Making sure we don't truncate / extend pointers, don't try to change
vector topology or bitcast vectors to scalars or back, and most
importantly, don't extend to a smaller type or truncate to a large
one.
Reviewers: qcolombet t.p.northover aditya_nandakumar
Reviewed By: qcolombet
Subscribers: rovka, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D46490
llvm-svn: 331718
Remove the old waitcnt pass ( si-insert-waits ), which is no longer maintained
and getting crufty
Differential Revision: https://reviews.llvm.org/D46448
llvm-svn: 331641
Summary:
Previously, all DS ops forced WQM in a pixel shader. That was a hack to
allow for graphics frontends using ds_swizzle to implement explicit
derivatives, on SI/CI at least where DPP is not available. But it forced
WQM for _any_ DS op.
With this commit, DS ops no longer force WQM. Both graphics frontends
(Mesa and LLPC) need to change to issue an explicit llvm.amdgcn.wqm
intrinsic call when calculating explicit derivatives.
The required Mesa change is: "amd/common: use llvm.amdgcn.wqm for
explicit derivatives".
Subscribers: qcolombet, arsenm, kzhuravl, wdng, nhaehnle, yaxunl, dstuttard, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D46051
Change-Id: I9b745b626fa91bbd66456e6cf41ee07eeea42f81
llvm-svn: 331633
As Roman Tereshin pointed out in https://reviews.llvm.org/D45541, the
-global-isel option is redundant when -run-pass is given. -global-isel sets up
the GlobalISel passes in the pass manager but -run-pass skips that entirely and
configures it's own pipeline.
llvm-svn: 331603
- Predicate D16 patterns on this new feature
- Added this new feature to gfx900/2/4
Differential Revision: https://reviews.llvm.org/D46366
llvm-svn: 331551
Summary: performAddCombine should run after DAG is legalized; Otherwise generic optimization
in the DAGCombiner can optimize an addcarry+trunc into an addcarry instruction with
illegal types.
Author: FarhanaAleen
Reviewed By: rampitec
Subscribers: llvm-commits, AMDGPU
Differential Revision: https://reviews.llvm.org/D46337
llvm-svn: 331368
- Add "amdgpu-waitcnt-forcezero" to force all waitcnt instrs to be emitted as s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
- Add debug counters to control force emit of s_waitcnt instrs; debug counters:
si-insert-waitcnts-forceexp: force emit s_waitcnt expcnt(0) instrs
si-insert-waitcnts-forcevm: force emit s_waitcnt lgkmcnt(0) instrs
si-insert-waitcnts-forcelgkm: force emit s_waitcnt vmcnt(0) instrs
- Add some debug statements
Note that a variant of this patch was previously committed/reverted.
Differential Revision: https://reviews.llvm.org/D45888
llvm-svn: 330862
Debug var, expr and loc were only supported for non-fixed stack objects.
This patch adds the following fields to the "fixedStack:" entries, and
renames the ones from "stack:" to:
* debug-info-variable
* debug-info-expression
* debug-info-location
Differential Revision: https://reviews.llvm.org/D46032
llvm-svn: 330859
Summary: This is no longer used by mesa since its 18.0.0 release.
Reviewers: nhaehnle
Reviewed By: nhaehnle
Subscribers: arsenm, kzhuravl, wdng, yaxunl, dstuttard, tpr, llvm-commits, t-tye
Differential Revision: https://reviews.llvm.org/D45988
llvm-svn: 330775
If a packed inline constant is sign extended it must be truncated
after the shift. I.e. a constant (0xH0000, 0xHBC00), will be represented
as 0xFFFFFFFFBC000000 in the IR because the immediate is sign extended
to 64 bit. After the value shifted right by 16 to use it in a low part
with op_sel_hi it becomes 0xFFFFFFFFBC00 and does not qualify as inline
constant any longer.
Fixed the error and added verification code. Without the fix and with
the verification bug is causing pk_max_f16_literal.ll to fail.
Differential Revision: https://reviews.llvm.org/D45987
llvm-svn: 330752
It's possible to validly spill the frame offset register
in a call sequence to a VGPR. There are definitely issues
with SGPR spilling to memory, so move the assert later.
llvm-svn: 330612
Summary:
See the new test case; this is really unlikely to happen with real code,
but I ran into this while attempting to bugpoint-reduce a different issue.
Change-Id: I9ade1dc1aa8fd9c4d9fc83661d7b80e310b5c4a6
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D45885
llvm-svn: 330585
Summary:
This fixes a case where the argument to a sendmsg intrinsic
ends up in a VGPR, for whatever reason.
The underlying performance issue is that a multiplication that
can be an s_mul_i32 is instead needlessly generated as
v_mul_u32_u24, but this is not addressed by this patch.
Change-Id: I61fd4034314d5acdf6074632c30b65364dfa7328
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D45826
llvm-svn: 330393
We should also check that the "bottom" basic block of a loopis a successor of the "header" basic block, otherwise we don't propagate the information correctly when the CFG is complex. This fixes an important rendering problem with Wolfsentein 2, because of one vector-memory wait was missing.
Differential Revision: https://reviews.llvm.org/D43831
llvm-svn: 330337
Summary:
A change to use divergence analysis in the AMDGPU backend was getting formal
arguments incorrect (not tagged as divergent) unless they were VGPR0, VGPR1 or
VGPR2
For graphics shaders it is possible to have more than these passed in as VGPR
Modified the checking code to check for any VGPR registers passed in as formal
arguments.
Also, some intrinsics that are sources of divergence may have been lowered
during instruction selection and are missed on subsequent calls to
isSDNodeSourceOfDivergence - added the relevant AMDGPUISD checks as well.
