Commit Graph

632 Commits

Author SHA1 Message Date
Matt Arsenault 1912ace968 AMDGPU: Move handling of AGPR copies to a separate function
This is in preparation for fixing multiple problems with the way AGPR
copies are handled, but this change is NFC itself. First, it's relying
on recursively calling copyPhysReg, which is losing information
necessary to get correct super register handling.

Second, it's constructing a new RegScavenger and doing a O(N^2) walk
on every single sub-spill for every AGPR tuple copy. Third, it's using
the forward form of the scavenger, and not using the preferred
backwards scan.
2020-07-16 14:32:24 -04:00
Matt Arsenault 79f67cae91 AMDGPU: Rename add/sub with carry out instructions
The hardware has created a real mess in the naming for add/sub, which
have been renamed basically every generation. Switch the carry out
pseudos to have the gfx9/gfx10 names. We were using the original SI/CI
v_add_i32/v_sub_i32 names. Later targets reintroduced these names as
carryless instructions with a saturating clamp bit, which we do not
define. Do this rename so we can unambiguously add these missing
instructions.

The carry-in versions should also be renamed, but at least those had a
consistent _u32 name to begin with. The 16-bit instructions were also
renamed, but aren't ambiguous.

This does regress assembler error message quality in some cases. In
mismatched wave32/wave64 situations, this will switch from
"unsupported instruction" to "invalid operand", with the error
pointing at the wrong position. I couldn't quite follow how the
assembler selects these, but the previous behavior seemed accidental
to me. It looked like there was a partial attempt to handle this which
was never completed (i.e. there is an AMDGPUOperand::isBoolReg but it
isn't used for anything).
2020-07-16 13:16:30 -04:00
Matt Arsenault d2e74fad20 AMDGPU: Set more mov flags on V_ACCVGPR_{READ|WRITE}_B32
This fixes extra copies when materializing constants in AGPRs. This
made it a lot harder to trigger the spilling in spill-agpr.ll
2020-07-01 18:58:59 -04:00
Matt Arsenault 14fe4607f1 AMDGPU: Support commuting register and global operand 2020-07-01 13:59:13 -04:00
Matt Arsenault a21544ad11 AMDGPU: Fix handling of target flags when commuting instruction
If the original register operand had a subregister, it wasn't getting
cleared. This resulted in reinterpreted the subreg index as
unrecognized target flags, which produced unparseable MIR.
2020-07-01 13:59:13 -04:00
James Y Knight 4b0aa5724f Change the INLINEASM_BR MachineInstr to be a non-terminating instruction.
Before this instruction supported output values, it fit fairly
naturally as a terminator. However, being a terminator while also
supporting outputs causes some trouble, as the physreg->vreg COPY
operations cannot be in the same block.

Modeling it as a non-terminator allows it to be handled the same way
as invoke is handled already.

Most of the changes here were created by auditing all the existing
users of MachineBasicBlock::isEHPad() and
MachineBasicBlock::hasEHPadSuccessor(), and adding calls to
isInlineAsmBrIndirectTarget or mayHaveInlineAsmBr, as appropriate.

Reviewed By: nickdesaulniers, void

Differential Revision: https://reviews.llvm.org/D79794
2020-07-01 12:51:50 -04:00
Adam Balogh 71c6a36018 [AMDGPU][NFC] Remove redundant condition
Condition `LiteralCount` is checked both in an outer and in an inner
`if` statement in `SIInstrInfo::verifyInstruction()`. This patch removes
the redundant inner check.

The issue was found using `clang-tidy` check under review
`misc-redundant-condition`. See https://reviews.llvm.org/D81272.

Differential Revision: https://reviews.llvm.org/D82555
2020-07-01 09:04:25 +02:00
Piotr Sobczak 0045786f14 [AMDGPU] Select s_cselect
Summary:
Add patterns to select s_cselect in the isel.

Handle more cases of implicit SCC accesses in si-fix-sgpr-copies
to allow new patterns to work.

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, asbirlea, kerbowa, llvm-commits

Tags: #llvm

Re-commit D81925 with a bugfix D82370.

Differential Revision: https://reviews.llvm.org/D81925
Differential Revision: https://reviews.llvm.org/D82370
2020-06-25 10:38:23 +02:00
dstuttar e8775c8d81 [AMDGPU] Make sure to fix implicit operands on insertBranch
Summary:
Without fixImplicitOperands we may end up creating default implicit operands
that are the wrong wave size

Includes simple test that provokes insertBranch in the correct way to expose the
issue being fixed.

Change-Id: I92bdcdee9fcb7b4d91529b84e76a48ac8218483e

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82459
2020-06-24 16:50:48 +01:00
Matt Arsenault 778351df77 Revert "[AMDGPU] Enable compare operations to be selected by divergence"
This reverts commit 521ac0b5ce.

Reported to break thousands of piglit tests.
2020-06-24 11:21:30 -04:00
alex-t 521ac0b5ce [AMDGPU] Enable compare operations to be selected by divergence
Summary: Details: This patch enables SETCC to be selected to S_CMP_* if uniform and V_CMP_* if divergent.

Reviewers: rampitec, arsenm

Reviewed By: rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82194
2020-06-24 11:50:40 +03:00
Your Name cc9d693856 [AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size
Summary:
Make use of both the - (1) clustered bytes and (2) cluster length, to decide on
the max number of mem ops that can be clustered. On an average, when loads
are dword or smaller, consider `5` as max threshold, otherwise `4`. This
heuristic is purely based on different experimentation conducted, and there is
no analytical logic here.

Reviewers: foad, rampitec, arsenm, vpykhtin

Reviewed By: rampitec

Subscribers: llvm-commits, kerbowa, hiraditya, t-tye, Anastasia, tpr, dstuttard, yaxunl, nhaehnle, wdng, jvesely, kzhuravl, thakis

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82393
2020-06-24 00:39:41 +05:30
hsmahesha 5832950adb [AMDGPU/MemOpsCluster] Compute `width` for `MIMG` instruction class.
Summary:
`width` computation is missing for newly added `MIMG`
instruction class. Add it.

Reviewers: foad, rampitec, arsenm

Reviewed By: foad

Subscribers: MatzeB, javed.absar, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81649
2020-06-23 17:32:17 +05:30
Carl Ritson 4a7de36afc [AMDGPU] Avoid use of V_READLANE into EXEC in SGPR spills
Always prefer to clobber input SGPRs and restore them after the
spill.  This applies to both spills to VGPRs and scratch.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D81914
2020-06-20 12:10:47 +09:00
Piotr Sobczak 6d9565d6d5 Revert "[AMDGPU] Select s_cselect"
This caused some failures detected by the buildbot with
expensive checks enabled.

This reverts commit 4067de569f.
2020-06-19 16:41:04 +02:00
Piotr Sobczak 4067de569f [AMDGPU] Select s_cselect
Summary:
Add patterns to select s_cselect in the isel.

Handle more cases of implicit SCC accesses in si-fix-sgpr-copies
to allow new patterns to work.

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, asbirlea, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81925
2020-06-19 16:17:46 +02:00
Matt Arsenault 5f5f566b26 AMDGPU: Don't use 16-bit FP inline constants in integer operands
It seems to be a hardware defect that the half inline constants do not
work as expected for the 16-bit integer operations (the inverse does
work correctly). Experimentation seems to show these are really
reading the 32-bit inline constants, which can be observed by writing
inline asm using op_sel to see what's in the high half of the
constant. Theoretically we could fold the high halves of the 32-bit
constants using op_sel.

The *_asm_all.s MC tests are broken, and I don't know where the script
to autogenerate these are. I started manually fixing it, but there's
just too many cases to fix. This also does break the
assembler/disassembler support for these values, and I'm not sure what
to do about it. These are still valid encodings, so it seems like you
should be able to use them in some way. If you wrote assembly using
them, you could have really meant it (perhaps to read the high bits
with op_sel?). The disassembler will print the invalid literal
constant which will fail to re-assemble. The behavior is also
different depending on the use context. Consider this example, which
was previously accepted and encoded using the inline constant:

  v_mad_i16 v5, v1, -4.0, v3
  ; encoding: [0x05,0x00,0xec,0xd1,0x01,0xef,0x0d,0x04]

In contexts where an inline immediate is required (such as on gfx8/9),
this will now be rejected. For gfx10, this will produce the literal
encoding and change the printed format:
  v_mad_i16 v5, v1, 0xc400, v3
  ; encoding: [0x05,0x00,0x5e,0xd7,0x01,0xff,0x0d,0x04,0x00,0xc4,0x00,0x00]

This is just another variation of the issue that we don't perfectly
handle round trip assembly/disassembly due to not tracking how
immediates were encoded. This doesn't matter much in practice, since
compilers don't emit the suboptimal encoding. I doubt any users are
relying on this behavior (although I did make use of the old behavior
to figure out what was wrong).

Fixes bug 46302.
2020-06-17 19:14:10 -04:00
Matt Arsenault 46579471fd AMDGPU: Fix spill/restore of 192-bit registers
I tried to use an IR inline asm test, but that doesn't work since the
inline asm handling asserts without an MVT to use.
2020-06-14 13:12:01 -04:00
Sebastian Neubauer 29a6ad94fd [AMDGPU] Add G16 support to image instructions
Add G16 feature for GFX10 and support A16 and G16 in GlobalISel.

Differential Revision: https://reviews.llvm.org/D76836
2020-06-12 11:26:31 +02:00
hsmahesha 7410571ce9 Revert "[AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size"
This reverts commit 40a632a335.
2020-06-09 19:27:17 +05:30
hsmahesha 40a632a335 [AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size
Summary:
Make use of both the - (1) clustered bytes and (2) cluster length, to decide on
the max number of mem ops that can be clustered. On an average, when loads
are dword or smaller, consider `5` as max threshold, otherwise `4`. This heuristic
is purely based on different experimentation conducted, and there is no analytical
logic here.

Reviewers: foad, rampitec, arsenm, vpykhtin

Reviewed By: foad, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, Anastasia, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81085
2020-06-09 14:09:14 +05:30
Jay Foad 275ecaae16 [AMDGPU] Cluster MIMG instructions
Differential Revision: https://reviews.llvm.org/D74035
2020-06-08 14:01:53 +01:00
hsmahesha 29c17ed96e [AMDGPU/MemOpsCluster] Code clean-up around accessing of memory operand width
Summary:
Clean-up the width computing logic given a memory operand, and re-arrange code to avoid
code duplication.

Reviewers: foad, rampitec, arsenm, vpykhtin, javedabsar

Reviewed By: foad

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80946
2020-06-03 14:03:52 +05:30
Matt Arsenault 452e0d9023 AMDGPU: Don't run mode switches with exec 0
These are scalar instructions that change vector instructions, so they
should not be executed without any active lanes.

The implementation of -amdgpu-skip-threshold also seem to be backwards
from expected, since decreasing it prevents removal.
2020-06-02 13:47:48 -04:00
hsmahesha 0ed2c04636 [AMDGPU/MemOpsCluster] Let mem ops clustering logic also consider number of clustered bytes
Summary:
While clustering mem ops, AMDGPU target needs to consider number of clustered bytes
to decide on max number of mem ops that can be clustered. This patch adds support to pass
number of clustered bytes to target mem ops clustering logic.

