Commit Graph

5 Commits

Author SHA1 Message Date
Tony 1bc7bfffdb [AMDGPU] Optimize waitcnt insertion for flat memory operations
Change waitcnt insertion to check the memory operand tokens to see if
flat memory operations access VMEM in the same way it does to check if
accessing LDS. This avoids adding waitcnt for counters for address
spaces that are not accessed.

In addition, only generate the pessimistic waitcnt 0 if a flat memory
operation appears to access both VMEM and LDS.

This benefits flat memory operations that explicitly specify the
address space as GLOBAL or LOCAL.

Differential Revision: https://reviews.llvm.org/D89618
2020-10-20 22:55:12 +00:00
Quentin Colombet b3afad0463 [GlobalISel] Add a `X, Y = G_UNMERGE(G_ZEXT Z)` -> X = G_ZEXT Z; Y = 0 combine
Add a combiner helper to transform unmerge of zext into one zext and
a constant 0

Differential Revision: https://reviews.llvm.org/D87427
2020-09-14 17:27:23 -07:00
Matt Arsenault 201f770f16 GlobalISel: Add and_trivial_mask to all_combines
Also make up a new category of combines.
2020-08-27 16:42:09 -04:00
Matt Arsenault 70cd9f5b77 AMDGPU/GlobalISel: Start implementing computeKnownBitsForTargetInstr
Handle workitem intrinsics. There isn't really away to adequately test
this right now, since none of the known bits users are fine grained
enough to test the edge conditions. This triggers a number of
instances of the new 64-bit to 32-bit shift combine in the existing
tests.
2020-08-24 09:53:27 -04:00
Matt Arsenault e1644a3779 GlobalISel: Reduce G_SHL width if source is extension
shl ([sza]ext x, y) => zext (shl x, y).

Turns expensive 64 bit shifts into 32 bit if it does not overflow the
source type:

This is a port of an AMDGPU DAG combine added in
5fa289f0d8. InstCombine does this
already, but we need to do it again here to apply it to shifts
introduced for lowered getelementptrs. This will help matching
addressing modes that use 32-bit offsets in a future patch.

TableGen annoyingly assumes only a single match data operand, so
introduce a reusable struct. However, this still requires defining a
separate GIMatchData for every combine which is still annoying.

Adds a morally equivalent function to the existing
getShiftAmountTy. Without this, we would have to do try to repeatedly
query the legalizer info and guess at what type to use for the shift.
2020-08-24 09:42:40 -04:00