4 Commits

Author SHA1 Message Date
Nirav Dave
d6351340bb [DAGCombiner] If a TokenFactor would be merged into its user, consider the user later.
Summary:
A number of optimizations are inhibited by single-use TokenFactors not
being merged into the TokenFactor using it. This makes we consider if
we can do the merge immediately.

Most tests changes here are due to the change in visitation causing
minor reorderings and associated reassociation of paired memory
operations.

CodeGen tests with non-reordering changes:

  X86/aligned-variadic.ll -- memory-based add folded into stored leaq
  value.

  X86/constant-combiners.ll -- Optimizes out overlap between stores.

  X86/pr40631_deadstore_elision -- folds constant byte store into
  preceding quad word constant store.

Reviewers: RKSimon, craig.topper, spatel, efriedma, courbet

Reviewed By: courbet

Subscribers: dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, eraman, hiraditya, kbarton, jrtc27, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59260

llvm-svn: 356068
2019-03-13 17:07:09 +00:00
Matthias Braun
6b898beb8e X86: Do not use llc -march in tests.
`llc -march` is problematic because it only switches the target
architecture, but leaves the operating system unchanged. This
occasionally leads to indeterministic tests because the OS from
LLVM_DEFAULT_TARGET_TRIPLE is used.

However we can simply always use `llc -mtriple` instead. This changes
all the tests to do this to avoid people using -march when they copy and
paste parts of tests.

See also the discussion in https://reviews.llvm.org/D35287

llvm-svn: 309774
2017-08-02 00:28:10 +00:00
Reid Kleckner
fb69308568 Implement X86 code generation for musttail
Currently, musttail codegen is relying on sibcall optimization, and
reporting a fatal error if fails.  Sibcall optimization fails when stack
arguments need to be modified, which is insufficient for musttail.

The logic for moving arguments in memory safely is already implemented
for GuaranteedTailCallOpt.  This change merely arranges for musttail
calls to use it.

No functional change for GuaranteedTailCallOpt.

Reviewers: espindola

Differential Revision: http://reviews.llvm.org/D3493

llvm-svn: 207598
2014-04-29 23:55:41 +00:00
Reid Kleckner
5772b77789 Add 'musttail' marker to call instructions
This is similar to the 'tail' marker, except that it guarantees that
tail call optimization will occur.  It also comes with convervative IR
verification rules that ensure that tail call optimization is possible.

Reviewers: nicholas

Differential Revision: http://llvm-reviews.chandlerc.com/D3240

llvm-svn: 207143
2014-04-24 20:14:34 +00:00