4 Commits

Author SHA1 Message Date
Gil Rapaport
7b88bab386 [LSR] Combine unfolded offset into invariant register
LSR reassociates constants as unfolded offsets when the constants fit as
immediate add operands, which currently prevents such constants from being
combined later with loop invariant registers.
This patch modifies GenerateCombinations() to generate a second formula which
includes the unfolded offset in the combined loop-invariant register.

This commit fixes a bug in the original patch (committed at r345114, reverted
at r345123).

Differential Revision: https://reviews.llvm.org/D51861

llvm-svn: 346390
2018-11-08 09:01:19 +00:00
Gil Rapaport
c523036fd2 Revert r345114
Investigating fails.

llvm-svn: 345123
2018-10-24 08:41:22 +00:00
Gil Rapaport
5012e7f6ac [LSR] Combine unfolded offset into invariant register
LSR reassociates constants as unfolded offsets when the constants fit as
immediate add operands, which currently prevents such constants from being
combined later with loop invariant registers.
This patch modifies GenerateCombinations() to generate a second formula which
includes the unfolded offset in the combined loop-invariant register.

Differential Revision: https://reviews.llvm.org/D51861

llvm-svn: 345114
2018-10-24 07:08:38 +00:00
Gil Rapaport
d874c3a480 [LSR] Add tests for small constants; NFC
LSR reassociates small constants that fit into add immediate operands as
unfolded offset. Since unfolded offset is not combined with loop-invariant
registers, LSR does not consider solutions that bump invariant registers by
these constants outside the loop.

llvm-svn: 341835
2018-09-10 14:56:24 +00:00