llvm-project

Commit Graph

Author	SHA1	Message	Date
Kai Nacke	d09bb4614b	PR16726: extend rol/ror matching C-like languages promote types like unsigned short to unsigned int before performing an arithmetic operation. Currently the rotate matcher in the DAGCombiner does not consider this situation. This commit extends the DAGCombiner in the way that the pattern (or (shl ([az]ext x), (ext y)), (srl ([az]ext x), (ext (sub 32, y)))) is folded into ([az]ext (rotl x, y)) The matching is restricted to aext and zext because in this cases the upper bits are either undefined or known. Test case is included. This fixes PR16726. llvm-svn: 191049	2013-09-19 23:00:28 +00:00
Kai Nacke	2d967b2751	Revert PR16726: extend rol/ror matching There is a buildbot failure. Need to investigate this. llvm-svn: 191048	2013-09-19 22:53:36 +00:00
Kai Nacke	4eaf6444fa	PR16726: extend rol/ror matching C-like languages promote types like unsigned short to unsigned int before performing an arithmetic operation. Currently the rotate matcher in the DAGCombiner does not consider this situation. This commit extends the DAGCombiner in the way that the pattern (or (shl ([az]ext x), (ext y)), (srl ([az]ext x), (ext (sub 32, y)))) is folded into ([az]ext (rotl x, y)) The matching is restricted to aext and zext because in this cases the upper bits are either undefined or known. Test case is included. This fixes PR16726. llvm-svn: 191045	2013-09-19 22:36:39 +00:00

Author

SHA1

Message

Date

Kai Nacke

d09bb4614b

PR16726: extend rol/ror matching

C-like languages promote types like unsigned short to unsigned int before
performing an arithmetic operation. Currently the rotate matcher in the
DAGCombiner does not consider this situation.

This commit extends the DAGCombiner in the way that the pattern

(or (shl ([az]ext x), (*ext y)), (srl ([az]ext x), (*ext (sub 32, y))))

is folded into

([az]ext (rotl x, y))

The matching is restricted to aext and zext because in this cases the upper
bits are either undefined or known. Test case is included.

This fixes PR16726.

llvm-svn: 191049

2013-09-19 23:00:28 +00:00

Kai Nacke

2d967b2751

Revert PR16726: extend rol/ror matching

There is a buildbot failure. Need to investigate this.

llvm-svn: 191048

2013-09-19 22:53:36 +00:00

Kai Nacke

4eaf6444fa

PR16726: extend rol/ror matching

C-like languages promote types like unsigned short to unsigned int before
performing an arithmetic operation. Currently the rotate matcher in the
DAGCombiner does not consider this situation.

This commit extends the DAGCombiner in the way that the pattern

(or (shl ([az]ext x), (*ext y)), (srl ([az]ext x), (*ext (sub 32, y))))

is folded into

([az]ext (rotl x, y))

The matching is restricted to aext and zext because in this cases the upper
bits are either undefined or known. Test case is included.

This fixes PR16726.

llvm-svn: 191045

2013-09-19 22:36:39 +00:00

3 Commits