Reviewers: foad, rampitec, arsenm, vpykhtin, javedabsar

Reviewed By: foad

Subscribers: MatzeB, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, javed.absar, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80545
2020-06-01 22:52:34 +05:30
Matt Arsenault f012c58abd AMDGPU: Move MIMG MMO check to verifier 2020-05-29 20:58:23 -04:00
Matt Arsenault 1a9e0d7092 AMDGPU: Make S_DENORM_MODE not be a scheduling boundary
Now that the mode register uses/defs should be properly modeled, we
don't need to treat the FP mode switch as an arbitrary side effect.
2020-05-28 10:39:33 -04:00
Stanislav Mekhanoshin 7392bbc301 AMDGPU/GlobalISel: Fixed insert element for non-standard vectors
Differential Revision: https://reviews.llvm.org/D80653
2020-05-27 16:26:22 -07:00
alex-t eb1092ada3 [AMDGPU] Fix for the lost CarryOut/CarryIn register operands in S_ADD/SUB_CO_PSEUDO.
Summary: This fixes the 5b898bddff bug when the carry-in and carry-out registers became lost in lowering S_ADD/SUB_CO_PSEUDO.

Reviewers: rampitec, arsenm

Reviewed By: arsenm

Subscribers: msearles, arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80158
2020-05-27 22:41:04 +03:00
Matt Arsenault d37ce53ad3 AMDGPU: Set StackPointerRegisterToSaveRestore
This will enable selecting non-entry block allocas. Skip the SP write
check in the base isSchedulingBoundary implementation to preserve the
previous scheduling behavior and avoid test churn. It's apparently for
compile time reasons, but if we were to use this more work would be
needed since in some of the failing tests, we seem to incorrectly get
hazard nops inserted.
2020-05-27 13:44:05 -04:00
Matt Arsenault 07cd19efa2 AMDGPU: Fix dropping MI flags when rewriting instructions
All 3 passes that change instruction encodings were dropping MI
flags. This avoids scheduling regressions caused by setting
mayRaiseFPExceptions on FP instructions for non-strictfp functions.
2020-05-27 13:27:06 -04:00
Matt Arsenault 833996cef1 AMDGPU: Fix backwards s_cselect_* operands
The vector equivalent has backwards operands, but the scalar version
does not. The passes that use these hooks aren't enabled by default,
so this doesn't really change anything.
2020-05-27 09:26:09 -04:00
David Blaikie 025cd300cd Collapse variable into assert to remove non-assert unused variable 2020-05-05 11:04:43 -07:00
Stanislav Mekhanoshin 9ef166e657 [AMDGPU] Fix FoldImmediate for 16 bit operand
Differential Revision: https://reviews.llvm.org/D79362
2020-05-05 10:19:14 -07:00
Stanislav Mekhanoshin c85eda74b8 [AMDGPU] fix copies between 32 and 16 bit
This a hack to fix illegal 32 to 16 bit copies.
The problem is when we make 16 bit subregs legal it creates
a huge amount of failures which can only be resolved at once
without a temporary hack like this.

The next step is to change operands, instruction definitions
and patterns until this hack is not needed.

Differential Revision: https://reviews.llvm.org/D79119
2020-05-04 08:54:22 -07:00
alex-t 5b898bddff [AMDGPU] Enable carry out ADD/SUB operations divergence driven instruction selection.
Summary: This change enables all kind of carry out ISD opcodes to be selected according to the node divergence.

Reviewers: rampitec, arsenm, vpykhtin

Reviewed By: rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78091
2020-05-04 16:42:25 +03:00
Stanislav Mekhanoshin 26777ad7a0 [AMDGPU] Adapt GCNRegBankReassign for 16 bit subregs
It allows it not to crash and analyze 16 bit subregs if those
appear in the instructions. At the same time it does not attempt
to reassign these. It still can correctly identify register
banks to let larger registers to be reassigned.

More work will be needed here when real instructions will use
these registers and more tests as well.

Differential Revision: https://reviews.llvm.org/D78772
2020-04-28 16:16:04 -07:00
Stanislav Mekhanoshin 8a30460697 [AMDGPU] Define AGPR subregs
These are only needed as VGPR counterpart.

Differential Revision: https://reviews.llvm.org/D78597
2020-04-28 15:30:43 -07:00
Stanislav Mekhanoshin 46a75436f8 [AMDGPU] Define special SGPR subregs
These are used in SReg_32 and when we start to use SGPR_LO16
there will be compaints that not all registers in RC support
all subreg indexes. For now it is NFC.

Unused regunits are reserved so that verifier does not complain
about missing phys reg live-ins.

Differential Revision: https://reviews.llvm.org/D78591
2020-04-28 14:57:46 -07:00
Stanislav Mekhanoshin 395d93358e Revert "[AMDGPU] Define special SGPR subregs"
This reverts commit 1baaa080e0.
2020-04-28 13:53:15 -07:00
Stanislav Mekhanoshin 1baaa080e0 [AMDGPU] Define special SGPR subregs
These are used in SReg_32 and when we start to use SGPR_LO16
there will be compaints that not all registers in RC support
all subreg indexes. For now it is NFC.

Unused regunits are reserved so that verifier does not complain
about missing phys reg live-ins.

Differential Revision: https://reviews.llvm.org/D78591
2020-04-28 13:34:24 -07:00
Stanislav Mekhanoshin 992fbce4e9 [AMDGPU] copyPhysReg() for 16 bit SGPR subregs
Differential Revision: https://reviews.llvm.org/D78255
2020-04-17 11:59:39 -07:00
Stanislav Mekhanoshin fde2aefa22 [AMDGPU] Use SDWA for 16 bit subreg copy
This simplifies the logic and allows to use it on GFX8.

Differential Revision: https://reviews.llvm.org/D78150
2020-04-17 11:45:44 -07:00
Michael Liao b54b4ecac3 Fix `-Wextra` warning. NFC. 2020-04-10 03:22:02 -04:00
Stanislav Mekhanoshin 96e51ed005 [AMDGPU] Implement copyPhysReg for 16 bit subregs
Differential Revision: https://reviews.llvm.org/D74937
2020-04-07 14:22:46 -07:00
Matt Arsenault 30ebafaa56 CodeGen: Convert some TII hooks to use Register 2020-04-03 14:52:54 -04:00
Matt Arsenault 178050c3ba AMDGPU: Use Register in more places 2020-04-03 14:52:54 -04:00
Guillaume Chatelet c9d5c19597 [Alignment][NFC] Transitionning more getMachineMemOperand call sites
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, jrtc27, atanasyan, Jim, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77121
2020-03-31 08:36:18 +00:00
David Stuttard a74b33f612 AMDGPU: Fix SMRD test in trivially disjoint mem access code
Summary:
This seems like an obvious error - cut and paste issue?
The change does make a change to one of the lit tests - it stops s_buffer_load
re-ordering past an MUBUF instruction (which is not surprising).

Change-Id: I80be99de5b62af4f42e91af2591b76a52ac9efa6

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75686
2020-03-05 17:14:01 +00:00
Sander de Smalen 8fbc925807 Add OffsetIsScalable to getMemOperandWithOffset
Summary:
Making `Scale` a `TypeSize` in AArch64InstrInfo::getMemOpInfo,
has the effect that all places where this information is used
(notably, TargetInstrInfo::getMemOperandWithOffset) will need
to consider Scale - and derived, Offset - possibly being scalable.

This patch adds a new operand `bool &OffsetIsScalable` to
TargetInstrInfo::getMemOperandWithOffset and fixes up all
the places where this function is used, to consider the
offset possibly being scalable.

In most cases, this means bailing out because the algorithm does not
(or cannot) support scalable offsets in places where it does some
form of alias checking for example.

Reviewers: rovka, efriedma, kristof.beyls

Reviewed By: efriedma

Subscribers: wuzish, kerbowa, MatzeB, arsenm, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, javed.absar, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72758
2020-02-18 15:53:29 +00:00
Sebastian Neubauer 8756869170 [AMDGPU] Add a16 feature to gfx10
Based on D72931

This adds a new feature called A16 which is enabled for gfx10.
gfx9 keeps the R128A16 feature so it can share all the instruction encodings
with gfx7/8.

Differential Revision: https://reviews.llvm.org/D73956
2020-02-10 09:04:23 +01:00
Stanislav Mekhanoshin cacc3b7a55 [AMDGPU] Cleanup assumptions about generated subregs
We are using countPopulation on a LaneBitmask to determine
a number of registers it covers. This is the assumption which
does not necessarily need to be true. It is not changed but
factored into a single call SIRegisterInfo::getNumCoveredRegs().

Some other places are cleaned up with respect to assumptions
about subreg indexes values and tablegen behavior.

Differential Revision: https://reviews.llvm.org/D74177
2020-02-06 17:39:24 -08:00
Jay Foad 2252cac694 [ANDGPU] getMemOperandsWithOffset: support BUF non-stack-access instructions with resource but no vaddr
Summary:
This enables clustering for many more BUF instructions.

Reviewers: rampitec, arsenm, nhaehnle

Subscribers: jvesely, wdng, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73868
2020-02-03 22:49:30 +00:00
Jay Foad 05297b7cbe [AMDGPU] getMemOperandsWithOffset: add resource operand for BUF instructions
Summary:
This prevents unwanted clustering of BUF instructions with the same
vaddr but different resource descriptors.

Reviewers: rampitec, arsenm, nhaehnle

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73867
2020-02-03 17:06:09 +00:00
Simon Moll 5c8ba508b2 [NFC] unsigned->Register in storeRegTo/loadRegFromStack
Summary:
This patch makes progress on the 'unsigned -> Register' rewrite for
`TargetInstrInfo::loadRegFromStack` and `TII::storeRegToStack`.

Reviewers: arsenm, craig.topper, uweigand, jpienaar, atanasyan, venkatra, robertlytton, dylanmckay, t.p.northover, kparzysz, tstellar, k-ishizaka

Reviewed By: arsenm

Subscribers: wuzish, merge_guards_bot, jyknight, sdardis, nemanjai, jvesely, wdng, nhaehnle, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73870
2020-02-03 14:22:16 +01:00
Jay Foad d07a789579 [AMDGPU] Cluster FLAT instructions with both vaddr and saddr
Reviewers: rampitec, arsenm

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73634
2020-01-29 17:01:35 +00:00
Stanislav Mekhanoshin c2ad7ee1a9 [AMDGPU] override isHighLatencyDef
SIMachineScheduler uses isHighLatencyInstruction with the same
sematincs, but TargetInstrInfo has virtual isHighLatencyDef
method, so override it instead.

Added FLAT to the list of high latency opcodes and a check for
mayLoad since stores are not technically high latency in terms
of data dependency.

This change did not produce any visible impact on our tests.