Finally, the FunctionLoweringInfo tracks virtual registers that are live across
basic block boundaries. This is used to check for divergence of CopyFromRegister
registers using the DivergenceAnalysis analysis. For multiple blocks the lazily
evaluated inverted map VirtReg2Value was not cleared when the ValueMap map was.
Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D45372
Change-Id: I112f3bd6dfe0f62e63ce9b43b893982778e4bee3
llvm-svn: 330257
Summary:
This fixes the number of SGPRs and VGPRs in the *_RSRC1 register to
allow for registers set up in wave dispatch, even if those registers are
not used in the shader.
Re-landed after noticing that the buildbot failure from 329808 seemed to
be unrelated.
Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, dstuttard, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D45503
Change-Id: I6575f0e0d2a528d1319d0b289f0ebe4510fa5771
llvm-svn: 329826
Two issues were fixed:
runtime has difficulty to allocate memory for an external symbol of a
kernel and set the address of the external symbol, therefore make the runtime
handle of an enqueued kernel an ordinary global variable. Runtime only needs
to store the address of the loaded kernel to the handle and has verified
that this approach works.
handle the situation where __enqueue_kernel* gets inlined therefore
the enqueued kernel may be used through a constant expr instead
of an instruction.
Differential Revision: https://reviews.llvm.org/D45187
llvm-svn: 329815
This reverts 329808. That change caused a report of a failure in
test/CodeGen/MIR/AMDGPU/mir-canon-multi.mir that I didn't see. I suspect
it is an expensive-check-only error.
Change-Id: I8133f26f15e7d5ec2b09c687c12cd70e918461b0
llvm-svn: 329811
Summary:
This fixes the number of SGPRs and VGPRs in the *_RSRC1 register to
allow for registers set up in wave dispatch, even if those registers are
not used in the shader.
Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, dstuttard, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D45503
Change-Id: I6575f0e0d2a528d1319d0b289f0ebe4510fa5771
llvm-svn: 329808
Author: Samuel Pitoiset
ds_read_b128 and ds_write_b128 have been recently enabled
under the amdgpu-ds128 option because the performance benefit
is unclear.
Though, using 128-bit loads/stores for the local address space
appears to introduce regressions in tessellation shaders. Not
sure what is broken, but as ds_read_b128/ds_write_b128 are not
enabled by default, just introduce a global option and enable
128-bit only if requested (until it's fixed/used correctly).
v2: - fix regressions in merge-stores.ll and multiple_tails.ll
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105464
llvm-svn: 329764
Summary:
For OS type AMDPAL, the scratch descriptor is loaded from offset 0 of
the GIT, whose 32 bit pointer is in s0 (s8 for gfx9 merged shaders).
This commit fixes that to use offset 0x10 instead of offset 0 for a
compute shader, per the PAL ABI spec.
V2: Ensure s0 (s8 for gfx9 merged shader) is marked live-in when loading
scratch descriptor from GIT.
Reviewers: kzhuravl, nhaehnle, timcorringham
Subscribers: kzhuravl, wdng, yaxunl, t-tye, llvm-commits, dstuttard, nhaehnle, arsenm
Differential Revision: https://reviews.llvm.org/D44468
Change-Id: I93dffa647758e37f613bb5e0dfca840d82e6d26f
llvm-svn: 329690
Author: Samuel Pitoiset
ds_read_b128 and ds_write_b128 have been recently enabled
under the amdgpu-ds128 option because the performance benefit
is unclear.
Though, using 128-bit loads/stores for the local address space
appears to introduce regressions in tessellation shaders. Not
sure what is broken, but as ds_read_b128/ds_write_b128 are not
enabled by default, just introduce a global option and enable
128-bit only if requested (until it's fixed/used correctly).
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105464
llvm-svn: 329591
Currently it is 6. If the "feature" was not used, report dummy
hidden argument. Otherwise it does not match the kernarg size
reported in the kernel header.
Differential Revision: https://reviews.llvm.org/D45129
llvm-svn: 329341
Summary:
These new image intrinsics contain the texture type as part of
their name and have each component of the address/coordinate as
individual parameters.
This is a preparatory step for implementing the A16 feature, where
coordinates are passed as half-floats or -ints, but the Z compare
value and texel offsets are still full dwords, making it difficult
or impossible to distinguish between A16 on or off in the old-style
intrinsics.
Additionally, these intrinsics pass the 'texfailpolicy' and
'cachectrl' as i32 bit fields to reduce operand clutter and allow
for future extensibility.
v2:
- gather4 supports 2darray images
- fix a bug with 1D images on SI
Change-Id: I099f309e0a394082a5901ea196c3967afb867f04
Reviewers: arsenm, rampitec, b-sumner
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, llvm-commits, t-tye
Differential Revision: https://reviews.llvm.org/D44939
llvm-svn: 329166
Summary:
When an i1-value is defined inside of a loop and used outside of it, we
cannot simply use the SGPR bitmask from the loop's last iteration.
There are also useful and correct cases of an i1-value being copied between
basic blocks, e.g. when a condition is computed outside of a loop and used
inside it. The concept of dominators is not sufficient to capture what is
going on, so I propose the notion of "lane-dominators".
Fixes a bug encountered in Nier: Automata.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103743
Change-Id: If37b969ddc71d823ab3004aeafb9ea050e45bd9a
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, wdng, mgorny, yaxunl, dstuttard, tpr, llvm-commits, t-tye
Differential Revision: https://reviews.llvm.org/D40547
llvm-svn: 329164
Summary: There are no packed instructions for min3 or max3. So, performMinMaxCombine should not optimize vectors of f16 to min3/max3.
Author: FarhanaAleen
Reviewed By: arsenm
Subscribers: llvm-commits, AMDGPU
Differential Revision: https://reviews.llvm.org/D45219
llvm-svn: 329131
Summary:
The phase attempts to transform operations that extract a portion of a value
into an SDWA src operand in cases where that value is used only once. It
was not prepared for this use to be the preserved portion of a value for
dst:UNUSED_PRESERVE, resulting in a crash or assert.
