LiveInterval::MergeValueNumberInto instead of trying to extend LiveRanges and
getting it wrong.

This fixed PR8249 where a valno with a multi-segment live range was defined by
an identity copy created by RemoveCopyByCommutingDef. Some of the live
segments disappeared.

llvm-svn: 115385

llvm-svn: 115384

llvm-svn: 115378

llvm-svn: 115377

Thread the determination of branch prediction hit rates back through the if-conversion heuristic APIs.  For now,
stick with a constant estimate of 90% (branch predictors are good!), but we might find that we want to provide
more nuanced estimates in the future.

llvm-svn: 115364

Fix code gen crash reported in PR 8235. We still lose debug info for the unused argument here. This is a known limitation recorded debuginfo-tests/trunk/dbg-declare2.ll function 'f6' test case.

llvm-svn: 115323

llvm-svn: 115310

llvm-svn: 115300

llvm-svn: 115294

The x86_mmx type is used for MMX intrinsics, parameters and
return values where these use MMX registers, and is also
supported in load, store, and bitcast.

Only the above operations generate MMX instructions, and optimizations
do not operate on or produce MMX intrinsics. 

MMX-sized vectors <2 x i32> etc. are lowered to XMM or split into
smaller pieces.  Optimizations may occur on these forms and the
result casted back to x86_mmx, provided the result feeds into a
previous existing x86_mmx operation.

The point of all this is prevent optimizations from introducing
MMX operations, which is unsafe due to the EMMS problem.

llvm-svn: 115243

edited during emission.

If the basic block ends in a switch that gets lowered to a jump table, any
phis at the default edge were getting updated wrong. The jump table data
structure keeps a pointer to the header blocks that wasn't getting updated
after the MBB is split.

This bug was exposed on 32-bit Linux when disabling critical edge splitting in
codegen prepare.

The fix is to uipdate stale MBB pointers whenever a block is split during
emission.

llvm-svn: 115191

llvm-svn: 115102

pipeline forwarding path.

llvm-svn: 115098

llvm-svn: 115097

llvm-svn: 115089

UnreachableBlockElim could incorrectly return false when it had not modified the CFG, but HAD modified some PHI nodes.  Fixes PR8174.

llvm-svn: 115083

llvm-svn: 115067

llvm-svn: 115002

llvm-svn: 114999

knows about them. This is not necessary on 10.6 and later.

llvm-svn: 114997

estimates.

llvm-svn: 114981

Rather than having arbitrary cutoffs, actually try to cost model the conversion.

For now, the constants are tuned to more or less match our existing behavior, but these will be
changed to reflect realistic values as this work proceeds.

llvm-svn: 114973

llvm-svn: 114969

llvm-svn: 114920

and asserts.

llvm-svn: 114843

support aligned comm.  Detect when compiling for 10.4 and don't
emit an alignment for comm.  THis will hopefully fix PR8198.

llvm-svn: 114817

Fixed some tests to avoid LiveIntervals::getInstructionFromIndex(..) overhead where possible. Thanks to Jakob for the suggestions.

llvm-svn: 114798

llvm-svn: 114794

Removed VNInfo::isDefAccurate(). Def "accuracy" can be checked by testing whether LiveIntervals::getInstructionFromIndex(def) returns NULL.

llvm-svn: 114791

llvm-svn: 114779

and it will be removed shortly.

llvm-svn: 114778

llvm-svn: 114776

llvm-svn: 114767

llvm-svn: 114750

llvm-svn: 114736

Revert 114634 for now since buildbot claim it broke Clang self-hosting. I doubt it but it's possible it's exposing another bug somewhere.

llvm-svn: 114681

Patch by Nathan Jeffords!

llvm-svn: 114661

llvm-svn: 114634

close to their sources to facilitate coalescing.

llvm-svn: 114631

when the unconditional branch destination is the fallthrough block. The
canonicalization makes it easier to allow optimizations on DAGs to invert
conditional branches. The branch folding pass (and AnalyzeBranch) will clean up
the unnecessary unconditional branches later.

This is one of the patches leading up to disabling codegen prepare critical edge
splitting.

llvm-svn: 114630