the tail of a block may make that block a new candidate for duplication.

llvm-svn: 89264

llvm-svn: 89254

When TwoAddressInstructionPass deletes a dead instruction, make sure that all
register kills are accounted for. The 2-addr register does not get special
treatment.

llvm-svn: 89246

Verify LiveVariables information when present.

llvm-svn: 89241

llvm-svn: 89240

Fixed the in-place spiller and trivial rewriter, which had been broken by the recent SlotIndexes work.

llvm-svn: 89238

llvm-svn: 89225

when LiveVariables is available.

The -split-phi-edges is now gone, and so is the hack to disable it when using
the local register allocator. The PHIElimination pass no longer has
LiveVariables as a prerequisite - that is what broke the local allocator.
Instead we do critical edge splitting when possible - that is when
LiveVariables is available.

llvm-svn: 89213

contents of the block to be duplicated.  Use this for ARM Cortex A8/9 to
be more aggressive tail duplicating indirect branches, since it makes it
much more likely that they will be predicted in the branch target buffer.
Testcase coming soon.

llvm-svn: 89187

llvm-svn: 89167

llvm-svn: 89142

llvm-svn: 89139

llvm-svn: 89130

llvm-svn: 89129

The local register allocator doesn't like it when LiveVariables is run.
We should also disable edge splitting under -O0, but that has to wait a bit.

llvm-svn: 89125

unnecessary.  It is broken because the "isIdenticalTo" check should be
negated.  If that is fixed, this code causes the CodeGen/X86/tail-opts.ll
test to fail, in the dont_merge_oddly function.  And, I confirmed that the
regression is real -- the generated code is worse.  As far as I can tell,
that tail-opts.ll test is checking for what this code is supposed to handle
and we're doing the right thing anyway.

llvm-svn: 89121

llvm-svn: 89114

folding optimizations.

llvm-svn: 89109

It was too difficult to keep the heuristics for merging and duplication
consistent.

llvm-svn: 89105

llvm-svn: 89082

llvm-svn: 89075

llvm-svn: 89066

more than one place. No intended functionality change.

llvm-svn: 89024

llvm-svn: 89021

unconditional branches or fallthroghes. Instcombine/SimplifyCFG
should be simplifying branches with known conditions.

This fixes some problems caused by these transformations not
updating the MachineBasicBlock CFG.

llvm-svn: 89017

uninitialized memory.

llvm-svn: 88985

llvm-svn: 88973

llvm-svn: 88956

llvm-svn: 88953

llvm-svn: 88940

llvm-svn: 88939

llvm-svn: 88932

llvm-svn: 88929

llvm-svn: 88927

Support spill comments.

Have the asm printer emit a comment if an instruction is a spill or
reload and have the spiller mark copies it introdues so the asm printer
can also annotate those.

llvm-svn: 88911

llvm-svn: 88899

llvm-svn: 88895

Make sure when ProcessImplicitDefs removes a copy which kills its source reg that it
removes the copy from said reg's Kills list.

llvm-svn: 88881

Fix for the original bug in PR5495 - Look at uses as well as defs when determining the PHI-copy insert point.

- Patch by Andrew Canis!

llvm-svn: 88880

Added an assert to the PBQP allocator to catch infinite cost solutions which might otherwise lead to miscompilations.

llvm-svn: 88829