This change either rejects the illegal SDWA attempt, or in the case where
dst:WORD_1 and the src_sel would be WORD_0, removes the unneeded
extract instruction.
Reviewers: arsenm, #amdgpu
Reviewed By: arsenm, #amdgpu
Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D44364
llvm-svn: 328856
While the stack access instructions don't care about
alignment > 4, some transformations on the pointer calculation
do make assumptions based on knowing the low bits of a pointer
are 0. If a stack object ends up being accessed through its
absolute address (relative to the kernel scratch wave offset),
the addressing expression may depend on the stack frame being
properly aligned. This was breaking in a testcase due to the
add->or combine.
I think some of the SP/FP handling logic is still backwards,
and overly simplistic to support all of the stack features.
Code which tries to modify the SP with inline asm for example
or variable sized objects will probably require redoing this.
llvm-svn: 328831
This reverts commit 0daf86291d3aa04d3cc280cd0ef24abdb0174981.
It was causing an assert in test/CodeGen/AMDGPU/amdpal.ll only on a
release-with-asserts build. I will resubmit the change when I have fixed
that.
Change-Id: If270594eba27a7dc4076bdeab3fa8e6bfda3288a
llvm-svn: 328695
Summary:
For OS type AMDPAL, the scratch descriptor is loaded from offset 0 of
the GIT, whose 32 bit pointer is in s0 (s8 for gfx9 merged shaders).
This commit fixes that to use offset 0x10 instead of offset 0 for a
compute shader, per the PAL ABI spec.
Reviewers: kzhuravl, nhaehnle, timcorringham
Subscribers: kzhuravl, wdng, yaxunl, t-tye, llvm-commits, dstuttard, nhaehnle, arsenm
Differential Revision: https://reviews.llvm.org/D44468
Change-Id: I93dffa647758e37f613bb5e0dfca840d82e6d26f
llvm-svn: 328673
Summary:
Rev 327580 "[CodeGen] Use MIR syntax for MachineMemOperand printing"
broke -print-machineinstrs for us on AMDGPU, because we have custom
pseudo source values, and MIR serialization does not implement that.
This commit at least restores the functionality of -print-machineinstrs,
even if it does not properly implement the missing MIR serialization
functionality.
Differential Revision: https://reviews.llvm.org/D44871
Change-Id: I44961c0b90bf6d48c01484ed7a4e466fd300db66
llvm-svn: 328668
Before this was not done if the function had no calls in it. This
is still a possible issue with any callable function, regardless
of calls present.
llvm-svn: 328659
The combine on a select of a load only triggers for
addrspace 0, and discards the MachinePointerInfo. The
conservative default needs to be used for this.
llvm-svn: 328652
In a function, s5 is used as the frame base SGPR. If a function
is calling another function, during the call sequence
it is copied to a preserved SGPR and restored.
Before it was possible for the scheduler to move stack operations
before the restore of s5, since there's nothing to associate
a frame index access with the restore.
Add an implicit use of s5 to the adjcallstack pseudo which ends
the call sequence to preven this from happening. I'm not 100%
satisfied with this solution, but I'm not sure what else would be
better.
llvm-svn: 328650
Add two additional implicit arguments for OpenCL for the AMDGPU target using the AMDHSA runtime to support device enqueue.
Differential Revision: https://reviews.llvm.org/D44697
llvm-svn: 328351
- Remove use of the opencl and amdopencl environment member of the target triple for the AMDGPU target.
- Use function attribute to communicate to the AMDGPU backend to add implicit arguments for OpenCL kernels for the AMDHSA OS.
Differential Revision: https://reviews.llvm.org/D43736
llvm-svn: 328349
Normally DCE kills these, but at -O0 these get left behind
leaving suspicious looking illegal copies.
Replace with IMPLICIT_DEF to avoid iterator issues.
llvm-svn: 327842
Get rid of the "; mem:" suffix and use the one we use in MIR: ":: (load 2)".
rdar://38163529
Differential Revision: https://reviews.llvm.org/D42377
llvm-svn: 327580
Since the enqueued kernels have internal linkage, their names may be dropped.
In this case, give them unique names __amdgpu_enqueued_kernel or
__amdgpu_enqueued_kernel.n where n is a sequential number starting from 1.
Differential Revision: https://reviews.llvm.org/D44322
llvm-svn: 327291
Summary: Starting from GCN 2nd generation, ISA supports ds_read_b128 on top of ds_read_b64.
This patch supports ds_read_b128 instruction pattern and generation of this instruction.
In the vectorizer, this patch also widen the vector length so that vectorizer generates
128 bit loads for local address-space which gets translated to ds_read_b128.
Since the performance benefit is not clear; compiler generates ds_read_b128 under -amdgpu-ds128.
Author: FarhanaAleen
Reviewed By: rampitec, arsenm
Subscribers: llvm-commits, AMDGPU
Differential Revision: https://reviews.llvm.org/D44210
llvm-svn: 327153
Summary: GCN ISA supports instructions that can read 16 consecutive dwords from memory through the scalar data cache;
loadstoreVectorizer should take advantage of the wider vector length and pack 16/8 elements of dwords/quadwords.
Author: FarhanaAleen
Reviewed By: rampitec
Subscribers: llvm-commits, AMDGPU
Differential Revision: https://reviews.llvm.org/D44179
llvm-svn: 326910
One addrspacecast disappeared in clang emitted IR for
block invoke function due to adoption of the new
addr space mapping.
Differential Revision: https://reviews.llvm.org/D43785
llvm-svn: 326806
i16 capable ASICs do not support i16 operands for this instruction.
Add tablegen pattern to merge chained i16 additions.
