In order to avoid duplicating every dpp pseudo opcode that has src1, we
allow it for all opcodes and add manual checks on subtargets that do not
support it.
Names '64BitDPP' and especially 'DPP64' were found misleading, and
DPP64 can easily be mixed with DPP16 and DPP8 while these are
different concepts. DPP16 and DPP8 refers to lanes where DPP64
refers to the operand size.
In fact the essential part here is that these instructions are
executed on the DP ALU, so rename the feature accordingly.
I have also found a bug in a check for these instructions, which is
fixed here and a common utility function is now used.
Differential Revision: https://reviews.llvm.org/D158465
In a lot of places, we were just calling `getNamedOperandIdx` to check if the result was != or == to -1.
This is fine in itself, but it's verbose and doesn't make the intention clear, IMHO. I added a `hasNamedOperand` and replaced all cases I could find with regexes and manually.
Reviewed By: arsenm, foad
Differential Revision: https://reviews.llvm.org/D137540
Due to the encoding changes in GFX11, we had a hack in place that
disables the use of VGPRs above 128. This patch removes the need for
that hack.
We introduce a new register class VGPR_32_Lo128 which is used for 16-bit
operands of VOP1, VOP2, and VOPC instructions. This register class only has the
low 128 VGPRs, but is otherwise identical to VGPR_32. Therefore, 16-bit VOP1,
VOP2, and VOPC instructions are correctly limited to use the first 128
VGPRs, while the other instructions can freely use all 256.
We introduce new pseduo-instructions used on GFX11 which have the suffix
t16 (True 16) to use the VGPR_32_Lo128 register class.
Reviewed By: foad, rampitec, #amdgpu
Differential Revision: https://reviews.llvm.org/D133723
VOPC DPP should not be formed when the row_mask and bank_mask are not
0xf (full) because the resulting VOP DPP would have different semantics
than the MOV DPP followed by VOP. Existing checks in GCNDPPCombine cover
this case but for different reasons, so assert the property for
future-proofing.
Reviewed By: nhaehnle
Differential Revision: https://reviews.llvm.org/D130101
For most DPP instructions, the old operand stores the value that was in
the current lane before the DPP operation, and is tied to the
destination. For VOPC DPP, this is unnecessary and incorrect.
There appears to have been a latent bug related to D122737 with
SIInstrInfo::isOperandLegal. If you checked if a register operand was legal
when the InstructionDesc expected an immediate, it reported that is valid.
Its fix is necessary for and tested in this patch.
Reviewed By: foad, rampitec
Differential Revision: https://reviews.llvm.org/D130040
Modifies the GCNDPPCombine pass to enable DPP formation for the new DPP
instruction in gfx11, namely VOP3 encoded instructions with DPP and VOPC
with DPP.
Depends on D128656
Reviewed By: #amdgpu, rampitec
Differential Revision: https://reviews.llvm.org/D128682
Given a DPP mov like this:
%2:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
...
%3:vgpr_32 = V_MOV_B32_dpp %2, %1, 1, 1, 1, 0, implicit $exec
this patch just removes a check that %2 (the "old reg") was defined in
the same BB as the DPP mov instruction. GCNDPPCombine requires that the
MIR is in SSA form so I don't understand why the BB matters.
This lets the optimization work in more real world cases when the
definition of %2 gets hoisted out of a loop.
Differential Revision: https://reviews.llvm.org/D124182
Don't shrink VOP3 instructions if there are any uses of a carry-out
operand, because the shrunken form of the instruction would write the
carry-out to vcc instead of to a virtual register.
Differential Revision: https://reviews.llvm.org/D100760
NFC. Extract IsShrinkable into a helper function, and
make Subtarget a member variable.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D99099
Change-Id: If4bc97a88a9ae4eb1df47e717345d46a6ed515bf
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).
Also fix an SSA violation in a test the MIRParser/verifier fails to
catch. It's illegal to define a subregister in SSA. For the purpose of
the test, it just needs to define the super-register to use the
subregister in the use operand.
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.
Added a check to make sure that the selected dpp opcode is supported by target.
Reviewers: vpykhtin, arsenm, rampitec
Differential Revision: https://reviews.llvm.org/D70402
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
If original instruction did not have source modifiers they were
not added to the new DPP instruction as well, even if needed.
Differential Revision: https://reviews.llvm.org/D68729
llvm-svn: 374241
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
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
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
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
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
Introduces DPP pseudo instructions and the pass that combines DPP mov with subsequent uses.
Differential revision: https://reviews.llvm.org/D53762
llvm-svn: 347993