Differential Revision: https://reviews.llvm.org/D73582
2020-01-29 08:01:29 -08:00
Jay Foad ad08c01d6c [AMDGPU] Simplify DS and SM cases in getMemOperandsWithOffset
Summary:
This removes a couple of unnecessary isReg checks, now that
memOpsHaveSameBasePtr can handle FI operands, but is otherwise NFC.

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73485
2020-01-29 09:43:24 +00:00
Jay Foad 1bf00219fc [AMDGPU] Handle multiple base operands in areMemAccessesTriviallyDisjoint
Summary:
This is in preparation for getMemOperandsWithOffset returning more base
operands.

Depends on D73455.

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73456
2020-01-27 14:45:21 +00:00
Jay Foad 6461eadf8f [AMDGPU] Handle multiple base operands in shouldClusterMemOps
Summary:
This is in preparation for getMemOperandsWithOffset returning more base
operands.

Depends on D73454.

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73455
2020-01-27 14:45:21 +00:00
Jay Foad fcf5254fa7 [AMDGPU] Handle frame index base operands in memOpsHaveSameBasePtr
Summary:
This is in preparation for getMemOperandsWithOffset returning more base
operands.

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, arphaman, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73454
2020-01-27 14:45:21 +00:00
Stanislav Mekhanoshin be8e38cbd9 Correct NumLoads in clustering
Scheduler sends NumLoads argument into shouldClusterMemOps()
one less the actual cluster length. So for 2 instructions
it will pass just 1. Correct this number.

This is NFC for in tree targets.

Differential Revision: https://reviews.llvm.org/D73292
2020-01-24 12:45:28 -08:00
Stanislav Mekhanoshin 555d8f4ef5 [AMDGPU] Bundle loads before post-RA scheduler
We are relying on atrificial DAG edges inserted by the
MemOpClusterMutation to keep loads and stores together in the
post-RA scheduler. This does not work all the time since it
allows to schedule a completely independent instruction in the
middle of the cluster.

Removed the DAG mutation and added pass to bundle already
clustered instructions. These bundles are unpacked before the
memory legalizer because it does not work with bundles but also
because it allows to insert waitcounts in the middle of a store
cluster.

Removing artificial edges also allows a more relaxed scheduling.

Differential Revision: https://reviews.llvm.org/D72737
2020-01-24 11:33:38 -08:00
Matt Arsenault d1dbb5e471 AMDGPU/GlobalISel: Select G_INSERT_VECTOR_ELT 2020-01-22 11:00:49 -05:00
Jay Foad e0f0d0e55c [MachineScheduler] Allow clustering mem ops with complex addresses
The generic BaseMemOpClusterMutation calls into TargetInstrInfo to
analyze the address of each load/store instruction, and again to decide
whether two instructions should be clustered. Previously this had to
represent each address as a single base operand plus a constant byte
offset. This patch extends it to support any number of base operands.

The old target hook getMemOperandWithOffset is now a convenience
function for callers that are only prepared to handle a single base
operand. It calls the new more general target hook
getMemOperandsWithOffset.

The only requirements for the base operands returned by
getMemOperandsWithOffset are:
- they can be sorted by MemOpInfo::Compare, such that clusterable ops
  get sorted next to each other, and
- shouldClusterMemOps knows what they mean.

One simple follow-on is to enable clustering of AMDGPU FLAT instructions
with both vaddr and saddr (base register + offset register). I've left
a FIXME in the code for this case.

Differential Revision: https://reviews.llvm.org/D71655
2020-01-22 14:28:24 +00:00
Amara Emerson 67a8775322 [AArch64] Don't generate gpr CSEL instructions in early-ifcvt if regclasses aren't compatible.
In GlobalISel we may in some unfortunate circumstances generate PHIs with
operands that are on separate banks. If-conversion doesn't currently check for
that case and ends up generating a CSEL on AArch64 with incorrect register
operands.

Differential Revision: https://reviews.llvm.org/D72961
2020-01-21 16:51:31 -08:00
Matt Arsenault 8615eeb455 AMDGPU: Partially merge indirect register write handling
a785209bc2 switched to using a pseudos instead of manually tying
operands on the regular instruction. The VGPR indexing mode path
should have the same problems that change attempted to avoid, so these
should use the same strategy.

Use a single pseudo for the VGPR indexing mode and movreld paths, and
expand it based on the subtarget later. These have essentially the
same constraints, reading the index from m0.

Switch from using an offset to the subregister index directly, instead
of computing an offset and re-adding it back. Also add missing pseudos
for existing register class sizes.
2020-01-20 17:19:16 -05:00
Stanislav Mekhanoshin eca4474587 [AMDGPU] Fix getInstrLatency() always returning 1
We do not have InstrItinerary so generic getInstLatency() was always
defaulting to return 1 cycle. We need to use TargetSchedModel instead
to compute an instruction's latency.

Differential Revision: https://reviews.llvm.org/D72655
2020-01-14 01:08:30 -08:00
Stanislav Mekhanoshin cd69e4c74c [AMDGPU] Fix bundle scheduling
Bundles coming to scheduler considered free, i.e. zero latency.
Fixed.

Differential Revision: https://reviews.llvm.org/D72487
2020-01-09 15:56:36 -08:00
Matt Arsenault e29ae3799b TII: Fix using Register for a subregister index argument 2019-12-27 16:53:29 -05:00
Matt Arsenault a37e958558 AMDGPU: Use correct DebugLoc 2019-12-27 08:49:43 -05:00
Jay Foad c5c935ab66 Make more use of MachineInstr::mayLoadOrStore. 2019-12-19 11:51:52 +00:00
Jay Foad 0412f518dc [AMDGPU] Fix typo in SIInstrInfo::memOpsHaveSameBasePtr
Summary:
The typo has been present since memOpsHaveSameBasePtr was introduced in
r313208.

It caused SIInstrInfo::shouldClusterMemOps to cluster more mem ops than
it was supposed to.

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71616
2019-12-17 18:54:27 +00:00
Kristof Beyls 870f39d310 Fix assertion failure in getMemOperandWithOffsetWidth
This fixes an assertion failure that triggers inside
getMemOperandWithOffset when Machine Sinking calls it on a MachineInstr
that is not a memory operation.

Different backends implement getMemOperandWithOffset differently: some
return false on non-memory MachineInstrs, others assert.

The Machine Sinking pass in at least SinkingPreventsImplicitNullCheck
relies on getMemOperandWithOffset to return false on non-memory
MachineInstrs, instead of asserting.

This patch updates the documentation on getMemOperandWithOffset that it
should return false on any MachineInstr it cannot handle, instead of
asserting. It also adapts the in-tree backends accordingly where
necessary.

Differential Revision: https://reviews.llvm.org/D71359
2019-12-17 10:56:09 +00:00
Austin Kerbow 256ad954a9 AMDGPU: Reuse carry out register during FI elimination
Summary:
Pre gfx9 we need to scavenge a 64-bit SGPR to use as the carry out for an Add.
If only one SGPR was available this crashed when trying to scavenge another
32bit SGPR to materialize the offset.

Instead, reuse a 32-bit SGPR from the carry out as the offset register.

Also prefer to use vcc for the unused carry out when it is available.

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70614
2019-11-28 10:13:48 -08:00
Dmitry Preobrazhensky 6778a62eb0 [AMDGPU][GFX10] Disabled v_movrel*[sdwa|dpp] opcodes in codegen
These opcodes use indirect register addressing so they need special handling by codegen (currently missing).

Reviewers: vpykhtin, arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D70400
2019-11-20 17:57:50 +03:00
Matt Arsenault 31479d868e AMDGPU: Change boolean content type to 0 or 1
The usage of target boolean checks is overly inflexible, since sext
and zext of a compare are equally cheap. The choice is arbitrary, but
using 0/1 to some degree is the choice of lower resistance since
that's what most targets use. This enables a few combines that don't
bother to support ZeroOrNegativeOneBooleanContent.
2019-11-15 13:43:47 +05:30
Matt Arsenault e6c9a9af39 Use MCRegister in copyPhysReg 2019-11-11 14:42:33 +05:30
Matt Arsenault d9e0a2942a AMDGPU: Disallow spill folding with m0 copies
readlane and writelane instructions are not allowed to use m0 as the
data operand, so spilling them is tricky and would require an
intermediate SGPR to spill it. Constrain the virtual register class in
this caes to disallow the inline spiller from folding the m0 operand
directly into the spill instruction.

I copied this hack from AArch64 which has the same problem for $sp.
2019-10-30 14:56:33 -07:00
Stanislav Mekhanoshin 4c0251da14 [AMDGPU] Enable SGPR copy folding
That used to fail in the last testcase function because after
%0:sreg_64.sub0 was folded into %3:sreg_32_xm0_xexec COPY, it
was further folded into S_STORE_DWORD_IMM. Its legal effective
subreg class is SReg_32 while instruction expects more restricted
SReg_32_XM0_EXEC. However, SIInstrInfo::isLegalRegOperand()
passed the legality check and it was caught in the verifier.

Borrowed code from the verifier to check for RC legality.

Differential Revision: https://reviews.llvm.org/D69445
2019-10-25 15:08:30 -07:00
Changpeng Fang 1ce552f3ef AMDGPU: Fix the broken dominator tree when creating waterfall loop for resource descriptor
Summary:
  In loadSRsrcFromVGPR, if MBB is the same as Succ, Remiander is not the immediate dominator of Succ.

Reviewer:
  arsenm

Differential Revision:
  https://reviews.llvm.org/D69358
2019-10-25 13:08:04 -07:00
Matt Arsenault dd6cf159ba AMDGPU: Stop adding m0 implicit def to SGPR spills
r375293 removed the SGPR spilling with scalar stores path, so this is
no longer necessary. This also always had the defect of adding the def
even when this path wasn't in use.

llvm-svn: 375448
2019-10-21 19:42:29 +00:00
Stanislav Mekhanoshin 33092194f2 [AMDGPU] Select AGPR in PHI operand legalization
If a PHI defines AGPR legalize its operands to AGPR.
At the moment we can get an AGPR PHI with VGPR operands.
I am not aware of any problems as it seems to be handled
gracefully in RA, but this is not right anyway.

It also slightly decreases VGPR pressure in some cases
because we do not have to a copy via VGPR.

Differential Revision: https://reviews.llvm.org/D69206

llvm-svn: 375446
2019-10-21 19:25:27 +00:00
Matt Arsenault 7cd57dcd5b AMDGPU: Split flat offsets that don't fit in DAG
We handle it this way for some other address spaces.

Since r349196, SILoadStoreOptimizer has been trying to do this. This
is after SIFoldOperands runs, which can change the addressing
patterns. It's simpler to just split this earlier.

llvm-svn: 375366
2019-10-20 17:34:44 +00:00
Matt Arsenault f9a42ed0a7 AMDGPU: Relax 32-bit SGPR register class
Mostly use SReg_32 instead of SReg_32_XM0 for arbitrary values. This
will allow the register coalescer to do a better job eliminating
copies to m0.