Differential Revision: https://reviews.llvm.org/D43985
llvm-svn: 326535
Summary:
For use by LLPC SPV_AMD_shader_ballot extension.
The v_writelane instruction was already implemented for use by SGPR
spilling, but I had to add an extra dummy operand tied to the
destination, to represent that all lanes except the selected one keep
the old value of the destination register.
.ll test changes were due to schedule changes caused by that new
operand.
Differential Revision: https://reviews.llvm.org/D42838
llvm-svn: 326353
Re-enable commit r323991 now that r325931 has been committed to make
MachineOperand::isRenamable() check more conservative w.r.t. code
changes and opt-in on a per-target basis.
llvm-svn: 326208
Summary:
With OS type AMDPAL, the scratch descriptor is hardwired to be loaded
from offset 0 of the global information table, whose low pointer is
passed in s0. For a merge shader on gfx9+, it needs to be s8 instead, as
the hardware reserves s0-s7.
Reviewers: kzhuravl
Subscribers: arsenm, nhaehnle, dstuttard, llvm-commits, t-tye, yaxunl, wdng, kzhuravl
Differential Revision: https://reviews.llvm.org/D42203
llvm-svn: 326088
V_SUBBREV_U32 is a commute opcode for V_SUBB_U32. However, when
we try to commute V_SUBB_U32 in order to shrink it we do not then
process V_SUBBREV_U32 and it stay VOP3. This is fixed.
Differential Revision: https://reviews.llvm.org/D43699
llvm-svn: 326011
Summary:
Add a target option AllowRegisterRenaming that is used to opt in to
post-register-allocation renaming of registers. This is set to 0 by
default, which causes the hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq
fields of all opcodes to be set to 1, causing
MachineOperand::isRenamable to always return false.
Set the AllowRegisterRenaming flag to 1 for all in-tree targets that
have lit tests that were effected by enabling COPY forwarding in
MachineCopyPropagation (AArch64, AMDGPU, ARM, Hexagon, Mips, PowerPC,
RISCV, Sparc, SystemZ and X86).
Add some more comments describing the semantics of the
MachineOperand::isRenamable function and how it is set and maintained.
Change isRenamable to check the operand's opcode
hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq bit directly instead of
relying on it being consistently reflected in the IsRenamable bit
setting.
Clear the IsRenamable bit when changing an operand's register value.
Remove target code that was clearing the IsRenamable bit when changing
registers/opcodes now that this is done conservatively by default.
Change setting of hasExtraSrcRegAllocReq in AMDGPU target to be done in
one place covering all opcodes that have constant pipe read limit
restrictions.
Reviewers: qcolombet, MatzeB
Subscribers: aemerson, arsenm, jyknight, mcrosier, sdardis, nhaehnle, javed.absar, tpr, arichardson, kristof.beyls, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, escha, nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D43042
llvm-svn: 325931
Summary:
There are transformation that change setcc into other constructs, and transform that try to reconstruct a setcc from the brcond condition. Depending on what order these transform are done, the end result differs.
Most of the time, it is preferable to get a setcc as a brcond argument (and this is why brcond try to recreate the setcc in the first place) so we ensure this is done every time by also doing it at the setcc level when the only user is a brcond.
Reviewers: spatel, hfinkel, niravd, craig.topper
Subscribers: nhaehnle, llvm-commits
Differential Revision: https://reviews.llvm.org/D41235
llvm-svn: 325892
Summary:
This handles def-after-use of physregs, and allows us to merge loads and
stores even across some physreg defs (typically M0 defs).
Change-Id: I076484b2bda27c2cf46013c845a0380c5b89b67b
Reviewers: arsenm, mareko, rampitec
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D42647
llvm-svn: 325882
Summary:
This fixes cases like the new test @nonuniform. In that test, %cc itself
is a uniform value; however, when reading it after the end of the loop in
basic block %if, its value is effectively non-uniform.
This problem was encountered in
https://bugs.freedesktop.org/show_bug.cgi?id=103743; however, this change
in itself is not sufficient to fix that bug, as there is another issue
in the AMDGPU backend.
Change-Id: I32bbffece4a32f686fab54964dae1a5dd72949d4
Reviewers: arsenm, rampitec, jlebar
Subscribers: wdng, tpr, llvm-commits
Differential Revision: https://reviews.llvm.org/D40546
llvm-svn: 325881
Summary:
The machine instruction scheduler was illegally moving a buffer store
past a buffer load with the same descriptor and offset. Fixed by marking
buffer ops as mayAlias and isAliased. This may be overly conservative,
and we may need to revisit.
Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, dstuttard, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D43332
Change-Id: Iff3173d9e0653e830474546276ab9d30318b8ef7
llvm-svn: 325567
Summary: GCN ISA supports instructions that can read 16 consecutive dwords from memory through the scalar data cache; loadstoreVectorizer should take advantage of the wider vector length and pack 16/8 elements of dwords/quadwords.
Author: FarhanaAleen
Reviewed By: rampitec
Subscribers: llvm-commits, AMDGPU
Differential Revision: https://reviews.llvm.org/D43275
llvm-svn: 325518
Enable multiple COPY hints to eliminate more COPYs during register allocation.
Note that this is something all targets should do, see
https://reviews.llvm.org/D38128.
Review: Stanislav Mekhanoshin, Tom Stellard.
llvm-svn: 325425
This reverts commit r323991.
This commit breaks target that don't model all the register constraints
in TableGen. So far the workaround was to set the
hasExtraXXXRegAllocReq, but it proves that it doesn't cover all the
cases.
For instance, when mutating an instruction (like in the lowering of
COPYs) the isRenamable flag is not properly updated. The same problem
will happen when attaching machine operand from one instruction to
another.
Geoff Berry is working on a fix in https://reviews.llvm.org/D43042.
llvm-svn: 325421
Summary:
This patch extends the promotion of alloca to vector to the arrays of up to 16 elements. Also we introduce
an option, -disable-promote-alloca-to-vector, to switch promotion to vector off, if needed.
