1129 Commits

Author SHA1 Message Date
Matt Arsenault
e75afc9acf GlobalISel: Use unmerge when copying wide vectors to result registers
Avoid using G_EXTRACT and move towards a more consistent vector
legalization strategy.
2020-09-24 15:19:51 -04:00
Stanislav Mekhanoshin
27a62f6317 [AMDGPU] global-isel support for RT
Differential Revision: https://reviews.llvm.org/D87847
2020-09-24 10:29:45 -07:00
Sebastian Neubauer
6f7cd16d29 [AMDGPU] Fix v3f16 handling for getresinfo
v3f32 should not be expanded to v4f32. getresinfo with a dmask of 7
created an image sample with a v3f32 return value, which was bitcasted
to a v4f32 in constructRetValue.

Differential Revision: https://reviews.llvm.org/D88206
2020-09-24 16:03:02 +02:00
Matt Arsenault
dc08185ca7 IR: Have byref imply dereferenceable
The langref already states it does, but this wasn't implemented. Also
covers inalloca and preallocated. Also helps fix a dependence on
pointer element types.
2020-09-24 09:57:28 -04:00
Pushpinder Singh
41d6669f1f [GlobalISel][AMDGPU] Lower G_SMULH/G_UMULH
Reviewed By: arsenm, foad

Differential Revision: https://reviews.llvm.org/D85653
2020-09-23 22:25:29 -04:00
Sebastian Neubauer
a343b9b032 Revert "[AMDGPU] Insert waitcnt after returning from call"
This reverts commit ca907bfb57d8ad3ec3bcc2cff2abab7b1b933af6.

According to michel.daenzer,
> This completely broke the Mesa radeonsi driver on Navi 14. Xorg +
> xterm come up with major corruption & psychedelic colours.
2020-09-23 17:16:39 +02:00
Matt Arsenault
c463fd136e GlobalISel: Fix truncating shift amount in trunc (shl) combine
The shift amount type does not necessarily match the result type. This
was inserting a trunc from s32 to s32, which asserted. Just preserve
the original shift amount type which can be legalized later.
2020-09-23 09:07:50 -04:00
Sebastian Neubauer
ca907bfb57 [AMDGPU] Insert waitcnt after returning from call
When memory operations are outstanding on function calls, either the
caller or the callee can insert a waitcnt to ensure that all reads are
finished.
Calls need some time to be executed, so if the callee inserts the
waitcnt, filling the instruction buffer and waiting for memory will be
interleaved, hiding some latency. This comes at the cost of having a
waitcnt inside functions that may not be needed as no memory operations
are outstanding.

For function calls, this is already implemented. The same principal
applies to returns: If the caller inserts a waitcnt after the call, the
callee does not have to wait and the return and memory operation can be
run in parallel.

This commit implements waiting in the caller after returning from a
function call.

Differential Revision: https://reviews.llvm.org/D87674
2020-09-23 12:17:59 +02:00
Michael Liao
534f6e1718 [PeepholeOptimizer] Enhance the redundant COPY elimination.
- Eliminate redundant COPYs from the same register & subregister pair.

Differential Revision: https://reviews.llvm.org/D87939
2020-09-22 10:11:37 -04:00
Muhammad Omair Javaid
73a6a164b8 Revert "Reapply Revert "RegAllocFast: Rewrite and improve""
This reverts commit 55f9f87da2c2ad791b9e62cccb1c035e037444fa.

Breaks following buildbots:
http://lab.llvm.org:8011/builders/lldb-arm-ubuntu/builds/4306
http://lab.llvm.org:8011/builders/lldb-aarch64-ubuntu/builds/9154
2020-09-22 14:40:06 +05:00
Matt Arsenault
55f9f87da2 Reapply Revert "RegAllocFast: Rewrite and improve"
This reverts commit dbd53a1f0c939a55e7719c39d08179468f9ad3dc.

