llvm-project

Commit Graph

Author	SHA1	Message	Date
Eli Friedman	89b80f1239	[ARM] Lower "(x<<c) > 0x80000000U" to "lsls" on Thumb1. This is extremely specific, but saves three instructions when it's legal. I don't think the code can be usefully generalized. Differential Revision: https://reviews.llvm.org/D65351 llvm-svn: 367492	2019-07-31 23:19:21 +00:00
Eli Friedman	2f45ec1c39	[ARM] Transform compare of masked value to shift on Thumb1. Thumb1 has very limited immediate modes, so turning an "and" into a shift can save multiple instructions. It's possible to simplify the generated code for test2 and test3 in cmp-and-fold.ll a little more, but I'll implement that as a followup. Differential Revision: https://reviews.llvm.org/D65175 llvm-svn: 367491	2019-07-31 23:17:34 +00:00

Author

SHA1

Message

Date

Eli Friedman

89b80f1239

[ARM] Lower "(x<<c) > 0x80000000U" to "lsls" on Thumb1.

This is extremely specific, but saves three instructions when it's
legal.  I don't think the code can be usefully generalized.

Differential Revision: https://reviews.llvm.org/D65351

llvm-svn: 367492

2019-07-31 23:19:21 +00:00

Eli Friedman

2f45ec1c39

[ARM] Transform compare of masked value to shift on Thumb1.

Thumb1 has very limited immediate modes, so turning an "and" into a
shift can save multiple instructions.

It's possible to simplify the generated code for test2 and test3 in
cmp-and-fold.ll a little more, but I'll implement that as a followup.

Differential Revision: https://reviews.llvm.org/D65175

llvm-svn: 367491

2019-07-31 23:17:34 +00:00

2 Commits