Reviewers:
arsenm
Differential Revision:
https://reviews.llvm.org/D33559
llvm-svn: 325372
Summary:
In the current implementation of GPR Indexing Mode when the index is of non-uniform, the s_set_gpr_idx_off instruction
is incorrectly inserted after the loop. This will lead the instructions with vgpr operands (v_readfirstlane for example) to read incorrect
vgpr.
In this patch, we fix the issue by inserting s_set_gpr_idx_on/off immediately around the interested instruction.
Reviewers:
rampitec
Differential Revision:
https://reviews.llvm.org/D43297
llvm-svn: 325355
Kernel arguments likely read by all workitems and should not bypass
cache. Fixes performance hit in sub-dword argument loads.
Differential Revision: https://reviews.llvm.org/D43249
llvm-svn: 325146
When adding operands to machine instructions in case of
RegisterSDNodes, generate a COPY node in case the register class
does not match the one in the instruction definition.
Differental Revision: https://reviews.llvm.org/D35561
llvm-svn: 324733
Note: This is a candidate for LLVM 6.0, because it was planned to be
in that release but was delayed due to a long review period.
Merge conflict in release_60 - resolution:
Add "-p6:32:32" into the second (non-amdgiz) string.
Only scalar loads support 32-bit pointers. An address in a VGPR will
fail to compile. That's OK because the results of loads will only be used
in places where VGPRs are forbidden.
Updated AMDGPUAliasAnalysis and used SReg_64_XEXEC.
The tests cover all uses cases we need for Mesa.
Reviewers: arsenm, nhaehnle
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D41651
llvm-svn: 324487
Summary:
I checked the AMD closed source compiler and the workaround is only
needed when x3 is emulated as x4, which we don't do in LLVM.
SMEM x3 opcodes don't exist, and instead there is a possibility to use x4
with the last component being unused. If the last component is out of
buffer bounds and falls on the next 4K page, the hw hangs.
Reviewers: arsenm, nhaehnle
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, llvm-commits, t-tye
Differential Revision: https://reviews.llvm.org/D42756
llvm-svn: 324486
1. Run the memory legalizer prior to the waitcnt pass; keep the policy that the waitcnt pass does not remove any waitcnts within the incoming IR.
2. The waitcnt pass doesn't (yet) track waitcnts that exist prior to the waitcnt pass (it just skips over them); because the waitcnt pass is ignorant of them, it may insert a redundant waitcnt. To avoid this, check the prev instr. If it and the to-be-inserted waitcnt are the same, suppress the insertion. We keep the existing waitcnt under the assumption that whomever, e.g., the memory legalizer, inserted it knows what they were doing.
3. Follow-on work: teach the waitcnt pass to record the pre-existing waitcnts for better waitcnt production.
Differential Revision: https://reviews.llvm.org/D42854
llvm-svn: 324440
X86 currently has a late DAG combine after cttz/ctlz are turned into BSR+BSF+CMOV to detect this and remove the CMOV. But we should be able to do this much earlier and avoid creating the cmov all together.
For the changed AMDGPU test case it appears that previously the i8 cttz was type legalized to i16 which introduced an OR with 256 in order to limit the result to 8 on the widened type. At this point the result is known to never be zero, but nothing checked that. Then operation legalization is told to promote all i16 cttz to i32. This introduces an extend and a truncate and another OR with 65536 to limit the result to 16. With the DAG combiner change we are able to prevent the creation of the second OR since the opcode will have been changed to cttz_zero_undef after the first OR. I the lack of the OR caused the instruction to change to v_ffbl_b32_sdwa
Differential Revision: https://reviews.llvm.org/D42985
llvm-svn: 324427
Summary:
Now we generate PAL metadata for the amdpal os type, there is no need to
generate the .AMDGPU.config section.
Reviewers: arsenm, nhaehnle, dstuttard
Subscribers: kzhuravl, wdng, yaxunl, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D37760
Change-Id: I303c5fad66656ce97293da60621afac6595b4c18
llvm-svn: 324346
Summary:
This change extends MachineCopyPropagation to do COPY source forwarding
and adds an additional run of the pass to the default pass pipeline just
after register allocation.
This version of this patch uses the newly added
MachineOperand::isRenamable bit to avoid forwarding registers is such a
way as to violate constraints that aren't captured in the
Machine IR (e.g. ABI or ISA constraints).
This change is a continuation of the work started in D30751.
Reviewers: qcolombet, javed.absar, MatzeB, jonpa, tstellar
Subscribers: tpr, mgorny, mcrosier, nhaehnle, nemanjai, jyknight, hfinkel, arsenm, inouehrs, eraman, sdardis, guyblank, fedor.sergeev, aheejin, dschuff, jfb, myatsina, llvm-commits
Differential Revision: https://reviews.llvm.org/D41835
llvm-svn: 323991
Discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120320.html
In preparation for adding support for named vregs we are changing the sigil for
physical registers in MIR to '$' from '%'. This will prevent name clashes of
named physical register with named vregs.
llvm-svn: 323922
Sometimes users do not specify data layout in LLVM assembly and let llc set the
data layout by target triple after loading the LLVM assembly.
Currently the parser checks alloca address space no matter whether the LLVM
assembly contains data layout definition, which causes false alarm since the
default data layout does not contain the correct alloca address space.
The parser also calls verifier to check debug info and updating invalid debug
info. Currently there is no way to let the verifier to check debug info only.
If the verifier finds non-debug-info issues the parser will fail.
For llc, the fix is to remove the check of alloca addr space in the parser and
disable updating debug info, and defer the updating of debug info and
verification to be after setting data layout of the IR by target.