Needed lldb test updates
2020-09-21 15:45:27 -04:00
Eric Christopher
dbd53a1f0c Temporarily Revert "RegAllocFast: Rewrite and improve"
as it's breaking a few tests in the lldb test suite.

Bot: http://lab.llvm.org:8011/builders/lldb-arm-ubuntu/builds/4226/steps/test/logs/stdio

This reverts commit c8757ff3aa7dd7a25a6343f6ef74a70c7be04325.
2020-09-18 18:11:21 -07:00
Matt Arsenault
c8757ff3aa RegAllocFast: Rewrite and improve
This rewrites big parts of the fast register allocator. The basic
strategy of doing block-local allocation hasn't changed but I tweaked
several details:

Track register state on register units instead of physical
registers. This simplifies and speeds up handling of register aliases.
Process basic blocks in reverse order: Definitions are known to end
register livetimes when walking backwards (contrary when walking
forward then uses may or may not be a kill so we need heuristics).

Check register mask operands (calls) instead of conservatively
assuming everything is clobbered.  Enhance heuristics to detect
killing uses: In case of a small number of defs/uses check if they are
all in the same basic block and if so the last one is a killing use.
Enhance heuristic for copy-coalescing through hinting: We check the
first k defs of a register for COPYs rather than relying on there just
being a single definition.  When testing this on the full llvm
test-suite including SPEC externals I measured:

average 5.1% reduction in code size for X86, 4.9% reduction in code on
aarch64. (ranging between 0% and 20% depending on the test) 0.5%
faster compiletime (some analysis suggests the pass is slightly slower
than before, but we more than make up for it because later passes are
faster with the reduced instruction count)

Also adds a few testcases that were broken without this patch, in
particular bug 47278.

Patch mostly by Matthias Braun
2020-09-18 14:05:18 -04:00
Mirko Brkusanin
ae36c02ad0 [AMDGPU] Set DS alignment requirements to be more strict
Alignment requirements for ds_read/write_b96/b128 for gfx9 and onward are
now the same as for other GCN subtargets. This way we can avoid any
unintentional use of these instructions on systems that do not support dword
alignment and instead require natural alignment.
This also makes 'SH_MEM_CONFIG.alignment_mode == STRICT' the default.

Differential Revision: https://reviews.llvm.org/D87821
2020-09-18 15:26:24 +02:00
Matt Arsenault
88bdcbbf1a GlobalISel: Lift store value widening restriction
This doesn't change the memory size and doesn't need to worry about
non-power-of-2 sizes.
2020-09-16 14:25:07 -04:00
Matt Arsenault
71131db689 AMDGPU: Improve <2 x i24> arguments and return value handling
This was asserting for GlobalISel. For SelectionDAG, this was
passing this on the stack. Instead, scalarize this as if it were a
32-bit vector.
2020-09-16 11:21:56 -04:00
Jay Foad
90777e2924 [AMDGPU] Enable scheduling around FP MODE-setting instructions
Pre-gfx10 all MODE-setting instructions were S_SETREG_B32 which is
marked as having unmodeled side effects, which makes the machine
scheduler treat it as a barrier. Now that we have proper implicit $mode
operands we can use a no-side-effects S_SETREG_B32_mode pseudo instead
for setregs that only touch the FP MODE bits, to give the scheduler more
freedom.

Differential Revision: https://reviews.llvm.org/D87446
2020-09-16 16:10:47 +01:00
Jay Foad
54bb9e8649 [AMDGPU] Add -show-mc-encoding to setreg tests
This is a pre-commit for D87446 "[AMDGPU] Enable scheduling around FP MODE-setting instructions"
2020-09-16 16:09:47 +01:00
Volkan Keles
a4e35cc2ec GlobalISel: Add combines for G_TRUNC
https://reviews.llvm.org/D87050
2020-09-15 15:50:34 -07:00
Stanislav Mekhanoshin
277de43d88 [AMDGPU] Unify intrinsic ret/nortn interface
We have a single noret intrinsic an a lot of special handling
around it. Declare it just as any other but do not define rtn
instructions itself instead.

