llvm-project

Commit Graph

Author	SHA1	Message	Date
Sanjay Patel	138328e45c	[SDAG] commute setcc operands to match a subtract If we have: R = sub X, Y P = cmp Y, X ...then flipping the operands in the compare instruction can allow using a subtract that sets compare flags. Motivated by diffs in D58875 - not sure if this changes anything there, but this seems like a good thing independent of that. There's a more involved version of this transform already in IR (in instcombine although that seems misplaced to me) - see "swapMayExposeCSEOpportunities()". Differential Revision: https://reviews.llvm.org/D63958 llvm-svn: 365711	2019-07-10 23:23:54 +00:00
Sanjay Patel	573b241c68	[Lanai] auto-generate complete test checks; NFC This file will fail with a common codegen transform that I'm looking at, and I can't tell if that's an improvement or regression based on the sparse checking. llvm-svn: 364684	2019-06-28 20:45:32 +00:00
Jacques Pienaar	6d3eecc843	[lanai] Use peephole optimizer to generate more conditional ALU operations. Summary: * Similiar to the ARM backend yse the peephole optimizer to generate more conditional ALU operations; * Add predicated type with default always true to RR instructions in LanaiInstrInfo.td; * Move LanaiSetflagAluCombiner into optimizeCompare; * The ASM parser can currently only handle explicitly specified CC, so specify ".t" (true) where needed in the ASM test; * Remove unused MachineOperand flags; Reviewers: eliben Subscribers: aemerson Differential Revision: http://reviews.llvm.org/D22072 llvm-svn: 274807	2016-07-07 23:36:04 +00:00

Author

SHA1

Message

Date

Sanjay Patel

138328e45c

[SDAG] commute setcc operands to match a subtract

If we have:

R = sub X, Y
P = cmp Y, X

...then flipping the operands in the compare instruction can allow using a subtract that sets compare flags.

Motivated by diffs in D58875 - not sure if this changes anything there,
but this seems like a good thing independent of that.

There's a more involved version of this transform already in IR (in instcombine
although that seems misplaced to me) - see "swapMayExposeCSEOpportunities()".

Differential Revision: https://reviews.llvm.org/D63958

llvm-svn: 365711

2019-07-10 23:23:54 +00:00

Sanjay Patel

573b241c68

[Lanai] auto-generate complete test checks; NFC

This file will fail with a common codegen transform that
I'm looking at, and I can't tell if that's an improvement
or regression based on the sparse checking.

llvm-svn: 364684

2019-06-28 20:45:32 +00:00

Jacques Pienaar

6d3eecc843

[lanai] Use peephole optimizer to generate more conditional ALU operations.

Summary:
* Similiar to the ARM backend yse the peephole optimizer to generate more conditional ALU operations;
* Add predicated type with default always true to RR instructions in LanaiInstrInfo.td;
* Move LanaiSetflagAluCombiner into optimizeCompare;
* The ASM parser can currently only handle explicitly specified CC, so specify ".t" (true) where needed in the ASM test;
* Remove unused MachineOperand flags;

Reviewers: eliben

Subscribers: aemerson

Differential Revision: http://reviews.llvm.org/D22072

llvm-svn: 274807

2016-07-07 23:36:04 +00:00

3 Commits