For GlobalISel, as a terrible hack, use SGPR_32 for things that should
use SCC until booleans are solved.

llvm-svn: 375267
2019-10-18 18:26:37 +00:00
David Stuttard 2d6a2303f8 [AMDGPU] Fix-up cases where writelane has 2 SGPR operands
Summary:
Even though writelane doesn't have the same constraints as other valu
instructions it still can't violate the >1 SGPR operand constraint

Due to later register propagation (e.g. fixing up vgpr operands via
readfirstlane) changing writelane to only have a single SGPR is tricky.

This implementation puts a new check after SIFixSGPRCopies that prevents
multiple SGPRs being used in any writelane instructions.

The algorithm used is to check for trivial copy prop of suitable constants into
one of the SGPR operands and perform that if possible. If this isn't possible
put an explicit copy of Src1 SGPR into M0 and use that instead (this is
allowable for writelane as the constraint is for SGPR read-port and not
constant-bus access).

Reviewers: rampitec, tpr, arsenm, nhaehnle

Reviewed By: rampitec, arsenm, nhaehnle

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, mgorny, yaxunl, tpr, t-tye, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D51932

Change-Id: Ic7553fa57440f208d4dbc4794fc24345d7e0e9ea
llvm-svn: 375004
2019-10-16 14:37:39 +00:00
Austin Kerbow 527e9f9a3f AMDGPU: Fix infinite searches in SIFixSGPRCopies
Summary:
Two conditions could lead to infinite loops when processing PHI nodes in
SIFixSGPRCopies.

The first condition involves a REG_SEQUENCE that uses registers defined by both
a PHI and a COPY.

The second condition arises when a physical register is copied to a virtual
register which is then used in a PHI node. If the same virtual register is
copied to the same physical register, the result is an endless loop.

%0:sgpr_64 = COPY $sgpr0_sgpr1
%2 = PHI %0, %bb.0, %1, %bb.1
$sgpr0_sgpr1 = COPY %0

Reviewers: alex-t, rampitec, arsenm

Reviewed By: rampitec

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68970

llvm-svn: 374944
2019-10-15 19:59:45 +00:00
Stanislav Mekhanoshin 1184c27fa5 [AMDGPU] Support mov dpp with 64 bit operands
We define mov/update dpp intrinsics as overloaded but do not
support i64, which is a practically useful type. Fix the
selection and lowering.

Differential Revision: https://reviews.llvm.org/D68673

llvm-svn: 374910
2019-10-15 16:41:15 +00:00
Alexander Timofeev c4d256a590 [AMDGPU] Come back patch for the 'Assign register class for cross block values according to the divergence.'
Detailed description:

    After https://reviews.llvm.org/D59990 submit several issues were discovered.
    Changes in common code were preserved but AMDGPU specific part was reverted to keep the backend working correctly.

    Discovered issues were addressed in the following commits:

    https://reviews.llvm.org/D67662
    https://reviews.llvm.org/D67101
    https://reviews.llvm.org/D63953
    https://reviews.llvm.org/D63731

    This change brings back AMDGPU specific changes.

  Reviewed by: rampitec, arsenm

  Differential Revision: https://reviews.llvm.org/D68635

llvm-svn: 374767
2019-10-14 12:01:10 +00:00
Matt Arsenault 12994a70cf AMDGPU: Use SGPR_128 instead of SReg_128 for vregs
SGPR_128 only includes the real allocatable SGPRs, and SReg_128 adds
the additional non-allocatable TTMP registers. There's no point in
allocating SReg_128 vregs. This shrinks the size of the classes
regalloc needs to consider, which is usually good.

llvm-svn: 374284
2019-10-10 07:11:33 +00:00
Matt Arsenault 27269054d2 GlobalISel: Add target pre-isel instructions
Allows targets to introduce regbankselectable
pseudo-instructions. Currently the closet feature to this is an
intrinsic. However this requires creating a public intrinsic
declaration. This litters the public intrinsic namespace with
operations we don't necessarily want to expose to IR producers, and
would rather leave as private to the backend.

Use a new instruction bit. A previous attempt tried to keep using enum
value ranges, but it turned into a mess.

llvm-svn: 373937
2019-10-07 18:43:29 +00:00
Stanislav Mekhanoshin 1384c3a5b8 [AMDGPU] Fix illegal agpr use by VALU
When SIFixSGPRCopies attempts to fix an illegal copy from vector to
scalar register it calls moveToVALU(). A copy from an agpr to sgpr
becomes a copy from agpr to agpr, which may result in the illegal
register class at a use of this copy.

Solution is to copy it always into a vgpr. This may result in a
subsequent copy into an agpr if that is what really needed, however
should not happen too often and likely will be folded later.

The opposite situation may not happen because an sgpr is always
illegal where agpr is legal, so such user instructions may not
exist.

Differential Revision: https://reviews.llvm.org/D68358

llvm-svn: 373544
2019-10-02 23:23:46 +00:00
Piotr Sobczak 265e94e657 [AMDGPU] Extend buffer intrinsics with swizzling
Summary:
Extend cachepolicy operand in the new VMEM buffer intrinsics
to supply information whether the buffer data is swizzled.
Also, propagate this information to MIR.

Intrinsics updated:
int_amdgcn_raw_buffer_load
int_amdgcn_raw_buffer_load_format
int_amdgcn_raw_buffer_store
int_amdgcn_raw_buffer_store_format
int_amdgcn_raw_tbuffer_load
int_amdgcn_raw_tbuffer_store
int_amdgcn_struct_buffer_load
int_amdgcn_struct_buffer_load_format
int_amdgcn_struct_buffer_store
int_amdgcn_struct_buffer_store_format
int_amdgcn_struct_tbuffer_load
int_amdgcn_struct_tbuffer_store

Furthermore, disable merging of VMEM buffer instructions
in SI Load/Store optimizer, if the "swizzled" bit on the instruction
is on.

The default value of the bit is 0, meaning that data in buffer
is linear and buffer instructions can be merged.

There is no difference in the generated code with this commit.
However, in the future it will be expected that front-ends
use buffer intrinsics with correct "swizzled" bit set.

Reviewers: arsenm, nhaehnle, tpr

Reviewed By: nhaehnle

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, arphaman, jfb, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68200

llvm-svn: 373491
2019-10-02 17:22:36 +00:00
Changpeng Fang f5524f0451 Remove the AliasAnalysis argument in function areMemAccessesTriviallyDisjoint
Reviewers:
  arsenm

Differential Revision:
  https://reviews.llvm.org/D58360

llvm-svn: 373024
2019-09-26 22:53:44 +00:00
Simon Pilgrim 5f2d8b2618 [TargetInstrInfo] Let findCommutedOpIndices take const MachineInstr&
Neither the base implementation of findCommutedOpIndices nor any in-tree target modifies the instruction passed in and there is no reason why they would in the future.

Committed on behalf of @hvdijk (Harald van Dijk)

Differential Revision: https://reviews.llvm.org/D66138

llvm-svn: 372882
2019-09-25 14:55:57 +00:00
Alexander Timofeev 6524a7a2b9 [AMDGPU]: PHI Elimination hooks added for custom COPY insertion. Fixed
Defferential Revision: https://reviews.llvm.org/D67101

Reviewers: rampitec, vpykhtin
llvm-svn: 372086
2019-09-17 09:08:58 +00:00
Alexander Timofeev 9ff70132bf Revert for: [AMDGPU]: PHI Elimination hooks added for custom COPY insertion.
llvm-svn: 371873
2019-09-13 17:37:30 +00:00
Matt Arsenault 8382ce5f1b AMDGPU: Inline constant when materalizing FI with add on gfx9
This was relying on the SGPR usable for the carry out clobber to also
be used for the input. There was no carry out on gfx9. With no carry
out clobber to worry about, so the literal can just be directly used
with a VOP2 add.

llvm-svn: 371791
2019-09-12 23:46:46 +00:00
Michael Liao 7957d4c015 [AMDGPU] Fix crash in phi-elimination hook.
Summary: - Pre-check in case there's just a single PHI insn.

Reviewers: alex-t, rampitec, arsenm

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, dstuttard, tpr, t-tye, hiraditya, llvm-commits, yaxunl

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67451

llvm-svn: 371649
2019-09-11 19:55:20 +00:00
Alexander Timofeev c2d292f839 [AMDGPU]: PHI Elimination hooks added for custom COPY insertion.
Reviewers: rampitec, vpykhtin

  Differential Revision: https://reviews.llvm.org/D67101

llvm-svn: 371508
2019-09-10 10:58:57 +00:00
Matt Arsenault 60c8b8bcf2 AMDGPU: Allow getMemOperandWithOffset to analyze stack accesses
Report soffset as a base register if the scratch resource can be
ignored.

llvm-svn: 371149
2019-09-05 23:54:35 +00:00
Matt Arsenault 84489b34f6 AMDGPU: Handle frame index expansion with no free SGPRs pre gfx9
Since an add instruction must produce an unused carry out, this
requires additional SGPRs. This can be avoided by keeping the entire
offset computation in SGPRs. If one SGPR is still available, this only
costs one extra mov. If none are available, the entire computation can
be done in place and reversed.

This does assume the use is a VGPR operand. This was already assumed,
and we currently only select frame indexes to VALU instructions. This
should probably be fixed at some point to handle more possible MIR.

llvm-svn: 370929
2019-09-04 17:12:57 +00:00
Matt Arsenault 216d8ff60b AMDGPU: Don't use frame virtual registers
SGPR spills aren't really handled after SILowerSGPRSpills. In order to
directly control what happens if the scavenger needs to spill, the
scavenger needs to be used directly. There is an alternative to
spilling in these contexts anyway since the frame register can be
increment and restored.

This does present another possible issue if spilling is needed for the
unused carry out if an add is needed. I think this can be avoided by
using a scalar add (although that clobbers SCC, which happens anyway).

llvm-svn: 370281
2019-08-29 01:13:47 +00:00
Stanislav Mekhanoshin e6e1c4eac0 [AMDGPU] w/a for gfx908 mfma SrcC literal HW bug
gfx908 ignores an mfma if SrcC is a literal.

Differential Revision: https://reviews.llvm.org/D66670

llvm-svn: 369818
2019-08-23 22:22:29 +00:00
Alexander Timofeev 78347c979e [AMDGPU] Prevent VGPR copies from moving across the EXEC mask definitions
Differential Revision: https://reviews.llvm.org/D63731
Reviewers: qcolombet, rampitec

llvm-svn: 369532
2019-08-21 15:15:04 +00:00
Matt Arsenault 4b7fc85c0b Revert "AMDGPU: Fix iterator error when lowering SI_END_CF"
This reverts r367500 and r369203. This is causing various test
failures.

llvm-svn: 369417
2019-08-20 17:45:25 +00:00
Daniel Sanders 0c47611131 Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM
Summary:
This clang-tidy check is looking for unsigned integer variables whose initializer
starts with an implicit cast from llvm::Register and changes the type of the
variable to llvm::Register (dropping the llvm:: where possible).