For other llvm tools, since they do not override data layout by target but
instead can override data layout by a command line option, an argument for
overriding data layout is added to the parser. In cases where data layout
overriding is necessary for the parser, the data layout can be provided by
command line.
Differential Revision: https://reviews.llvm.org/D41832
llvm-svn: 323826
Mark more opcodes as hasExtraSrcRegAllocReq so that their operands will
be marked as not renamable, to avoid copy forwarding violating the
constraint that only one operand may use the constant bus.
These changes fix a few mis-compiles when copy forwarding is enabled in
MachineCopyPropagation by D41835 (and were reviewed as part of that change).
llvm-svn: 323794
-amdgpu-waitcnt-forcezero={1|0} Force all waitcnt instrs to be emitted as s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
-amdgpu-waitcnt-forceexp=<n> Force emit a s_waitcnt expcnt(0) before the first <n> instrs
-amdgpu-waitcnt-forcelgkm=<n> Force emit a s_waitcnt lgkmcnt(0) before the first <n> instrs
-amdgpu-waitcnt-forcevm=<n> Force emit a s_waitcnt vmcnt(0) before the first <n> instrs
This patch was pushed ( abb190fd51cd2f9a9eef08c024e109f7f7e909fc ), which caused a buildbot failure, reverted ( 6227480d74da507cf8e1b4bcaffbdb9fb875b4b8 ), and then updated to fix buildbot failures (this patch).
Differential Revision: https://reviews.llvm.org/D40091
llvm-svn: 323788
Patch by: Bas Nieuwenhuizen
Just use the _e64 variant if needed. This should be possible as per
def : Pat <
(int_amdgcn_kill (i1 (setcc f32:$src, InlineFPImm<f32>:$imm, cond:$cond))),
(SI_KILL_F32_COND_IMM_PSEUDO $src, (bitcast_fpimm_to_i32 $imm), (cond_as_i32imm $cond))
> ;
I don't think we can get an immediate for the other operand for which we
need the second 32-bit word.
https://reviews.llvm.org/D42302
llvm-svn: 323706
Add support for printing / parsing the addrspace of a MachineMemOperand.
Fixes PR35970.
Differential Revision: https://reviews.llvm.org/D42502
llvm-svn: 323521
- using qualified pointer addrspace in intrinsics class to avoid .f32 mangling
- changed too common atomic mangling to ds
- added missing intrinsics to AMDGPUTTIImpl::getTgtMemIntrinsic
Reviewed by: b-sumner
Differential Revision: https://reviews.llvm.org/D42383
llvm-svn: 323516
It causes regressions in various OpenGL test suites.
Keep the test cases introduced by r321751 as XFAIL, and add a test case
for the regression.
Change-Id: I90b4cc354f68cebe5fcef1f2422dc8fe1c6d3514
Bugzilla: https://bugs.llvm.org/show_bug.cgi?id=36015
llvm-svn: 323355
For the included test case, the DAG transformation
concat_vectors(scalar, undef) -> scalar_to_vector(sclr)
would attempt to create a v2i32 vector for a v9i8
concat_vector. Bail out to avoid creating a bitcast with
mismatching sizes later on.
Differential Revision: https://reviews.llvm.org/D42379
llvm-svn: 323312
Fix a bug in ScheduleDAGMILive::scheduleMI which causes BotRPTracker not tracking CurrentBottom in some rare cases involving llvm.dbg.value.
This issues causes amdgcn target to assert when compiling some user codes with -g.
Differential Revision: https://reviews.llvm.org/D42394
llvm-svn: 323214
- Change inserted add ( V_ADD_{I|U}32_e32 ) to _e64 version ( V_ADD_{I|U}32_e64 ) so that the add uses a vreg for the carry; this prevents inserted v_add from killing VCC; the _e64 version doesn't accept a literal in its encoding, so we need to introduce a mov instr as well to get the imm into a register.
- Change pass name to "SI Load Store Optimizer"; this removes the '/', which complicates scripts.
Differential Revision: https://reviews.llvm.org/D42124
llvm-svn: 323153
Summary:
This patch implements d16 support for image load, image store and image sample intrinsics.
Reviewers:
Matt, Brian.
Differential Revision:
https://reviews.llvm.org/D3991
llvm-svn: 322903
Summary:
A recent change
321556: AMDGPU: Remove mayLoad/hasSideEffects from MIMG stores
can allow the machine instruction scheduler to move an image store past
an image load using the same descriptor.
V2: Fixed by marking image ops as mayAlias and isAliased. This may be
overly conservative, and we may need to revisit.
V3: Reverted test change done on 321556.
Reviewers: arsenm, nhaehnle, dstuttard
Subscribers: llvm-commits, t-tye, yaxunl, wdng, kzhuravl
Differential Revision: https://reviews.llvm.org/D41969
llvm-svn: 322419
While updating clang tests for having clang set dso_local I noticed
that:
- There are *a lot* of tests to update.
- Many of the updates are redundant.
They are redundant because a GV is "obviously dso_local". This patch
starts formalizing that a bit by requiring that internal and private
GVs be dso_local too. Since they all are, we don't have to print
dso_local to the textual representation, making it a bit more compact
and easier to read.
llvm-svn: 322317
Planning to add support for named vregs. This puts is in a conundrum since
physregs are named as well. To rectify this we need to use a sigil other than
'%' for physregs in MIR. We've settled on using '$' for physregs but first we
must repurpose it from external symbols using it, which is what this commit is
all about. We think '&' will have familiar semantics for C/C++ users.
llvm-svn: 322146
Summary:
In the case of an fp_extend of v1f16 to v1f32 where the v1f16 is the
result of a bitcast from i16, avoid creating an illegal fp16_to_fp where
the input is not a vector and the result is a v1f32.
V2: The fix is now to avoid vector scalarization creating a v1->scalar
bitcast.
