3 Commits

Author SHA1 Message Date
Keith Randall
98cb76799c cmd/compile: insert complicated x86 addressing modes as a separate pass
Use a separate compiler pass to introduce complicated x86 addressing
modes.  Loads in the normal architecture rules (for x86 and all other
platforms) can have constant offsets (AuxInt values) and symbols (Aux
values), but no more.

The complex addressing modes (x+y, x+2*y, etc.) are introduced in a
separate pass that combines loads with LEAQx ops.

Organizing rewrites this way simplifies the number of rewrites
required, as there are lots of different rule orderings that have to
be specified to ensure these complex addressing modes are always found
if they are possible.

Update #36468

Change-Id: I5b4bf7b03a1e731d6dfeb9ef19b376175f3b4b44
Reviewed-on: https://go-review.googlesource.com/c/go/+/217097
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2020-03-10 00:13:21 +00:00
Keith Randall
9f291d1fc3 cmd/compile: fix rule for combining loads with compares
Unlike normal load+op opcodes, the load+compare opcode does
not clobber its non-load argument. Allow the load+compare merge
to happen even if the non-load argument is used elsewhere.

Noticed when investigating issue #28417.

Change-Id: Ibc48d1f2e06ae76034c59f453815d263e8ec7288
Reviewed-on: https://go-review.googlesource.com/c/145097
Reviewed-by: Ainar Garipov <gugl.zadolbal@gmail.com>
Reviewed-by: Ben Shi <powerman1st@163.com>
2018-10-27 00:59:54 +00:00
Keith Randall
b1f656b1ce cmd/compile: fold address calculations into CMPload[const] ops
Makes go binary smaller by 0.2%.

I noticed this in autogenerated equal methods, and there are
probably a lot of those.

Change-Id: I4e04eb3653fbceb9dd6a4eee97ceab1fa4d10b72
Reviewed-on: https://go-review.googlesource.com/135379
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
2018-09-14 19:42:09 +00:00