commit b7e11e400dabced046e7ec53a66926716563bb36
author Hal Finkel <hfinkel@anl.gov> Wed Mar 27 00:02:20 2013 +0000
committer Hal Finkel <hfinkel@anl.gov> Wed Mar 27 00:02:20 2013 +0000
tree ac0269c393018ee12ba343e3e1f3fa47d8368cb3
parent ca442a4a1aabf6199e5aee09ec604e79916d9b92

Don't spill PPC VRSAVE on non-Darwin (even in SjLj)

As Bill Schmidt pointed out to me, only on Darwin do we need to spill/restore
VRSAVE in the SjLj code. For non-Darwin, don't spill/restore VRSAVE (and I've
added some asserts to make sure that we're not).

As it turns out, we're not currently handling the Darwin case correctly (I've
added a FIXME in the test case). I've tried adding various implied register
definitions/uses to force the spill without success, so I'll need to address
this later.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178096 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/PowerPC/PPCCallingConv.td

diff --git a/lib/Target/PowerPC/PPCCallingConv.td b/lib/Target/PowerPC/PPCCallingConv.td
index 2a68066..c8a29a3 100644
--- a/lib/Target/PowerPC/PPCCallingConv.td
+++ b/lib/Target/PowerPC/PPCCallingConv.td
@@ -137,7 +137,8 @@
                                         V20, V21, V22, V23, V24, V25, V26, V27,
                                         V28, V29, V30, V31)>;
 
-def CSR_NoRegs : CalleeSavedRegs<(add)>;
+def CSR_NoRegs : CalleeSavedRegs<(add VRSAVE)>;
+def CSR_NoRegs_Darwin : CalleeSavedRegs<(add)>;
 
 def CSR_NoRegs_Altivec : CalleeSavedRegs<(add (sequence "V%u", 0, 31), VRSAVE)>;
 

lib/Target/PowerPC/PPCInstrInfo.cpp

diff --git a/lib/Target/PowerPC/PPCInstrInfo.cpp b/lib/Target/PowerPC/PPCInstrInfo.cpp
index 2be8df9..1558856 100644
--- a/lib/Target/PowerPC/PPCInstrInfo.cpp
+++ b/lib/Target/PowerPC/PPCInstrInfo.cpp
@@ -509,6 +509,8 @@
                                        FrameIdx));
     NonRI = true;
   } else if (PPC::VRSAVERCRegClass.hasSubClassEq(RC)) {
+    assert(TM.getSubtargetImpl()->isDarwin() &&
+           "VRSAVE only needs spill/restore on Darwin");
     NewMIs.push_back(addFrameReference(BuildMI(MF, DL, get(PPC::SPILL_VRSAVE))
                                        .addReg(SrcReg,
                                                getKillRegState(isKill)),
@@ -627,6 +629,8 @@
                                        FrameIdx));
     NonRI = true;
   } else if (PPC::VRSAVERCRegClass.hasSubClassEq(RC)) {
+    assert(TM.getSubtargetImpl()->isDarwin() &&
+           "VRSAVE only needs spill/restore on Darwin");
     NewMIs.push_back(addFrameReference(BuildMI(MF, DL,
                                                get(PPC::RESTORE_VRSAVE),
                                                DestReg),

lib/Target/PowerPC/PPCRegisterInfo.cpp

diff --git a/lib/Target/PowerPC/PPCRegisterInfo.cpp b/lib/Target/PowerPC/PPCRegisterInfo.cpp
index d5a307e..0ebf1e8 100644
--- a/lib/Target/PowerPC/PPCRegisterInfo.cpp
+++ b/lib/Target/PowerPC/PPCRegisterInfo.cpp
@@ -114,6 +114,8 @@
   if (!Subtarget.hasAltivec())
     return CSR_NoRegs_Altivec_RegMask;
 
+  if (Subtarget.isDarwin())
+    return CSR_NoRegs_Darwin_RegMask;
   return CSR_NoRegs_RegMask;
 }