Revert patches that caused the problem. Evan, please investigate and reapply
when you've discovered the problem.

llvm-svn: 34399

- When coalescing a copy MI, if its destination is "dead", propagate the
  property to the source MI's destination if there are no intervening uses.
- Detect dead function live-in's and remove them.

llvm-svn: 34383

llvm-svn: 34302

registers. Make sure liveinterval analysis is correctly creating live ranges
for them.

llvm-svn: 34217

llvm-svn: 32698

now cerr, cout, and NullStream resp.

llvm-svn: 32298

llvm-svn: 32296

is 'unsigned'.

llvm-svn: 32279

llvm-svn: 32113

llvm-svn: 32098

llvm-svn: 31992

llvm-svn: 31783

LiveRanges, creates a new LiveInterval from them. The LiveRanges should
have existed already in another LiveInterval, but removed.

llvm-svn: 31780

llvm-svn: 31760

llvm-svn: 31633

llvm-svn: 31561

by 40%, FreeBench/fourinarow by 20%, and many other programs 10-25%.

On PPC, this speeds up fourinarow by 18%, and probably other things as well.

llvm-svn: 31504

llvm-svn: 31500

X86.  If happy, I'll enable this by default.

llvm-svn: 31493

llvm-svn: 31408

Turn on -Wunused and -Wno-unused-parameter. Clean up most of the resulting
fall out by removing unused variables. Remaining warnings have to do with
unused functions (I didn't want to delete code without review) and unused
variables in generated code. Maintainers should clean up the remaining
issues when they see them. All changes pass DejaGnu tests and Olden.

llvm-svn: 31380

is faster and is needed for future improvements.

llvm-svn: 30383

actually *removes* one of the operands, instead of just assigning both operands
the same register.  This make reasoning about instructions unnecessarily complex,
because you need to know if you are before or after register allocation to match
up operand #'s with the target description file.

Changing this also gets rid of a bunch of hacky code in various places.

This patch also includes changes to fold loads into cmp/test instructions in
the X86 backend, along with a significant simplification to the X86 spill
folding code.

llvm-svn: 30108

llvm-svn: 30099

llvm-svn: 30098

llvm-svn: 30066

llvm-svn: 30065

Restore it, which re-fixes X86/2006-08-21-ExtraMovInst.ll

llvm-svn: 30050

method for joining the live ranges instead of the fully-general one.

llvm-svn: 30049

need recursion.

llvm-svn: 30015

analysis 16% on crafty.

Wrap long lines.

llvm-svn: 30012

crafty with and without it).  Removing it speeds up live intervals 6%.

llvm-svn: 30010

llvm-svn: 29996

llvm-svn: 29995

llvm-svn: 29994

llvm-svn: 29989

number of copies, potentially defining live ranges that appear to have
differing value numbers that become identical when coallsced.  Among other
things, this fixes CodeGen/X86/shift-coalesce.ll and PR687.

llvm-svn: 29968

llvm-svn: 29921

llvm-svn: 29910

llvm-svn: 29896