C is a constant which can be sign-extended from 8 bits without value loss,
and op is one of: add, sub, imul, and, or, xor.

This allows the JIT to emit the one byte version of the constant instead of
the two or 4 byte version.  Because these instructions are very common, this
can save a LOT of code space.  For example, I sampled two benchmarks, 176.gcc
and 254.gap.

BM        Old     New    Reduction
176.gcc 2673621 2548962  4.89%
254.gap  498261  475104  4.87%

Note that while the percentage is not spectacular, this did eliminate
124.6 _KILOBYTES_ of codespace from gcc.  Not bad.

Note that this doesn't effect the llc version at all, because the assembler
already does this optimization.

llvm-svn: 9284

llvm-svn: 9282

llvm-svn: 9281

llvm-svn: 9280

* Implement R1 = R2 * C where R1 and R2 are 32 or 16 bits. This avoids an
  extra copy into a register, reducing register pressure.

llvm-svn: 9278

  getelementptr code path for use by other code paths (like malloc and alloca).
* Optimize comparisons with zero
* Generate neg, not, inc, and dec instructions, when possible.

This gives some code size wins, which might translate into performance.  We'll
see tommorow in the nightly tester.

llvm-svn: 9267

llvm-svn: 9266

This fixes PR#44.

llvm-svn: 9252

This also fixes miscompilation of 176.gcc.

llvm-svn: 9249

llvm-svn: 9224

displacement.

llvm-svn: 9210

llvm-svn: 9204

llvm-svn: 9202

llvm-svn: 9187

llvm-svn: 9171

llvm-svn: 9135

off the bottom of the stack.  This fixes PR#41

llvm-svn: 9114

X86/linux.  :(  The problem is that a signal delivered while the function
is executing could clobber the functions stack.  This is a partial fix
for PR41.

llvm-svn: 9113

llvm-svn: 9027

llvm-svn: 8892

llvm-svn: 8871

Moved enum and command-line option in separate file. Also added function that returns the user selected register allocator to the caller.

llvm-svn: 8819

llvm-svn: 8815

llvm-svn: 8805

llvm-svn: 8804

command line if VERBOSE=1

llvm-svn: 8453

llvm-svn: 8452

much cleaner and easier.
Labeled .td as a suffix for tblgen files in Makefile.rules.
Modified build rules so that source files generated during the build are placed
in the build directory and not the source directory (and not in a Debug
directory).  This makes the system cleaner and allows us to have a read-only
source tree.

llvm-svn: 8424

  into the struct case.
* Extend printConstantValueOnly to print .zero's if the initializer is zero
* Delete dead isConstantFunctionPointerRef function
* Emit the appropriate assembly for the various linkage types!

llvm-svn: 8417

llvm-svn: 8411

llvm-svn: 8408

Adjusted Makefile to work with new autoconf-style object root.
Specifically, use the new -I option of tblgen to find include files.

llvm-svn: 8379

llvm-svn: 8312

until we implement unwinding.
Add support for the invoke instruction, which codegens just like a call with
a branch after it.

The end effect of this change is that programs using the invoke instruction,
but never unwinding, will work fine.  Programs that unwind will abort until
we get unwind support.

llvm-svn: 8187

llvm-svn: 8132

llvm-svn: 8127

llvm-svn: 8019

llvm-svn: 7951

llvm-svn: 7944

This bug caused miscompilation of programs using 'struct stat', but only if
compiled with support for 64-bit filesystems.  This could in theory effect
other things, but only if the LLVM code shared data structures with native code.

llvm-svn: 7928