Eventually this pass will provide substantially better code in the interim between when we
have a crappy isel and nice isel.  Unfortunately doing so requires fixing the backend to
actually SUPPORT all of the fancy addressing modes that we now generate, and writing a DCE
pass for machine code.  Each of these is a fairly substantial job, so this will remain disabled
for the immediate future.  :(

llvm-svn: 10276

folding of instructions into addressing modes.  This creates lots of dead
instructions, which are currently not deleted.  It also creates a lot of
instructions that the X86 backend currently cannot handle.  :(

llvm-svn: 10275

llvm-svn: 10274

llvm-svn: 10270

the other way around, instead of failing a large, tumor-like assertion.

llvm-svn: 10171

llvm-svn: 10170

llvm-svn: 10168

llvm-svn: 10069

llvm-svn: 9903

llvm-svn: 9761

llvm-svn: 9758

get just the filename and not the full path, just use the filename directly.

llvm-svn: 9730

return the number of instructions added to/removed from the basic block
passed as their first argument.

Note: This is only needed because we use a std::vector instead of an
ilist to keep MachineBasicBlock instructions. Inserting an instruction
to a MachineBasicBlock invalidates all iterators to the basic
block. The return value can be used to update an index to the machine
basic block instruction vector and circumvent the iterator elimination
problem but this is really not needed if we move to a better
representation.

llvm-svn: 9704

llvm-svn: 9694

strings with the stuff that used to print to an ostream directly.  We now NEVER build
up big strings, only to print them once they are formed.

llvm-svn: 9686

llvm-svn: 9684

* Emit bools as 1/0 instead of true/false, fixing compilation of eon and
  PR 83 & Jello/2003-11-03-GlobalBool.llx

llvm-svn: 9683

Implement mul/div/rem constant expressions

llvm-svn: 9424

* Convert tabs to spaces
* Make code fit within 80 columns

llvm-svn: 9416

llvm-svn: 9360

llvm-svn: 9321

llvm-svn: 9312

Header files will be on the way.

llvm-svn: 9298

llvm-svn: 9295

llvm-svn: 9288

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