Partial reverts in:
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
X86FixupLEAs.cpp - Some functions return unsigned and arguably should be MCRegister
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
HexagonBitSimplify.cpp - Function takes BitTracker::RegisterRef which appears to be unsigned&
MachineVerifier.cpp - Ambiguous operator==() given MCRegister and const Register
PPCFastISel.cpp - No Register::operator-=()
PeepholeOptimizer.cpp - TargetInstrInfo::optimizeLoadInstr() takes an unsigned&
MachineTraceMetrics.cpp - MachineTraceMetrics lacks a suitable constructor

Manual fixups in:
ARMFastISel.cpp - ARMEmitLoad() now takes a Register& instead of unsigned&
HexagonSplitDouble.cpp - Ternary operator was ambiguous between unsigned/Register
HexagonConstExtenders.cpp - Has a local class named Register, used llvm::Register instead of Register.
PPCFastISel.cpp - PPCEmitLoad() now takes a Register& instead of unsigned&

Depends on D65919

Reviewers: arsenm, bogner, craig.topper, RKSimon

Reviewed By: arsenm

Subscribers: RKSimon, craig.topper, lenary, aemerson, wuzish, jholewinski, MatzeB, qcolombet, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, wdng, nhaehnle, sbc100, jgravelle-google, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, javed.absar, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, tpr, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, Jim, s.egerton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65962

llvm-svn: 369041
2019-08-15 19:22:08 +00:00
Austin Kerbow a05c384132 Re-commit: [AMDGPU] Use S_DENORM_MODE for gfx10
Summary: During fdiv32 lowering use S_DENORM_MODE to select denorm mode in gfx10.

Reviewers: arsenm, rampitec

Reviewed By: arsenm, rampitec

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65620

llvm-svn: 367969
2019-08-06 02:16:11 +00:00
Dmitri Gribenko 37aa8ad663 Revert "[AMDGPU] Use S_DENORM_MODE for gfx10"
This reverts commit r367882. It broke the test
MC/Disassembler/AMDGPU/gfx10_dasm_all.txt.

llvm-svn: 367904
2019-08-05 18:36:43 +00:00
Austin Kerbow 8d229dbb47 [AMDGPU] Use S_DENORM_MODE for gfx10
Summary: During fdiv32 lowering use S_DENORM_MODE to select denorm mode in gfx10.

Reviewers: arsenm, rampitec

Reviewed By: arsenm, rampitec

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65620

llvm-svn: 367882
2019-08-05 16:09:49 +00:00
Daniel Sanders 2bea69bf65 Finish moving TargetRegisterInfo::isVirtualRegister() and friends to llvm::Register as started by r367614. NFC
llvm-svn: 367633
2019-08-01 23:27:28 +00:00
Matt Arsenault d48324ff6f Reapply "AMDGPU: Split block for si_end_cf"
This reverts commit r359363, reapplying r357634

llvm-svn: 367500
2019-08-01 01:25:27 +00:00
Jay Foad 3bdcedbf3d [AMDGPU] Fix typo in error message
llvm-svn: 367235
2019-07-29 16:17:13 +00:00
Carl Ritson 00e89b428b [AMDGPU] Add llvm.amdgcn.softwqm intrinsic
Add llvm.amdgcn.softwqm intrinsic which behaves like llvm.amdgcn.wqm
only if there is other WQM computation in the shader.

Reviewers: nhaehnle, tpr

Reviewed By: nhaehnle

Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, t-tye, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64935

llvm-svn: 367097
2019-07-26 09:54:12 +00:00
Matt Arsenault 85f3890126 AMDGPU: Force s_waitcnt after GWS instructions
This is apparently required to be the immediately following
instruction, so force it into a bundle with a waitcnt.

llvm-svn: 366607
2019-07-19 19:47:30 +00:00
Matt Arsenault 35c96598b1 AMDGPU/GlobalISel: Select flat loads
Now that the patterns use the new PatFrag address space support, the
only blocker to importing most load patterns is the addressing mode
complex patterns.

llvm-svn: 366237
2019-07-16 18:05:29 +00:00
Jay Foad 27ec195f39 [AMDGPU] Fix DPP combiner check for exec modification
Summary:
r363675 changed the exec modification helper function, now called
execMayBeModifiedBeforeUse, so that if no UseMI is specified it checks
all instructions in the basic block, even beyond the last use. That
meant that the DPP combiner no longer worked in any basic block that
ended with a control flow instruction, and in particular it didn't work
on code sequences generated by the atomic optimizer.

Fix it by reinstating the old behaviour but in a new helper function
execMayBeModifiedBeforeAnyUse, and limiting the number of instructions
scanned.

Reviewers: arsenm, vpykhtin

Subscribers: kzhuravl, nemanjai, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kbarton, MaskRay, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64393

llvm-svn: 365910
2019-07-12 15:59:40 +00:00
Fangrui Song b251cc0d91 Delete dead stores
llvm-svn: 365903
2019-07-12 14:58:15 +00:00
Stanislav Mekhanoshin 937ff6e701 [AMDGPU] gfx908 agpr spilling
Differential Revision: https://reviews.llvm.org/D64594

llvm-svn: 365833
2019-07-11 21:54:13 +00:00
Stanislav Mekhanoshin e67cc380a8 [AMDGPU] gfx908 mfma support
Differential Revision: https://reviews.llvm.org/D64584

llvm-svn: 365824
2019-07-11 21:19:33 +00:00
Matt Arsenault 71dfb7ec5c AMDGPU: Make s34 the FP register
Make the FP register callee saved.

This is tricky because now the FP needs to be spilled in the prolog
relative to the incoming SP register, rather than the frame register
used throughout the rest of the function. I don't like how this
bypassess the standard mechanism for CSR spills just to get the
correct insert point. I may look for a better solution, since all CSR
VGPRs may also need to have all lanes activated. Another option might
be to make getFrameIndexReference change the base register if the
frame index is a CSR, and then try to figure out the right insertion
point in emitProlog.

If there is a free VGPR lane available for SGPR spilling, try to use
it for the FP. If that would require intrtoducing a new VGPR spill,
try to use a free call clobbered SGPR. Only fallback to introducing a
new VGPR spill as a last resort.

This also doesn't attempt to handle SGPR spilling with scalar stores.

llvm-svn: 365372
2019-07-08 19:03:38 +00:00
Nicolai Haehnle 7cfd99ab15 AMDGPU/GFX10: fix scratch resource descriptor
Summary:
The stride should depend on the wave size, not the hardware generation.

Also, the 32_FLOAT format is 0x16, not 16; though that shouldn't be
relevant.

Change-Id: I088f93bf6708974d085d1c50967f119061da6dc6

Reviewers: arsenm, rampitec, mareko

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63808

llvm-svn: 364788
2019-07-01 15:43:00 +00:00
Nicolai Haehnle 2710171a15 AMDGPU: Write LDS objects out as global symbols in code generation
Summary:
The symbols use the processor-specific SHN_AMDGPU_LDS section index
introduced with a previous change. The linker is then expected to resolve
relocations, which are also emitted.

Initially disabled for HSA and PAL environments until they have caught up
in terms of linker and runtime loader.

Some notes:

- The llvm.amdgcn.groupstaticsize intrinsics can no longer be lowered
  to a constant at compile times, which means some tests can no longer
  be applied.

  The current "solution" is a terrible hack, but the intrinsic isn't
  used by Mesa, so we can keep it for now.

- We no longer know the full LDS size per kernel at compile time, which
  means that we can no longer generate a relevant error message at
  compile time. It would be possible to add a check for the size of
  individual variables, but ultimately the linker will have to perform
  the final check.

Change-Id: If66dbf33fccfbf3609aefefa2558ac0850d42275

Reviewers: arsenm, rampitec, t-tye, b-sumner, jsjodin

Subscribers: qcolombet, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61494

llvm-svn: 364297
2019-06-25 11:52:30 +00:00
Matt Arsenault c67c484f36 AMDGPU: Don't clobber VCC in MUBUF addr64 emulation
Introducing VCC defs during SIFixSGPRCopies is generally
problematic. Avoid it by starting with the VOP3 form with the general
condition register. This is the easiest to fix instance, but doesn't
solve any specific problems I'm looking at.

llvm-svn: 363904
2019-06-20 00:51:28 +00:00
Matt Arsenault e4c2e9b016 AMDGPU: Consolidate some getGeneration checks
This is incomplete, and ideally these would all be removed, but it's
better to localize them to the subtarget first with comments about
what they're for.

llvm-svn: 363902
2019-06-19 23:54:58 +00:00
Matt Arsenault 4d000d2488 AMDGPU: Fix folding immediate into readfirstlane through reg_sequence
The def instruction for the vreg may not match, because it may be
folding through a reg_sequence. The assert was overly conservative and
not necessary. It's not actually important if DefMI really defined the
register, because the fold that will be done cares about the def of
the value that will be folded.

For some reason copies aren't making it through the reg_sequence,
although they should.

llvm-svn: 363876
2019-06-19 20:44:15 +00:00
Matt Arsenault 4d55d024be Reapply "AMDGPU: Add ds_gws_init / ds_gws_barrier intrinsics"
This reapplies r363678, using the correct chain for the CopyToReg for
v0. glueCopyToM0 counterintuitively changes the operands of the
original node.

llvm-svn: 363870
2019-06-19 19:55:27 +00:00
Simon Pilgrim 128ce93c60 Revert rL363678 : AMDGPU: Add ds_gws_init / ds_gws_barrier intrinsics
There may or may not be additional work to handle this correctly on
SI/CI.
........
Breaks EXPENSIVE_CHECKS buildbots - http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/78/

llvm-svn: 363797
2019-06-19 13:00:54 +00:00
Matt Arsenault 8d35dcd703 AMDGPU: Add ds_gws_init / ds_gws_barrier intrinsics
There may or may not be additional work to handle this correctly on
SI/CI.

llvm-svn: 363678
2019-06-18 13:19:57 +00:00
Matt Arsenault f39f3bd056 AMDGPU: Change API for checking for exec modification
Invert the name and return value to better reflect the imprecise
nature.

Force passing in the DefMI, since it's known in the 2 users and could
possibly fail for an arbitrary vreg.

Allow specifying a specific user instruction. Scan through use
instructions, instead of use operands. Add scan thresholds instead of
searching infinitely.

Stop using a set to track seen uses. I didn't understand this usage,
or why it would not check the last use. I don't think the use list has
any particular order.

llvm-svn: 363675
2019-06-18 12:48:36 +00:00
Sander de Smalen 5d6ee76c16 Describe stack-id as an enum
This patch changes MIR stack-id from an integer to an enum,
and adds printing/parsing support for this in MIR files. The default
stack-id '0' is now renamed to 'default'.

This should make MIR tests that have stack objects with different stack-ids
more descriptive. It also clarifies code operating on StackID.

Reviewers: arsenm, thegameg, qcolombet

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D60137

llvm-svn: 363533
2019-06-17 09:13:29 +00:00
Nicolai Haehnle 41abf2766e AMDGPU: Prepare for explicit absolute relocations in code generation
Summary:
We will use absolute relocations for LDS symbols.