Differential Revision: https://reviews.llvm.org/D87719
2020-09-15 15:26:42 -07:00
Petar Avramovic
9b4fa85434 GlobalISel/IRTranslator resetTargetOptions based on function attributes
Update TargetMachine.Options with function attributes before we start
to generate MIR instructions. This allows access to correct function
attributes via TargetMachine.Options (it used to access attributes of
the function that was translated first).
This affects some existing tests with "no-nans-fp-math" attribute.
Follow-up on D87456.

Differential Revision: https://reviews.llvm.org/D87511
2020-09-15 10:26:09 +02:00
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
Quentin Colombet
d2321129bd [GlobalISel] Add X,Y<dead> = G_UNMERGE Z -> X = G_TRUNC Z
Add a combiner helper that replaces G_UNMERGE where all the destination lanes
are dead except the first one with a G_TRUNC.

Differential Revision: https://reviews.llvm.org/D87174
2020-09-14 17:27:23 -07:00
Quentin Colombet
a36278c2f8 [GlobalISel] Add G_UNMERGE(Cst) -> Cst1, Cst2, ... combine
Add a combiner helper that replaces G_UNMERGE of big constants into direct
use of smaller constants.

Differential Revision: https://reviews.llvm.org/D87166
2020-09-14 16:30:18 -07:00
Jay Foad
c799f873cb [AMDGPU] Don't cluster stores
Clustering loads has caching benefits, but as far as I know there is no
advantage to clustering stores on any AMDGPU subtargets.

The disadvantage is that it tends to increase register pressure and
restricts scheduling freedom.

Differential Revision: https://reviews.llvm.org/D85530
2020-09-14 13:40:17 +01:00
Petar Avramovic
6e2a86ed5a AMDGPU/GlobalISel Check for NoNaNsFPMath in isKnownNeverSNaN
Check for NoNaNsFPMath function attribute in isKnownNeverSNaN.
Function attributes are in held in 'TargetMachine.Options'.
Among other things, this allows selection of some patterns imported
in D87351 since G_FCANONICALIZE is not generated when isKnownNeverSNaN
returns true in lowerFMinNumMaxNum.

However we notice some incorrect results since function attributes are
not correctly written in TargetMachine.Options when next function is
processed. Take a look at @v_test_no_global_nnans_med3_f32_pat0_srcmod0,
it has "no-nans-fp-math"="false" but TargetMachine.Options still has it
set to true since first function in test file had this attribute set to
true. This will be fixed in D87511.

Differential Revision: https://reviews.llvm.org/D87456
2020-09-14 12:11:00 +02:00
Petar Avramovic
416346d1ca AMDGPU/GlobalISel/Emitter Recognize additional 'same operand checks'
The "name" of a non-leaf complex pattern (MY_PAT $op1, $op2) is
"MY_PAT:op1:op2" and the ones with same "name" represent same operand.
Add 'same operand check' for this case.

Differential Revision: https://reviews.llvm.org/D87351
2020-09-14 12:10:59 +02:00
Petar Avramovic
0c8f4cd657 AMDGPU/GlobalISel Add test for non-leaf complex patterns
GlobalIsel emitter does not import patterns where complex sub-operand
of a non-leaf complex pattern is referenced more then once. Multiple
references of complex patterns with same name and same sub-operands
represent the same operand. Document this with a test.
2020-09-14 12:10:59 +02:00
Petar Avramovic
09b8871f8d AMDGPU/GlobalISel/Emitter Support for predicate code that uses operands
Predicates with 'let PredicateCodeUsesOperands = 1' want to examine
matched operands. When we encounter predicate code that uses operands,
analyze its named operand arguments and create a map between argument
index and name. Later, when leaf node with name is encountered, emit
GIM_RecordNamedOperand that will store that operand at its argument
index in operand list. This operand list will be an argument to c++
code of the predicate.

