[llvm-commits] [llvm] r95183 - in /llvm/trunk: lib/CodeGen/RegAllocLocal.cpp test/CodeGen/PowerPC/2007-04-30-InlineAsmEarlyClobber.ll test/CodeGen/X86/phys-reg-local-regalloc.ll

[Dale Johannesen]

Author: johannes
Date: Tue Feb  2 19:40:33 2010
New Revision: 95183

URL: http://llvm.org/viewvc/llvm-project?rev=95183&view=rev
Log:
Reapply 95050 with a tweak to check the register class.


Modified:
    llvm/trunk/lib/CodeGen/RegAllocLocal.cpp
    llvm/trunk/test/CodeGen/PowerPC/2007-04-30-InlineAsmEarlyClobber.ll
    llvm/trunk/test/CodeGen/X86/phys-reg-local-regalloc.ll

Modified: llvm/trunk/lib/CodeGen/RegAllocLocal.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/RegAllocLocal.cpp?rev=95183&r1=95182&r2=95183&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/RegAllocLocal.cpp (original)
+++ llvm/trunk/lib/CodeGen/RegAllocLocal.cpp Tue Feb  2 19:40:33 2010
@@ -764,8 +764,11 @@
     // Determine whether this is a copy instruction.  The cases where the
     // source or destination are phys regs are handled specially.
     unsigned SrcCopyReg, DstCopyReg, SrcCopySubReg, DstCopySubReg;
+    unsigned SrcCopyPhysReg = 0U;
     bool isCopy = TII->isMoveInstr(*MI, SrcCopyReg, DstCopyReg, 
                                    SrcCopySubReg, DstCopySubReg);
+    if (isCopy && TargetRegisterInfo::isVirtualRegister(SrcCopyReg))
+      SrcCopyPhysReg = getVirt2PhysRegMapSlot(SrcCopyReg);
 
     // Loop over the implicit uses, making sure that they are at the head of the
     // use order list, so they don't get reallocated.
@@ -977,13 +980,26 @@
 
         // If DestVirtReg already has a value, use it.
         if (!(DestPhysReg = getVirt2PhysRegMapSlot(DestVirtReg))) {
+          // If this is a copy try to reuse the input as the output;
+          // that will make the copy go away.
           // If this is a copy, the source reg is a phys reg, and
           // that reg is available, use that phys reg for DestPhysReg.
+          // If this is a copy, the source reg is a virtual reg, and
+          // the phys reg that was assigned to that virtual reg is now
+          // available, use that phys reg for DestPhysReg.  (If it's now
+          // available that means this was the last use of the source.)
           if (isCopy &&
               TargetRegisterInfo::isPhysicalRegister(SrcCopyReg) &&
               isPhysRegAvailable(SrcCopyReg)) {
             DestPhysReg = SrcCopyReg;
             assignVirtToPhysReg(DestVirtReg, DestPhysReg);
+          } else if (isCopy &&
+              TargetRegisterInfo::isVirtualRegister(SrcCopyReg) &&
+              SrcCopyPhysReg && isPhysRegAvailable(SrcCopyPhysReg) &&
+              MF->getRegInfo().getRegClass(DestVirtReg)->
+                               contains(SrcCopyPhysReg)) {
+            DestPhysReg = SrcCopyPhysReg;
+            assignVirtToPhysReg(DestVirtReg, DestPhysReg);
           } else
             DestPhysReg = getReg(MBB, MI, DestVirtReg);
         }

Modified: llvm/trunk/test/CodeGen/PowerPC/2007-04-30-InlineAsmEarlyClobber.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/2007-04-30-InlineAsmEarlyClobber.ll?rev=95183&r1=95182&r2=95183&view=diff

==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/2007-04-30-InlineAsmEarlyClobber.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/2007-04-30-InlineAsmEarlyClobber.ll Tue Feb  2 19:40:33 2010
@@ -1,7 +1,7 @@
 ; RUN: llc < %s | grep {subfc r3,r5,r4}
 ; RUN: llc < %s | grep {subfze r4,r2}
-; RUN: llc < %s -regalloc=local | grep {subfc r5,r4,r3}
-; RUN: llc < %s -regalloc=local | grep {subfze r2,r2}
+; RUN: llc < %s -regalloc=local | grep {subfc r2,r5,r4}
+; RUN: llc < %s -regalloc=local | grep {subfze r3,r3}
 ; The first argument of subfc must not be the same as any other register.
 
 ; PR1357

Modified: llvm/trunk/test/CodeGen/X86/phys-reg-local-regalloc.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/phys-reg-local-regalloc.ll?rev=95183&r1=95182&r2=95183&view=diff

==============================================================================
--- llvm/trunk/test/CodeGen/X86/phys-reg-local-regalloc.ll (original)
+++ llvm/trunk/test/CodeGen/X86/phys-reg-local-regalloc.ll Tue Feb  2 19:40:33 2010
@@ -1,4 +1,6 @@
 ; RUN: llc < %s -march=x86 -mtriple=i386-apple-darwin9 -regalloc=local | FileCheck %s
+; RUN: llc -O0 < %s -march=x86 -mtriple=i386-apple-darwin9 -regalloc=local | FileCheck %s
+; CHECKed instructions should be the same with or without -O0.
 
 @.str = private constant [12 x i8] c"x + y = %i\0A\00", align 1 ; <[12 x i8]*> [#uses=1]