Change-Id: I9a32795ed0ea835e433a787129cfe3c57ee9a325

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61492

llvm-svn: 363517
2019-06-16 17:43:37 +00:00
Nicolai Haehnle 6d71be4e67 AMDGPU: Be explicit about whether the high-word in SI_PC_ADD_REL_OFFSET is 0
Summary:
Instead of encoding a high-word of 0 using a fake TargetGlobalAddress,
just use a literal target constant. This simplifies some subsequent changes.

The generated assembly is now more explicit about the kind of relocation
that is to be used.

Change-Id: I066835202d23b5941fa7a358eb4b89e9b71ab6f8

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61491

llvm-svn: 363516
2019-06-16 17:32:01 +00:00
Stanislav Mekhanoshin 5250021672 [AMDGPU] gfx10 conditional registers handling
This is cpp source part of wave32 support, excluding overriden
getRegClass().

Differential Revision: https://reviews.llvm.org/D63351

llvm-svn: 363513
2019-06-16 17:13:09 +00:00
Matt Arsenault 642f39c93e AMDGPU: Fix missing const
llvm-svn: 363383
2019-06-14 13:26:23 +00:00
Stanislav Mekhanoshin 245b5ba344 [AMDGPU] gfx1010 dpp16 and dpp8
Differential Revision: https://reviews.llvm.org/D63203

llvm-svn: 363186
2019-06-12 18:02:41 +00:00
Stanislav Mekhanoshin 5f581c9f08 [AMDGPU] gfx1010 premlane instructions
Differential Revision: https://reviews.llvm.org/D63202

llvm-svn: 363185
2019-06-12 17:52:51 +00:00
Matt Arsenault ddd2c9ac86 AMDGPU: Force skips around traps
llvm-svn: 362852
2019-06-07 23:02:52 +00:00
Matt Arsenault b6cfa129cc AMDGPU: Insert skip branches over return blocks
SIInsertSkips really doesn't understand the control flow, and makes
very stupid assumptions about the block layout. This was able to get
away with not skipping return blocks, since usually after
structurization there is only one placed at the end of the
function. Tail duplication can break this assumption.

llvm-svn: 362754
2019-06-06 22:51:51 +00:00
Alexander Timofeev 37bd9bd137 [AMDGPU] Partial revert for the ba447bae74
"Divergence driven ISel. Assign register class for cross block values
       according to the divergence."
       that discovered the design flaw leading to several issues that
       required to be solved before.

       This change reverts AMDGPU specific changes and keeps common part
       unaffected.

llvm-svn: 362749
2019-06-06 21:13:02 +00:00
Matt Arsenault b812b7a45e AMDGPU: Invert frame index offset interpretation
Since the beginning, the offset of a frame index has been consistently
interpreted backwards. It was treating it as an offset from the
scratch wave offset register as a frame register. The correct
interpretation is the offset from the SP on entry to the function,
before the prolog. Frame index elimination then should select either
SP or another register as an FP.

Treat the scratch wave offset on kernel entry as the pre-incremented
SP. Rely more heavily on the standard hasFP and frame pointer
elimination logic, and clean up the private reservation code. This
saves a copy in most callee functions.

The kernel prolog emission code is still kind of a mess relying on
checking the uses of physical registers, which I would prefer to
eliminate.

Currently selection directly emits MUBUF instructions, which require
using a reference to some register. Use the register chosen for SP,
and then ignore this later. This should probably be cleaned up to use
pseudos that don't refer to any specific base register until frame
index elimination.

Add a workaround for shaders using large numbers of SGPRs. I'm not
sure these cases were ever working correctly, since as far as I can
tell the logic for figuring out which SGPR is the scratch wave offset
doesn't match up with the shader input initialization in the shader
programming guide.

llvm-svn: 362661
2019-06-05 22:20:47 +00:00
Matt Arsenault 0f8a764e8f AMDGPU: Fix using 2 different enums for same operand flags
These enums are really for the same namespace of flags set on
arbitrary MachineOperands, so merge them to avoid value collisions.

llvm-svn: 362640
2019-06-05 20:32:25 +00:00
Dmitry Preobrazhensky 9111f35f02 [AMDGPU][MC] Added support of SCC, VCCZ and EXECZ operands
See bug 39292: https://bugs.llvm.org/show_bug.cgi?id=39292

Reviewers: rampitec, arsenm

Differential Revision: https://reviews.llvm.org/D62660

llvm-svn: 362400
2019-06-03 13:51:24 +00:00
Alexander Timofeev ba447bae74 [AMDGPU] Divergence driven ISel. Assign register class for cross block values according to the divergence.
Details: To make instruction selection really divergence driven it is necessary to assign
             the correct register classes to the cross block values beforehand. For the divergent targets
             same value type requires different register classes dependent on the value divergence.

    Reviewers: rampitec, nhaehnle

    Differential Revision: https://reviews.llvm.org/D59990

    This commit was reverted because of the build failure.
    The reason was mlformed patch.
    Build failure fixed.

llvm-svn: 361741
2019-05-26 20:33:26 +00:00
Peter Collingbourne 3b93737446 Revert r361644, "[AMDGPU] Divergence driven ISel. Assign register class for cross block values according to the divergence."
Broke sanitizer bots:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux/builds/21694/steps/bootstrap%20clang/logs/stdio
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/32478/steps/check-llvm%20asan/logs/stdio

llvm-svn: 361688
2019-05-25 01:52:38 +00:00
Alexander Timofeev dffedea014 [AMDGPU] Divergence driven ISel. Assign register class for cross block values according to the divergence.
Details: To make instruction selection really divergence driven it is necessary to assign
         the correct register classes to the cross block values beforehand. For the divergent targets
         same value type requires different register classes dependent on the value divergence.

Reviewers: rampitec, nhaehnle

Differential Revision: https://reviews.llvm.org/D59990

llvm-svn: 361644
2019-05-24 15:32:18 +00:00
Matt Arsenault ca64ef2043 MC: Allow getMaxInstLength to depend on the subtarget
Keep it optional in cases this is ever needed in some global
context. Currently it's only used for getting an upper bound inline
asm code size.

For AMDGPU, gfx10 increases the maximum instruction size to
20-bytes. This avoids penalizing older subtargets when estimating code
size, and making some annoying branch relaxation test adjustments.

llvm-svn: 361405
2019-05-22 16:28:41 +00:00
Matt Arsenault 2cba91b8db AMDGPU: Assume calls read exec
llvm-svn: 361333
2019-05-21 23:23:16 +00:00
Matt Arsenault 6dd08e335f AMDGPU: Force skip branches over calls
Unfortunately the way SIInsertSkips works is backwards, and is
required for correctness. r338235 added handling of some special cases
where skipping is mandatory to avoid side effects if no lanes are
active. It conservatively handled asm correctly, but the same logic
needs to apply to calls.

Usually the call sequence code is larger than the skip threshold,
although the way the count is computed is really broken, so I'm not
sure if anything was likely to really hit this.

llvm-svn: 361202
2019-05-20 22:04:42 +00:00
Stanislav Mekhanoshin 05791d90c9 [AMDGPU] Fixed handling of imemdiate i1 literals
This bug was exposed by the rL360395.

Differential Revision: https://reviews.llvm.org/D61812

llvm-svn: 360689
2019-05-14 16:18:00 +00:00
Nicolai Haehnle 79ea85c6af AMDGPU: Verify that SOP2/SOPC instructions have at most one immediate operand
Summary:
No test case because I don't know of a way to trigger this, but I
accidentally caused this to fail while working on a different change.

Change-Id: I8015aa447fe27163cc4e4902205a203bd44bf7e3

Reviewers: arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61490

llvm-svn: 360123
2019-05-07 09:19:09 +00:00
Stanislav Mekhanoshin 491746a584 [AMDGPU] gfx1010 verifier changes
Differential Revision: https://reviews.llvm.org/D61521

llvm-svn: 360095
2019-05-06 22:49:45 +00:00
Stanislav Mekhanoshin 971cb8b633 [AMDGPU] gfx1010: prefer V_MUL_LO_U32 over V_MUL_LO_I32
GFX10 deprecates v_mul_lo_i32 instruction, so choose u32 form for
all targets.

Differential Revision: https://reviews.llvm.org/D61525

llvm-svn: 360094
2019-05-06 22:27:05 +00:00
Stanislav Mekhanoshin 28a1936f6d [AMDGPU] gfx1010: use fmac instructions
Differential Revision: https://reviews.llvm.org/D61527

llvm-svn: 359959
2019-05-04 04:20:37 +00:00
Stanislav Mekhanoshin 5cf8167735 [AMDGPU] gfx1010 allows VOP3 to have a literal
Differential Revision: https://reviews.llvm.org/D61413

llvm-svn: 359756
2019-05-02 04:01:39 +00:00
Stanislav Mekhanoshin f2baae0abb [AMDGPU] gfx1010 constant bus limit
Constant bus limit has increased to 2 with GFX10.

Differential Revision: https://reviews.llvm.org/D61404

llvm-svn: 359754
2019-05-02 03:47:23 +00:00
Stanislav Mekhanoshin 692560dc98 [AMDGPU] gfx1010 MIMG implementation
Differential Revision: https://reviews.llvm.org/D61339

llvm-svn: 359698
2019-05-01 16:32:58 +00:00
Stanislav Mekhanoshin a6322941ff [AMDGPU] gfx1010 VMEM and SMEM implementation
Differential Revision: https://reviews.llvm.org/D61330

llvm-svn: 359621
2019-04-30 22:08:23 +00:00
Mark Searles 76c5b62988 Revert "AMDGPU: Split block for si_end_cf"
This reverts commit 7a6ef3004655dd86d722199c471ae78c28e31bb4.

We discovered some internal test failures, so reverting for now.

Differential Revision: https://reviews.llvm.org/D61213

llvm-svn: 359363
2019-04-27 00:51:18 +00:00
Stanislav Mekhanoshin 61beff020e [AMDGPU] gfx1010 VOP3 and VOP3P implementation
Differential Revision: https://reviews.llvm.org/D61202

llvm-svn: 359328
2019-04-26 17:56:03 +00:00
Stanislav Mekhanoshin 8f3da70eed [AMDGPU] gfx1010 VOP2 changes
Differential Revision: https://reviews.llvm.org/D61156

llvm-svn: 359316
2019-04-26 16:37:51 +00:00
Stanislav Mekhanoshin cee607e414 [AMDGPU] Add gfx1010 target definitions
Differential Revision: https://reviews.llvm.org/D61041

llvm-svn: 359113
2019-04-24 17:03:15 +00:00
Bjorn Pettersson 238c9d6308 [CodeGen] Add "const" to MachineInstr::mayAlias
Summary:
The basic idea here is to make it possible to use
MachineInstr::mayAlias also when the MachineInstr
is const (or the "Other" MachineInstr is const).

The addition of const in MachineInstr::mayAlias
then rippled down to the need for adding const
in several other places, such as
TargetTransformInfo::getMemOperandWithOffset.

Reviewers: hfinkel

Reviewed By: hfinkel

Subscribers: hfinkel, MatzeB, arsenm, jvesely, nhaehnle, hiraditya, javed.absar, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60856

llvm-svn: 358744
2019-04-19 09:08:38 +00:00
Matt Arsenault 396653f8a1 AMDGPU: Split block for si_end_cf
Relying on no spill or other code being inserted before this was
precarious. It relied on code diligently checking isBasicBlockPrologue
which is likely to be forgotten.

