Commit Graph

21 Commits

Author SHA1 Message Date
Simon Pilgrim b49d5f3b53 [DAGCombiner] Add X / X -> 1 & X % X -> 0 folds
Adds more divrem folds to try and get in sync with InstructionSimplify

Differential Revision: https://reviews.llvm.org/D50636

llvm-svn: 340919
2018-08-29 11:30:16 +00:00
Simon Pilgrim eb6a3cbb28 [X86] Make requested test changes from D50636
The tests were relying on X / X -> 1 and X % X -> 0 combines not happening in the DAG.

llvm-svn: 340682
2018-08-25 14:16:03 +00:00
Simon Pilgrim 4aaf48013d [X86] Add tests showing missing div/rem 0, X -> 0 combines
llvm-svn: 339562
2018-08-13 13:29:54 +00:00
Craig Topper d8734450a2 [DAGCombiner] Fold X - (-Y *Z) -> X + (Y * Z)
llvm-svn: 337518
2018-07-20 01:40:03 +00:00
Craig Topper c12c5d421f [DAGCombiner] Teach DAGCombiner that A-(-B) is A+B.
We already knew A+(-B) is A-B in visitAdd. This does the opposite for visitSub.

llvm-svn: 337502
2018-07-19 22:24:43 +00:00
Simon Pilgrim df9d59771b [DAGCombiner] Support non-uniform X%C -> X-(X/C)*C folds
First stage in PR38057 - support non-uniform constant vectors in the combine to reuse the division-by-constant logic.

We can definitely do better for srem pow2 remainders (and avoid that extra multiply....) but this at least helps keep everything on the vector unit.

Differential Revision: https://reviews.llvm.org/D48975

llvm-svn: 336774
2018-07-11 09:22:42 +00:00
Simon Pilgrim 9bd9fef446 [X86] Add srem/udiv/urem by constant tests
Match the tests in combine-sdiv.ll

llvm-svn: 336694
2018-07-10 16:08:28 +00:00
Simon Pilgrim efe84b9d12 [X86][SSE] Add srem x, (1 << c) combine tests
Now that D45806 has landed we can start trying to avoid scalarizing srem by constant - these tests demonstrate some example cases.

llvm-svn: 336360
2018-07-05 15:15:47 +00:00
Simon Pilgrim 9855b39380 [DAGCombine] visitREM - Don't assume that one divrem isn't driving another
Under some circumstances the divrems won't have been combined together before getting to this code.

So replace the assertion with a if() guard to not expand to X-((X/C)*C) to give the other combine chance to happen.

Reduced from OSS-Fuzz #6883
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=6883

llvm-svn: 327424
2018-03-13 17:17:15 +00:00
Sanjay Patel b7e13938a9 [x86] consolidate and add tests for undef binop folds; NFC
As was already shown in the div/rem tests and noted in PR36305,
the behavior is inconsistent, but it's not limited to div/rem only.

llvm-svn: 324678
2018-02-08 23:21:44 +00:00
Simon Pilgrim ab84a9a65d [X86] Add srem/udiv/urem by one combine tests
llvm-svn: 321826
2018-01-04 22:08:36 +00:00
Simon Pilgrim e7c06423c1 [X86] Add scalar undef sdiv/srem/udiv/urem combine tests
llvm-svn: 321823
2018-01-04 21:33:19 +00:00
Simon Pilgrim 208fab193b [X86] Add common CHECK prefix for tests without SSE/AVX codegen
llvm-svn: 321810
2018-01-04 18:23:46 +00:00
Simon Pilgrim d6923083ba Regenerate broadcast constant comment
llvm-svn: 321808
2018-01-04 18:21:33 +00:00
Simon Pilgrim 5643b40d91 [X86] Show missed combine for X/X for SDIV/UDIV and X%X for SREM/UREM
llvm-svn: 321807
2018-01-04 18:20:46 +00:00
Francis Visoiu Mistrih 25528d6de7 [CodeGen] Unify MBB reference format in both MIR and debug output
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

llvm-svn: 319665
2017-12-04 17:18:51 +00:00
Simon Pilgrim 05ab8ffc7e [DAGCombiner] Try to use SelectionDAG::isKnownToBeAPowerOfTwo instead of just APInt::isPowerOf2
Generalize sdiv/udiv/srem/urem combines using APInt::isPowerOf2, which only works for const/splat-const values, to call SelectionDAG::isKnownToBeAPowerOfTwo instead which recognises many more cases.

Added a DAGCombiner::BuildLogBase2 helper since PowerOf2 combines often involve taking the log2 of such a value.

Differential Revision: https://reviews.llvm.org/D27714

llvm-svn: 289654
2016-12-14 15:08:13 +00:00
Simon Pilgrim ebe58191c8 [X86][SSE] Add AVX1 tests to sdiv/udiv srem/urem combine tests
As requested on D27714

llvm-svn: 289652
2016-12-14 14:39:51 +00:00
Simon Pilgrim b08c98f125 [X86][SSE] Add support for combining target shuffles to UNPCKL/UNPCKH.
llvm-svn: 288663
2016-12-05 11:25:13 +00:00
Simon Pilgrim f534573e8c [DAGCombiner] Enable srem(x.y) -> urem(x,y) combine for vectors
SelectionDAG::SignBitIsZero (via SelectionDAG::computeKnownBits) has supported vectors since rL280927

llvm-svn: 285123
2016-10-25 21:20:18 +00:00
Simon Pilgrim efd5643419 [X86][SSE] Added vector srem combine tests
llvm-svn: 285121
2016-10-25 21:14:11 +00:00