Temporarily reverting r56683. This is causing a failure during the build of llvm...

Temporarily reverting r56683. This is causing a failure during the build of llvm-gcc:

/Volumes/Gir/devel/llvm/clean/llvm-gcc.obj/./gcc/xgcc -B/Volumes/Gir/devel/llvm/clean/llvm-gcc.obj/./gcc/ -B/Volumes/Gir/devel/llvm/clean/llvm-gcc.install/i386-apple-darwin9.5.0/bin/ -B/Volumes/Gir/devel/llvm/clean/llvm-gcc.install/i386-apple-darwin9.5.0/lib/ -isystem /Volumes/Gir/devel/llvm/clean/llvm-gcc.install/i386-apple-darwin9.5.0/include -isystem /Volumes/Gir/devel/llvm/clean/llvm-gcc.install/i386-apple-darwin9.5.0/sys-include -mmacosx-version-min=10.4 -O2  -O2 -g -O2  -DIN_GCC    -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition  -isystem ./include  -fPIC -pipe -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED  -I. -I. -I../../llvm-gcc.src/gcc -I../../llvm-gcc.src/gcc/. -I../../llvm-gcc.src/gcc/../include -I./../intl -I../../llvm-gcc.src/gcc/../libcpp/include  -I../../llvm-gcc.src/gcc/../libdecnumber -I../libdecnumber -I/Volumes/Gir/devel/llvm/clean/llvm.obj/include -I/Volumes/Gir/devel/llvm/clean/llvm.src/include -fexceptions -fvisibility=hidden -DHIDE_EXPORTS -c ../../llvm-gcc.src/gcc/unwind-dw2-fde-darwin.c -o libgcc/./unwind-dw2-fde-darwin.o
Assertion failed: (TargetRegisterInfo::isVirtualRegister(regA) && TargetRegisterInfo::isVirtualRegister(regB) && "cannot update physical register live information"), function runOnMachineFunction, file /Volumes/Gir/devel/llvm/clean/llvm.src/lib/CodeGen/TwoAddressInstructionPass.cpp, line 311.
../../llvm-gcc.src/gcc/unwind-dw2.c:1527: internal compiler error: Abort trap
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://developer.apple.com/bugreporter> for instructions.
{standard input}:3521:non-relocatable subtraction expression, "_dwarf_reg_size_table" minus "L20$pb"
{standard input}:3521:symbol: "_dwarf_reg_size_table" can't be undefined in a subtraction expression
{standard input}:3520:non-relocatable subtraction expression, "_dwarf_reg_size_table" minus "L20$pb"
...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56703 91177308-0d34-0410-b5e6-96231b3b80d8