Ideally this could be done earlier, but this doesn't work because of
phis. Any other instruction can't be placed before them, so we have to
accept the position being incorrect during SSA.

This avoids regressions in the fast register allocator rewrite from
inverting the direction.

llvm-svn: 357634
2019-04-03 20:53:20 +00:00
Neil Henning 0a30f33ce2 [AMDGPU] Pre-allocate WWM registers to reduce VGPR pressure.
This change incorporates an effort by Connor Abbot to change how we deal
with WWM operations potentially trashing valid values in inactive lanes.

Previously, the SIFixWWMLiveness pass would work out which registers
were being trashed within WWM regions, and ensure that the register
allocator did not have any values it was depending on resident in those
registers if the WWM section would trash them. This worked perfectly
well, but would cause sometimes severe register pressure when the WWM
section resided before divergent control flow (or at least that is where
I mostly observed it).

This fix instead runs through the WWM sections and pre allocates some
registers for WWM. It then reserves these registers so that the register
allocator cannot use them. This results in a significant register
saving on some WWM shaders I'm working with (130 -> 104 VGPRs, with just
this change!).

Differential Revision: https://reviews.llvm.org/D59295

llvm-svn: 357400
2019-04-01 15:19:52 +00:00
Matt Arsenault a353fd572a AMDGPU: Make exec mask optimzations more resistant to block splits
Also improve the check for SALU instructions to also ignore
implicit_def and other fake instructions.

llvm-svn: 357170
2019-03-28 14:01:39 +00:00
Matt Arsenault 28f97f1dbc AMDGPU: Don't hardcode num defs for MUBUF instructions
This shouldn't change anything since the no-ret atomics are selected
later.

llvm-svn: 357084
2019-03-27 16:12:29 +00:00
Matt Arsenault bbc59d8d0d AMDGPU: Fix areLoadsFromSameBasePtr for DS atomics
The offset operand index is different for atomics.

llvm-svn: 357073
2019-03-27 15:41:00 +00:00
Tim Renouf 033f99a2e5 [AMDGPU] Added v5i32 and v5f32 register classes
They are not used by anything yet, but a subsequent commit will start
using them for image ops that return 5 dwords.

Differential Revision: https://reviews.llvm.org/D58903

Change-Id: I63e1904081e39a6d66e4eb96d51df25ad399d271
llvm-svn: 356735
2019-03-22 10:11:21 +00:00
Tim Renouf 361b5b2193 [AMDGPU] Support for v3i32/v3f32
Added support for dwordx3 for most load/store types, but not DS, and not
intrinsics yet.

SI (gfx6) does not have dwordx3 instructions, so they are not enabled
there.

Some of this patch is from Matt Arsenault, also of AMD.

Differential Revision: https://reviews.llvm.org/D58902

Change-Id: I913ef54f1433a7149da8d72f4af54dbb13436bd9
llvm-svn: 356659
2019-03-21 12:01:21 +00:00
Michael Liao efb4f9e568 [AMDGPU] Enable code selection using `s_mul_hi_u32`/`s_mul_hi_i32`.
Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59501

llvm-svn: 356405
2019-03-18 20:40:09 +00:00
Tim Renouf cfdfba996b [AMDGPU] Asm/disasm clamp modifier on vop3 int arithmetic
Allow the clamp modifier on vop3 int arithmetic instructions in assembly
and disassembly.

This involved adding a clamp operand to the affected instructions in MIR
and MC, and thus having to fix up several places in codegen and MIR
tests.

Differential Revision: https://reviews.llvm.org/D59267

Change-Id: Ic7775105f02a985b668fa658a0cd7837846a534e
llvm-svn: 356399
2019-03-18 19:35:44 +00:00
Tim Renouf 2e94f6e584 [AMDGPU] Asm/disasm v_cndmask_b32_e64 with abs/neg source modifiers
This commit allows v_cndmask_b32_e64 with abs, neg source
modifiers on src0, src1 to be assembled and disassembled.

This does appear to be allowed, even though they are floating point
modifiers and the operand type is b32.

To do this, I added src0_modifiers and src1_modifiers to the
MachineInstr, which involved fixing up several places in codegen and mir
tests.

Differential Revision: https://reviews.llvm.org/D59191

Change-Id: I69bf4a8c73ebc65744f6110bb8fc4e937d79fbea
llvm-svn: 356398
2019-03-18 19:25:39 +00:00
Michael Liao 6883d7e192 [AMDGPU] Fix SGPR fixing through SCC chaining
Summary:
- During the fixing of SGPR copying from VGPR, ensure users of SCC is
  properly propagated, i.e.
  * only propagate through live def of SCC,
  * skip the SCC-def inst itself, and
  * stop the propagation on the other SCC-def inst after checking its
    SCC-use first.

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59362

llvm-svn: 356258
2019-03-15 12:42:21 +00:00
David Stuttard 20ea21c6ed [AMDGPU] Add support for immediate operand for S_ENDPGM
Summary:
Add support for immediate operand in S_ENDPGM

Change-Id: I0c56a076a10980f719fb2a8f16407e9c301013f6

Reviewers: alexshap

Subscribers: qcolombet, arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, tpr, t-tye, eraman, arphaman, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59213

llvm-svn: 355902
2019-03-12 09:52:58 +00:00
Matt Arsenault f587fd9ce1 AMDGPU: Don't bother checking the chain in areLoadsFromSameBasePtr
This is only called in contexts that are verifying the chain itself,
and the query itself is only asking about the address.

llvm-svn: 355723
2019-03-08 20:30:51 +00:00
Matt Arsenault 07f904befb AMDGPU: Correct DS implementation of areLoadsFromSameBasePtr
This was checking the wrong operands for the base register and the
offsets. The indexes are shifted by the number of output registers
from the machine instruction definition, and the chain is moved to the
end.

llvm-svn: 355722
2019-03-08 20:30:50 +00:00
Changpeng Fang 4cabf6d3b5 AMDGPU: Use MachineInstr::mayAlias to replace areMemAccessesTriviallyDisjoint in LoadStoreOptimizer pass.
Summary:
  This is to fix a memory dependence bug in LoadStoreOptimizer.

Reviewers:
  arsenm, rampitec

Differential Revision:
  https://reviews.llvm.org/D58295

llvm-svn: 354295
2019-02-18 23:00:26 +00:00
Craig Topper 784929d045 Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html

This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.

This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.

There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.

Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii

Differential Revision: https://reviews.llvm.org/D53765

llvm-svn: 353563
2019-02-08 20:48:56 +00:00
Valery Pykhtin 7fe97f8c7c [AMDGPU] Fix DPP combiner
Differential revision: https://reviews.llvm.org/D55444

dpp move with uses and old reg initializer should be in the same BB.
bound_ctrl:0 is only considered when bank_mask and row_mask are fully enabled (0xF). Otherwise the old register value is checked for identity.
Added add, subrev, and, or instructions to the old folding function.
Kill flag is cleared for the src0 (DPP register) as it may be copied into more than one user.

The pass is still disabled by default.

llvm-svn: 353513
2019-02-08 11:59:48 +00:00
Matt Arsenault cba0c6d0c9 AMDGPU: Don't rematerialize mov with implicit operands
This was pulling the mov used for register indexing on gfx9 out of the
loop.

llvm-svn: 353101
2019-02-04 22:26:21 +00:00
Neil Henning 0799352026 [AMDGPU] Fix a weird WWM intrinsic issue.
I found a really strange WWM issue through a very convoluted shader that
essentially boils down to a bug in SIInstrInfo where canReadVGPR did not
correctly identify that WWM is like a copy and can have a VGPR as its
source.

Differential Revision: https://reviews.llvm.org/D56002

llvm-svn: 352500
2019-01-29 14:28:17 +00:00
Matt Arsenault cdd191d9db AMDGPU: Add DS append/consume intrinsics
Since these pass the pointer in m0 unlike other DS instructions, these
need to worry about whether the address is uniform or not. This
assumes the address is dynamically uniform, and just uses
readfirstlane to get a copy into an SGPR.

I don't know if these have the same 16-bit add for the addressing mode
offset problem on SI or not, but I've just assumed they do.

Also includes some misc. changes to avoid test differences between the
LDS and GDS versions.

llvm-svn: 352422
2019-01-28 20:14:49 +00:00
Stanislav Mekhanoshin f92ed6966e [AMDGPU] Fixed hazard recognizer to walk predecessors
Fixes two problems with GCNHazardRecognizer:
1. It only scans up to 5 instructions emitted earlier.
2. It does not take control flow into account. An earlier instruction
from the previous basic block is not necessarily a predecessor.
At the same time a real predecessor block is not scanned.

The patch provides a way to distinguish between scheduler and
hazard recognizer mode. It is OK to work with emitted instructions
in the scheduler because we do not really know what will be emitted
later and its order. However, when pass works as a hazard recognizer
the schedule is already finalized, and we have full access to the
instructions for the whole function, so we can properly traverse
predecessors and their instructions.

Differential Revision: https://reviews.llvm.org/D56923

llvm-svn: 351759
2019-01-21 19:11:26 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Matt Arsenault 85af701e85 AMDGPU: Remove llvm.SI.load.const
It's taken 3 years, but now all of the old AMDGPU and SI intrinsics
are finally gone

llvm-svn: 351586
2019-01-18 20:27:02 +00:00
Marek Olsak c5cec5e1fa AMDGPU: Add llvm.amdgcn.ds.ordered.add & swap
Reviewers: arsenm, nhaehnle

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D52944

llvm-svn: 351351
2019-01-16 15:43:53 +00:00
David Stuttard f77079f892 [AMDGPU] Add support for TFE/LWE in image intrinsics. 2nd try
TFE and LWE support requires extra result registers that are written in the
event of a failure in order to detect that failure case.
The specific use-case that initiated these changes is sparse texture support.

This means that if image intrinsics are used with either option turned on, the
programmer must ensure that the return type can contain all of the expected
results. This can result in redundant registers since the vector size must be a
power-of-2.

This change takes roughly 6 parts:
1. Modify the instruction defs in tablegen to add new instruction variants that
can accomodate the extra return values.
2. Updates to lowerImage in SIISelLowering.cpp to accomodate setting TFE or LWE
(where the bulk of the work for these instruction types is now done)
3. Extra verification code to catch cases where intrinsics have been used but
insufficient return registers are used.
4. Modification to the adjustWritemask optimisation to account for TFE/LWE being
enabled (requires extra registers to be maintained for error return value).
5. An extra pass to zero initialize the error value return - this is because if
the error does not occur, the register is not written and thus must be zeroed
before use. Also added a new (on by default) option to ensure ALL return values
are zero-initialized that is required for sparse texture support.
6. Disable the inst_combine optimization in the presence of tfe/lwe (later TODO
for this to re-enable and handle correctly).