Reviewers: srhines, t.p.northover
Subscribers: nhaehnle, llvm-commits, dstuttard, t-tye, yaxunl, wdng, kzhuravl, arsenm
Differential Revision: https://reviews.llvm.org/D41126
llvm-svn: 322120
Summary:
I had a case where multiple nested uniform ifs resulted in code that did
v_cmp comparisons, combining the results with s_and_b64, s_or_b64 and
s_xor_b64 and using the resulting mask in s_cbranch_vccnz, without first
ensuring that bits for inactive lanes were clear.
There was already code for inserting an "s_and_b64 vcc, exec, vcc" to
clear bits for inactive lanes in the case that the branch is instruction
selected as s_cbranch_scc1 and is then changed to s_cbranch_vccnz in
SIFixSGPRCopies. I have added the same code into SILowerControlFlow for
the case that the branch is instruction selected as s_cbranch_vccnz.
This de-optimizes the code in some cases where the s_and is not needed,
because vcc is the result of a v_cmp, or multiple v_cmp instructions
combined by s_and/s_or. We should add a pass to re-optimize those cases.
Reviewers: arsenm, kzhuravl
Subscribers: wdng, yaxunl, t-tye, llvm-commits, dstuttard, timcorringham, nhaehnle
Differential Revision: https://reviews.llvm.org/D41292
llvm-svn: 322119
Since register classes and banks are already printed with the register
definition, don't print it at the end of every instruction anymore.
This follows MIR in this regard and is another step to the unification
of the two formats.
llvm-svn: 322086
The work order was changed in r228186 from SCC order
to RPO with an arbitrary sorting function. The sorting
function attempted to move inner loop nodes earlier. This
was was apparently relying on an assumption that every block
in a given loop / the same loop depth would be seen before
visiting another loop. In the broken testcase, a block
outside of the loop was encountered before moving onto
another block in the same loop. The testcase would then
structurize such that one blocks unconditional successor
could never be reached.
Revert to plain RPO for the analysis phase. This fixes
detecting edges as backedges that aren't really.
The processing phase does use another visited set, and
I'm unclear on whether the order there is as important.
An arbitrary order doesn't work, and triggers some infinite
loops. The reversed RPO list seems to work and is closer
to the order that was used before, minus the arbitary
custom sorting.
A few of the changed tests now produce smaller code,
and a few are slightly worse looking.
llvm-svn: 321751
The test needs to be changed; it was exercising UB and that likely wasn't the intent of the test author. I simply removed the checks because I have absolutely no idea what this test was trying to accomplish. With multiple check patterns, no explanation, and no familiarity on my part with the ISA a true fix is going to have to come from someone familiar with the target.
llvm-svn: 321591
The test in question was checking for a particular intepretation of undefined behavior. Relax the test to check that we simply don't crash.
Sorry for the breakage, I don't generally build AMDGPU locally and just saw the failure this morning.
llvm-svn: 321589
Two issues were found about machine inst scheduler when compiling ProRender
with -g for amdgcn target:
GCNScheduleDAGMILive::schedule tries to update LiveIntervals for DBG_VALUE, which it
should not since DBG_VALUE is not mapped in LiveIntervals.
when DBG_VALUE is the last instruction of MBB, ScheduleDAGInstrs::buildSchedGraph and
ScheduleDAGMILive::scheduleMI does not move RPTracker properly, which causes assertion.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D41132
llvm-svn: 320650
Summary:
Add isRenamable() predicate to MachineOperand. This predicate can be
used by machine passes after register allocation to determine whether it
is safe to rename a given register operand. Register operands that
aren't marked as renamable may be required to be assigned their current
register to satisfy constraints that are not captured by the machine
IR (e.g. ABI or ISA constraints).
Reviewers: qcolombet, MatzeB, hfinkel
Subscribers: nemanjai, mcrosier, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D39400
llvm-svn: 320503
-amdgpu-waitcnt-forcezero={1|0} Force all waitcnt instrs to be emitted as s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
-amdgpu-waitcnt-forceexp=<n> Force emit a s_waitcnt expcnt(0) before the first <n> instrs
-amdgpu-waitcnt-forcelgkm=<n> Force emit a s_waitcnt lgkmcnt(0) before the first <n> instrs
-amdgpu-waitcnt-forcevm=<n> Force emit a s_waitcnt vmcnt(0) before the first <n> instrs
Differential Revision: https://reviews.llvm.org/D40091
llvm-svn: 320084
Surprisingly SIOptimizeExecMaskingPreRA can infinite loop
in some case with DBG_VALUE. Most tests using dbg_value are
run at -O0, so don't run this pass. This seems to only
happen when the value argument is undef.
llvm-svn: 319808
This calls handleMove with a DBG_VALUE instruction,
which isn't tracked by LiveIntervals. I'm not sure
this is the correct place to fix this. The generic
scheduler seems to have more deliberate region
selection that skips dbg_value.
The test is also really hard to reduce. I haven't been able
to figure out what exactly causes this particular case to
try moving the dbg_value.
llvm-svn: 319732
It's not implemented.
Passing +fp64-fp16-denormal feature enables fp64 even on asics that don't support it
v2: fix hasFP64 query
Differential Revision: https://reviews.llvm.org/D39931
llvm-svn: 319709
Move the entire optimization to one place. Before it was possible
to adjust dmask without changing the register class of the output
instruction, since they were done in separate places. Fix all
lane sizes and move all of the optimization into the DAG folding.
llvm-svn: 319705
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.
The MIR printer prints the IR name of a MBB only for block definitions.