Differential Revision: https://reviews.llvm.org/D87285
2020-09-14 10:39:56 +02:00
Amara Emerson
e5784ef8f6 [GlobalISel] Enable usage of BranchProbabilityInfo in IRTranslator.
We weren't using this before, so none of the MachineFunction CFG edges had the
branch probability information added. As a result, block placement later in the
pipeline was flying blind.

This is enabled only with optimizations enabled like SelectionDAG.

Differential Revision: https://reviews.llvm.org/D86824
2020-09-09 14:31:12 -07:00
Amara Emerson
cc76da7ada [GlobalISel] Rewrite the elide-br-by-swapping-icmp-ops combine to do less.
This combine previously tried to take sequences like:
  %cond = G_ICMP pred, a, b
  G_BRCOND %cond, %truebb
  G_BR %falsebb
%truebb:
  ...
%falsebb:
  ...

and by inverting the compare predicate and swapping branch targets, delete the
G_BR and instead have a single conditional branch to the falsebb. Since in an
earlier patch we have a combine to fold not(icmp) into just an inverted icmp,
we don't need this combine to do as much. This patch instead generalizes the
combine by just looking for:
  G_BRCOND %cond, %truebb
  G_BR %falsebb
%truebb:
  ...
%falsebb:
  ...

and then inverting the condition using a not (xor). The xor can be folded away
in a separate combine. This change also lets us avoid some optimization code
in the IRTranslator.

I also think that deleting G_BRs in the combiner is unnecessary. That's
something that targets can decide to do at selection time and could simplify
generic code in future.

Differential Revision: https://reviews.llvm.org/D86664
2020-09-09 13:08:16 -07:00
Mirko Brkusanin
43af2a6faa [AMDGPU] Workaround for LDS Misalignment bug on GFX10
Add subtarget feature check to avoid using ds_read/write_b96/128 with too
low alignment if a bug is present on that specific hardware.
Add this "feature" to GFX 10.1.1 as it is also affected.
Add global-isel test.
2020-09-09 11:46:09 +02:00
Jay Foad
4bdab2e86a [AMDGPU] Fix offset for REL32_HI relocs
The addend in a REL32 reloc needs to be adjusted to account for the
offset from the PC value returned by the s_getpc instruction to the
point where the reloc is applied. This was being done correctly for
(GOTPC)REL32_LO but not for (GOTPC)REL32_HI. This will only make a
difference if the target symbol happens to get loaded almost exactly
a multiple of 4G away from the relocated instructions.

Differential Revision: https://reviews.llvm.org/D86938
2020-09-02 10:55:55 +01:00
Amara Emerson
520ab710fb Revert "Revert "[GlobalISel] Fold xor(cmp(pred, _, _), 1) -> cmp(inverse(pred), _, _)" (and dependent patch "Optimize away a Not feeding a brcond by using tbz instead of tbnz.")"
This reverts commit 8693ddc74371dedc742c9f3d3e4eda1da72c13ea.

Re-committing with the test requiring asserts.
2020-09-01 14:29:04 -07:00
Jordan Rupprecht
8693ddc743 Revert "[GlobalISel] Fold xor(cmp(pred, _, _), 1) -> cmp(inverse(pred), _, _)" (and dependent patch "Optimize away a Not feeding a brcond by using tbz instead of tbnz.")
This reverts commit 8ad8f484b63ca507417b58c9016d2761f2b1a1a8. It causes crashes when running `ninja check-llvm-codegen-aarch64-globalisel`, e.g.
http://lab.llvm.org:8011/builders/clang-with-thin-lto-ubuntu/builds/24132/steps/test-stage1-compiler/logs/stdio.
Note that the crash does not seem to reproduce in debug builds.