There's an additional fix now to avoid a dmask=0

For an image intrinsic with tfe where all result channels except tfe
were unused, I was getting an image instruction with dmask=0 and only a
single vgpr result for tfe. That is incorrect because the hardware
assumes there is at least one vgpr result, plus the one for tfe.

Fixed by forcing dmask to 1, which gives the desired two vgpr result
with tfe in the second one.

The TFE or LWE result is returned from the intrinsics using an aggregate
type. Look in the test code provided to see how this works, but in essence IR
code to invoke the intrinsic looks as follows:

%v = call {<4 x float>,i32} @llvm.amdgcn.image.load.1d.v4f32i32.i32(i32 15,
                                      i32 %s, <8 x i32> %rsrc, i32 1, i32 0)
%v.vec = extractvalue {<4 x float>, i32} %v, 0
%v.err = extractvalue {<4 x float>, i32} %v, 1

This re-submit of the change also includes a slight modification in
SIISelLowering.cpp to work-around a compiler bug for the powerpc_le
platform that caused a buildbot failure on a previous submission.

Differential revision: https://reviews.llvm.org/D48826

Change-Id: If222bc03642e76cf98059a6bef5d5bffeda38dda


Work around for ppcle compiler bug

Change-Id: Ie284cf24b2271215be1b9dc95b485fd15000e32b
llvm-svn: 351054
2019-01-14 11:55:24 +00:00
Valery Pykhtin b7a459547d Revert "[AMDGPU] Fix DPP combiner"
This reverts commit e3e2923a39cbec3b3bc3a7d3f0e9a77a4115080e, svn revision rL350721

llvm-svn: 350730
2019-01-09 15:21:53 +00:00
Valery Pykhtin 1e0b5c719b [AMDGPU] Fix DPP combiner
Fixed issue with identity values and other cases, f32/f16 identity values to be added later. fma/mac instructions is disabled for now.
Test is fully reworked, added comments. Other fixes:

1. dpp move with uses and old reg initializer should be in the same BB.
2. bound_ctrl:0 is only considered when bank_mask and row_mask are fully enabled (0xF). Othervise the old register value is checked for identity.
3. Added add, subrev, and, or instructions to the old folding function.
4. Kill flag is cleared for the src0 (DPP register) as it may be copied into more than one user.

Differential revision: https://reviews.llvm.org/D55444

llvm-svn: 350721
2019-01-09 13:43:32 +00:00
Ron Lieberman 16de4fd2eb [AMDGPU] Add sdwa support for ADD|SUB U64 decomposed Pseudos
The introduction of S_{ADD|SUB}_U64_PSEUDO instructions which are decomposed
into VOP3 instruction pairs for S_ADD_U64_PSEUDO:
  V_ADD_I32_e64
  V_ADDC_U32_e64
and for S_SUB_U64_PSEUDO
  V_SUB_I32_e64
  V_SUBB_U32_e64
preclude the use of SDWA to encode a constant.
SDWA: Sub-Dword addressing is supported on VOP1 and VOP2 instructions,
but not on VOP3 instructions.

We desire to fold the bit-and operand into the instruction encoding
for the V_ADD_I32 instruction. This requires that we transform the
VOP3 into a VOP2 form of the instruction (_e32).
  %19:vgpr_32 = V_AND_B32_e32 255,
      killed %16:vgpr_32, implicit $exec
  %47:vgpr_32, %49:sreg_64_xexec = V_ADD_I32_e64
      %26.sub0:vreg_64, %19:vgpr_32, implicit $exec
 %48:vgpr_32, dead %50:sreg_64_xexec = V_ADDC_U32_e64
      %26.sub1:vreg_64, %54:vgpr_32, killed %49:sreg_64_xexec, implicit $exec

which then allows the SDWA encoding and becomes
  %47:vgpr_32 = V_ADD_I32_sdwa
      0, %26.sub0:vreg_64, 0, killed %16:vgpr_32, 0, 6, 0, 6, 0,
      implicit-def $vcc, implicit $exec
  %48:vgpr_32 = V_ADDC_U32_e32
      0, %26.sub1:vreg_64, implicit-def $vcc, implicit $vcc, implicit $exec


Differential Revision: https://reviews.llvm.org/D54882

llvm-svn: 348132
2018-12-03 13:04:54 +00:00
Graham Sellers ba559ac058 [AMDGPU] Split 64-Bit XNOR to 64-Bit NOT/XOR
The identity ~(x ^ y) == (~x ^ y) == (x ^ ~y) allows XNOR (XOR/NOT) to turn into NOT/XOR. Handling this case with its own split means we can make the NOT remain in the scalar unit. Previously, we split 64-bit XNOR into two 32-bit XNOR, then lowered. Now, we get three instructions (s_not, v_xor, v_xor) rather than four in the case where either of the sources is a scalar 64-bit.

Add test cases to xnor.ll to attempt XNOR Vx, Sy and XNOR Sx, Vy. Also adding test that uses the opposite identity such that (~x ^ y) on the scalar unit (or vector for gfx906) can generate XNOR. This already worked, but I didn't see a test for it.

Differential: https://reviews.llvm.org/D55071
llvm-svn: 348075
2018-12-01 12:27:53 +00:00
Nicolai Haehnle a7b00058e0 AMDGPU: Divergence-driven selection of scalar buffer load intrinsics
Summary:
Moving SMRD to VMEM in SIFixSGPRCopies is rather bad for performance if
the load is really uniform. So select the scalar load intrinsics directly
to either VMEM or SMRD buffer loads based on divergence analysis.

If an offset happens to end up in a VGPR -- either because a floating
point calculation was involved, or due to other remaining deficiencies
in SIFixSGPRCopies -- we use v_readfirstlane.

There is some unrelated churn in tests since we now select MUBUF offsets
in a unified way with non-scalar buffer loads.

Change-Id: I170e6816323beb1348677b358c9d380865cd1a19

Reviewers: arsenm, alex-t, rampitec, tpr

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D53283

llvm-svn: 348050
2018-11-30 22:55:38 +00:00
Valery Pykhtin 3d9afa273f [AMDGPU] Combine DPP mov with use instructions (VOP1/2/3)
Introduces DPP pseudo instructions and the pass that combines DPP mov with subsequent uses.

Differential revision: https://reviews.llvm.org/D53762

llvm-svn: 347993
2018-11-30 14:21:56 +00:00
David Stuttard c6603861d8 Revert r347871 "Fix: Add support for TFE/LWE in image intrinsic"
Also revert fix r347876

One of the buildbots was reporting a failure in some relevant tests that I can't
repro or explain at present, so reverting until I can isolate.

llvm-svn: 347911
2018-11-29 20:14:17 +00:00
Graham Sellers 04f7a4d2d2 [AMDGPU] Add and update scalar instructions
This patch adds support for S_ANDN2, S_ORN2 32-bit and 64-bit instructions and adds splits to move them to the vector unit (for which there is no equivalent instruction). It modifies the way that the more complex scalar instructions are lowered to vector instructions by first breaking them down to sequences of simpler scalar instructions which are then lowered through the existing code paths. The pattern for S_XNOR has also been updated to apply inversion to one input rather than the output of the XOR as the result is equivalent and may allow leaving the NOT instruction on the scalar unit.

A new tests for NAND, NOR, ANDN2 and ORN2 have been added, and existing tests now hit the new instructions (and have been modified accordingly).

Differential: https://reviews.llvm.org/D54714
llvm-svn: 347877
2018-11-29 16:05:38 +00:00
David Stuttard de02e4b1cc Add support for TFE/LWE in image intrinsics
TFE and LWE support requires extra result registers that are written in the
event of a failure in order to detect that failure case.
The specific use-case that initiated these changes is sparse texture support.

This means that if image intrinsics are used with either option turned on, the
programmer must ensure that the return type can contain all of the expected
results. This can result in redundant registers since the vector size must be a
power-of-2.

This change takes roughly 6 parts:
1. Modify the instruction defs in tablegen to add new instruction variants that
can accomodate the extra return values.
2. Updates to lowerImage in SIISelLowering.cpp to accomodate setting TFE or LWE
(where the bulk of the work for these instruction types is now done)
3. Extra verification code to catch cases where intrinsics have been used but
insufficient return registers are used.
4. Modification to the adjustWritemask optimisation to account for TFE/LWE being
enabled (requires extra registers to be maintained for error return value).
5. An extra pass to zero initialize the error value return - this is because if
the error does not occur, the register is not written and thus must be zeroed
before use. Also added a new (on by default) option to ensure ALL return values
are zero-initialized that is required for sparse texture support.
6. Disable the inst_combine optimization in the presence of tfe/lwe (later TODO
for this to re-enable and handle correctly).

There's an additional fix now to avoid a dmask=0

For an image intrinsic with tfe where all result channels except tfe
were unused, I was getting an image instruction with dmask=0 and only a
single vgpr result for tfe. That is incorrect because the hardware
assumes there is at least one vgpr result, plus the one for tfe.

Fixed by forcing dmask to 1, which gives the desired two vgpr result
with tfe in the second one.

The TFE or LWE result is returned from the intrinsics using an aggregate
type. Look in the test code provided to see how this works, but in essence IR
code to invoke the intrinsic looks as follows:

%v = call {<4 x float>,i32} @llvm.amdgcn.image.load.1d.v4f32i32.i32(i32 15,
                                      i32 %s, <8 x i32> %rsrc, i32 1, i32 0)
%v.vec = extractvalue {<4 x float>, i32} %v, 0
%v.err = extractvalue {<4 x float>, i32} %v, 1

Differential revision: https://reviews.llvm.org/D48826

Change-Id: If222bc03642e76cf98059a6bef5d5bffeda38dda
llvm-svn: 347871
2018-11-29 15:21:13 +00:00
Francis Visoiu Mistrih d7eebd6d83 [CodeGen][NFC] Make `TII::getMemOpBaseImmOfs` return a base operand
Currently, instructions doing memory accesses through a base operand that is
not a register can not be analyzed using `TII::getMemOpBaseRegImmOfs`.

This means that functions such as `TII::shouldClusterMemOps` will bail
out on instructions using an FI as a base instead of a register.

The goal of this patch is to refactor all this to return a base
operand instead of a base register.

Then in a separate patch, I will add FI support to the mem op clustering
in the MachineScheduler.

Differential Revision: https://reviews.llvm.org/D54846

llvm-svn: 347746
2018-11-28 12:00:20 +00:00
Matt Arsenault 88ce3dcbc8 AMDGPU: Record SGPR spills when restoring too
It's possible in some cases to have a restore present
without a corresponding spill. Due to an apparent bug
in D54366 <https://reviews.llvm.org/D54366>, only the
restore for a register was emitted. It's probably
always a bug for this to happen, but due to how SGPR
spilling is implemented, this makes the issues appear
worse than it is.

llvm-svn: 347595
2018-11-26 21:28:40 +00:00
Matt Arsenault eabb8dd015 AMDGPU: Fix analyzeBranch failing with pseudoterminators
If a block had one of the _term instructions used for gluing
exec modifying instructions to the end of the block,
analyzeBranch would fail, preventing the verifier from catching
a broken successor list.

llvm-svn: 347027
2018-11-16 05:03:02 +00:00