prologues save their GPRs in two stages: a narrow push of r0-r7 & lr,
followed by a wide push of the remaining registers if there are any. AAPCS uses
a single push.w instruction.

It turns out that, on average, enough registers get pushed that code is smaller
in the AAPCS prologue, which is a nice property for M-class programmers. They
also have other options available for back-traces, so can hopefully deal with
the fact that FP & LR aren't adjacent in memory.

rdar://problem/15909583

llvm-svn: 209895

1 files changed, 7 insertions, 7 deletions

diff --git a/llvm/lib/Target/ARM/ARMFrameLowering.cpp b/llvm/lib/Target/ARM/ARMFrameLowering.cpp
index 0caf4bfd77a..6888ae994c5 100644
--- a/llvm/lib/Target/ARM/ARMFrameLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMFrameLowering.cpp
@@ -220,7 +220,7 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
     case ARM::R10:
     case ARM::R11:
     case ARM::R12:
-      if (STI.isTargetMachO()) {
+      if (STI.isTargetDarwin()) {
         GPRCS2Size += 4;
         break;
       }
@@ -380,7 +380,7 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
       case ARM::R10:
       case ARM::R11:
       case ARM::R12:
-        if (STI.isTargetMachO())
+        if (STI.isTargetDarwin())
           break;
         // fallthrough
       case ARM::R0:
@@ -445,7 +445,7 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
       case ARM::R10:
       case ARM::R11:
       case ARM::R12:
-        if (STI.isTargetMachO()) {
+        if (STI.isTargetDarwin()) {
           unsigned DwarfReg =  MRI->getDwarfRegNum(Reg, true);
           unsigned Offset = MFI->getObjectOffset(FI);
           unsigned CFIIndex = MMI.addFrameInst(
@@ -810,7 +810,7 @@ void ARMFrameLowering::emitPushInst(MachineBasicBlock &MBB,
     unsigned LastReg = 0;
     for (; i != 0; --i) {
       unsigned Reg = CSI[i-1].getReg();
-      if (!(Func)(Reg, STI.isTargetMachO())) continue;
+      if (!(Func)(Reg, STI.isTargetDarwin())) continue;
 
       // D-registers in the aligned area DPRCS2 are NOT spilled here.
       if (Reg >= ARM::D8 && Reg < ARM::D8 + NumAlignedDPRCS2Regs)
@@ -888,7 +888,7 @@ void ARMFrameLowering::emitPopInst(MachineBasicBlock &MBB,
     bool DeleteRet = false;
     for (; i != 0; --i) {
       unsigned Reg = CSI[i-1].getReg();
-      if (!(Func)(Reg, STI.isTargetMachO())) continue;
+      if (!(Func)(Reg, STI.isTargetDarwin())) continue;
 
       // The aligned reloads from area DPRCS2 are not inserted here.
       if (Reg >= ARM::D8 && Reg < ARM::D8 + NumAlignedDPRCS2Regs)
@@ -1438,7 +1438,7 @@ ARMFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
     if (Spilled) {
       NumGPRSpills++;
 
-      if (!STI.isTargetMachO()) {
+      if (!STI.isTargetDarwin()) {
         if (Reg == ARM::LR)
           LRSpilled = true;
         CS1Spilled = true;
@@ -1460,7 +1460,7 @@ ARMFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
         break;
       }
     } else {
-      if (!STI.isTargetMachO()) {
+      if (!STI.isTargetDarwin()) {
         UnspilledCS1GPRs.push_back(Reg);
         continue;
       }