5ded4442520d3dbb1aa72e6fe03cddef8828c618 depends on this, so revert that too.
2020-09-01 13:31:57 -07:00
Amara Emerson
8ad8f484b6 [GlobalISel] Fold xor(cmp(pred, _, _), 1) -> cmp(inverse(pred), _, _)
This is needed for an upcoming change to how we translate conditional branches
which might generate these.

Differential Revision: https://reviews.llvm.org/D86383
2020-09-01 10:57:17 -07:00
Matt Arsenault
32a8a10b42 GlobalISel: Implement computeNumSignBits for G_SELECT 2020-09-01 12:50:19 -04:00
Matt Arsenault
35c94d3f7e GlobalISel: Port smarter known bits for umin/umax from DAG 2020-09-01 12:50:15 -04:00
Volkan Keles
061182b7ba GlobalISel: Add combines for extend operations
https://reviews.llvm.org/D86516
2020-09-01 08:50:06 -07:00
Matt Arsenault
9e7e1b2d4b GlobalISel: Implement computeNumSignBits for G_SEXTLOAD/G_ZEXTLOAD 2020-09-01 11:20:02 -04:00
Matt Arsenault
92090e8bd8 GlobalISel: Implement computeKnownBits for G_UNMERGE_VALUES 2020-09-01 11:19:27 -04:00
Matt Arsenault
18bbd9f15e GlobalISel: Artifact combine unmerge of unmerge
Unmerges have the same fundamental problem as G_TRUNC, and G_TRUNC
could be implemented in terms of G_UNMERGE_VALUES. Reducing the number
of elements in unmerge results ends up producing the original unmerge
type profile, so the artifact combiner needs to eliminate the
intermediate illegal registers. This avoids infinite looping in the
legalizer in a future change.

Assuming an unmerge has each result unmerged the same way, this ends
up producing a new unmerge of the source for every definition. I'm not
sure if the artifact combiner should either insert temporary merges
here and erase the original merge, or if the combiner should look at
uses from defs rather than defs from uses for unmerges.

In a few cases this regresses from using 16-bit shifts for 8-bit
values to using 32-bit shifts, but I think these can be legalized
later (the other legalization rules don't try very hard to use 16-bit
shifts either).
2020-09-01 11:01:33 -04:00
Matt Arsenault
1b201914b5 GlobalISel: Combine out redundant sext_inreg
The scalar tests don't work yet, since computeNumSignBits apparently
doesn't handle sextload yet, and sext folds into the load first.
2020-08-28 17:57:31 -04:00
Matt Arsenault
af1c1e20f4 AMDGPU/GlobalISel: Implement computeKnownBits for groupstaticsize 2020-08-27 19:39:44 -04:00
Matt Arsenault
f08bbde83f Correctly revert "GlobalISel: Use & operator on KnownBits"
I mis-resolved the revert through moving the code to another function.
2020-08-27 19:08:31 -04:00
Matt Arsenault
abc99ab572 GlobalISel: Implement known bits for min/max 2020-08-27 16:56:17 -04:00
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
9607ccf626 GlobalISel: Remove leftover lit.local.cfg
The global-isel feature has been required for a long time and was
removed in c9455d3c579292e7ae5b7559ad0302d459e69a95, so this was
causing all tests to be skipped.
2020-08-27 13:49:06 -04:00
Aditya Nandakumar
db464a3dbf [GISel] Add new GISel combiners for G_SELECT
https://reviews.llvm.org/D83833

Patch adds two new GICombinerRules for G_SELECT. The rules include:
combining selects with undef comparisons into their first selectee value,
and to combine away selects with constant comparisons. Patch additionally
adds a new combiner test for the AArch64 target to test these new G_SELECT
combiner rules and the existing select_same_val combiner rule.

Patch by  mkitzan
2020-08-27 09:40:15 -07:00
Matt Arsenault
5207545a86 GlobalISel: IRTranslate minimum of pointer sizes on memcpy
I forgot to squash this with 0b7f6cc71a72a85f8a0cbee836a7a8e31876951a
2020-08-26 20:10:00 -04:00