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix
Differential Revision: https://reviews.llvm.org/D40422
llvm-svn: 319665
SelectionDAGISel::LowerArguments assumes sret addr space is 0, which is
not true for amdgcn---amdgiz target.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D40255
llvm-svn: 319630
Two issues found when doing codegen for splitting vector with non-zero alloca addr space:
DAGTypeLegalizer::SplitVecRes_INSERT_VECTOR_ELT/SplitVecOp_EXTRACT_VECTOR_ELT uses dummy pointer info for creating
SDStore. Since one pointer operand contains multiply and add, InferPointerInfo is unable to
infer the correct pointer info, which ends up with a dummy pointer info for the target to lower
store and results in isel failure. The fix is to introduce MachinePointerInfo::getUnknownStack to
represent MachinePointerInfo which is known in alloca address space but without other information.
TargetLowering::getVectorElementPointer uses value type of pointer in addr space 0 for
multiplication of index and then add it to the pointer. However the pointer may be in an addr
space which has different size than addr space 0. The fix is to use the pointer value type for
index multiplication.
Differential Revision: https://reviews.llvm.org/D39758
llvm-svn: 319622
output
As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.
Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.
Differential Revision: https://reviews.llvm.org/D40421
llvm-svn: 319445
As part of the unification of the debug format and the MIR format, avoid
printing "vreg" for virtual registers (which is one of the current MIR
possibilities).
Basically:
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/%vreg([0-9]+)/%\1/g"
* grep -nr '%vreg' . and fix if needed
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/ vreg([0-9]+)/ %\1/g"
* grep -nr 'vreg[0-9]\+' . and fix if needed
Differential Revision: https://reviews.llvm.org/D40420
llvm-svn: 319427
GFX9 does not enable bounds checking for the resource descriptors
used for private access, so it should be OK to use vaddr with
a potentially negative value.
llvm-svn: 319393
GFX9 stopped using m0 for most DS instructions. Select
a different instruction without the use. I think this will
be less error prone than trying to manually maintain m0
uses as needed.
llvm-svn: 319270
As part of the unification of the debug format and the MIR format,
always print registers as lowercase.
* Only debug printing is affected. It now follows MIR.
Differential Revision: https://reviews.llvm.org/D40417
llvm-svn: 319187
This test needs to be manually updated since it is difficult to do it with script.
Addr space 6 to 23 are only used by r600, therefore only check them for r600.
Differential Revision: https://reviews.llvm.org/D40117
llvm-svn: 319092
Summary:
Now that store-merge is only generates type-safe stores, do a second
pass just before instruction selection to allow lowered intrinsics to
be merged as well.
Reviewers: jyknight, hfinkel, RKSimon, efriedma, rnk, jmolloy
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33675
llvm-svn: 319036
AMDGPU backend errors with "unsupported call to function" upon
encountering a call to llvm.log{,10}.{f16,f32} intrinsics. This patch
adds custom lowering to avoid that error on both R600 and SI.
Reviewers: arsenm, jvesely
Subscribers: tstellar
Differential Revision: https://reviews.llvm.org/D29942
llvm-svn: 319025
SITargetLowering::LowerCall uses dummy pointer info for byval argument, which causes
flat load instead of buffer load.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D40040
llvm-svn: 318844
Summary:
This bug seems to have gone unnoticed because critical cases with LDS
instructions are eliminated by the peephole optimizer.
However, equivalent situations arise with buffer loads and stores
as well, so this fixes regressions since r317751 ("AMDGPU: Merge
S_BUFFER_LOAD_DWORD_IMM into x2, x4").
Fixes at least:
KHR-GL45.shader_storage_buffer_object.basic-operations-case1-cs
KHR-GL45.cull_distance.functional
piglit tes-input-gl_ClipDistance.shader_test
... and probably more
Change-Id: I0e371536288eb8e6afeaa241a185266fd45d129d
Reviewers: arsenm, mareko, rampitec
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D40303
llvm-svn: 318829
DAGTypeLegalizer::SplitInteger uses default pointer size as shift amount constant type,
which causes less performant ISA in amdgcn---amdgiz target since the default pointer
type is i64 whereas the desired shift amount type is i32.
This patch fixes that by using TLI.getScalarShiftAmountTy in DAGTypeLegalizer::SplitInteger.
The X86 change is necessary since splitting i512 requires shifting amount of 256, which
cannot be held by i8.
Differential Revision: https://reviews.llvm.org/D40148
llvm-svn: 318727
Manually update test r600.amdgpu-alias-analysis.ll for amdgiz environment
since it cannot be done by script.
The two pointers are swapped in the output because PrintResults in
AliasAnalysisEvaluator.cpp sorts the strings obtained from printAsOperand
before printing them.
Differential Revision: https://reviews.llvm.org/D40131
llvm-svn: 318660
This is mostly moving VMEM clause breaking into
the hazard recognizer. Also move another hazard
currently handled in the waitcnt pass.
Also stops breaking clauses unless xnack is enabled.
llvm-svn: 318557
llvm.invariant.group.barrier may accept pointers to arbitrary address space.
This patch let it accept pointers to i8 in any address space and returns
pointer to i8 in the same address space.
Differential Revision: https://reviews.llvm.org/D39973
llvm-svn: 318413
SelectionDAGBuilder::visitAlloca assumes alloca address space is 0, which is
incorrect for triple amdgcn---amdgiz and causes isel failure.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D40095
llvm-svn: 318392
processDbgDeclares assumes pointer size is the same for different addr spaces.
It uses pointer size for addr space 0 for all pointers, which causes assertion
in stripAndAccumulateInBoundsConstantOffsets for amdgcn---amdgiz since
pointer in addr space 5 has different size than in addr space 0.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D40085
llvm-svn: 318370
Use VOP3 add/addc like usual.
This has some tradeoffs. Inline immediates fold
a little better, but other constants are worse off.
SIShrinkInstructions could be made smarter to handle
these cases.
This allows us to avoid selecting scalar adds where we
need to track the carry in scc and replace its users.
This makes it easier to use the carryless VALU adds.
llvm-svn: 318340
Matt Arsenault