mflr is kind of expensive on Power version smaller than 10, so we should
schedule the store for the mflr's def away from mflr.
In epilogue, the expensive mtlr has no user for its def, so it doesn't
matter that the load and the mtlr are back-to-back.
Reviewed By: RolandF
Differential Revision: https://reviews.llvm.org/D137423
The LIT test cases were migrated with the script provided by
Nikita Popov. Due to the size of the change it is split into
several parts.
Reviewed By: nemanja, amyk, nikic, PowerPC
Differential Revision: https://reviews.llvm.org/D135470
This patch changes the PowerPC backend to generate VSX load/store instructions
for all vector loads/stores on Power8 and earlier (LE) instead of VMX
load/store instructions. The reason for this change is because VMX instructions
require the vector to be 16-byte aligned. So, a vector load/store will fail with
VMX instructions if the vector is misaligned. Also, `gcc` generates VSX
instructions in this situation which allow for unaligned access but require a
swap instruction after loading/before storing. This is not an issue for BE
because we already emit VSX instructions since no swap is required. And this is
not an issue on Power9 and up since we have access to `lxv[x]`/`stxv[x]` which
allow for unaligned access and do not require swaps.
This patch also delays the VSX load/store for LE combines until after
LegalizeOps to prioritize other load/store combines.
Reviewed By: #powerpc, stefanp
Differential Revision: https://reviews.llvm.org/D127309
This patch includes the following updates to the load/store refactoring effort introduced in D93370:
- Update various VSX patterns that use to "force" an XForm, to instead just XForm.
This allows the ability for the patterns to compute the most optimal addressing
mode (and to produce a DForm instruction when possible)
- Update pattern and test case for the LXVD2X/STXVD2X intrinsics
- Update LIT test cases that use to use the XForm instruction to use the DForm instruction
Differential Revision: https://reviews.llvm.org/D95115
This patch is the last one in backend to support fp128 type in
pre-POWER9 subtargets with VSX, removing temporary option and updating
remaining tests.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D92374
Summary: Some constants can be handled with less instructions than our current results. And it seems our original approach is not very easy to extend. Therefore this patch proposes to materialize all 64-bit constants by enumerated patterns.
I traversed almost all constants to verified the functionality of these pattens. A traversed comparison of the number of instructions used by the original method and the new method has also been completed, where no degradation was caused by this patch. This patch also passed Bootstrap test and SPEC test.
Improvements of this patch are shown in llvm/test/CodeGen/PowerPC/constants-i64.ll
Reviewed By: steven.zhang, stefanp
Differential Revision: https://reviews.llvm.org/D92089
Vector types, quadword integers and f128 currently cannot be handled in
FastISel. We did not skip f128 type in lowering arguments, which causes
a crash. This patch will fix it.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D90206
tryLatency compares two sched candidates. For the top zone it prefers
the one with lesser depth, but only if that depth is greater than the
total latency of the instructions we've already scheduled -- otherwise
its latency would be hidden and there would be no stall.
Unfortunately it only tests the depth of one of the candidates. This can
lead to situations where the TopDepthReduce heuristic does not kick in,
but a lower priority heuristic chooses the other candidate, whose depth
*is* greater than the already scheduled latency, which causes a stall.
The fix is to apply the heuristic if the depth of *either* candidate is
greater than the already scheduled latency.
All this also applies to the BotHeightReduce heuristic in the bottom
zone.
Differential Revision: https://reviews.llvm.org/D72392
When we call checkResourceLimit in bumpCycle or bumpNode, and we
know the resource count has just reached the limit (the equations
are equal). We should return true to mark that we are resource
limited for next schedule, or else we might continue to schedule
in favor of latency for 1 more schedule and create a schedule that
actually overbook the resource.
When we call checkResourceLimit to estimate the resource limite before
scheduling, we don't need to return true even if the equations are
equal, as it shouldn't limit the schedule for it .
Differential Revision: https://reviews.llvm.org/D62345
llvm-svn: 362805
When switched to the MI scheduler for P9, the hardware is modeled as out of order.
However, inside the MI Scheduler algorithm, we still use the in-order scheduling model
as the MicroOpBufferSize isn't set. The MI scheduler take it as the hw cannot buffer
the op. So, only when all the available instructions issued, the pending instruction
could be scheduled. That is not true for our P9 hw in fact.
This patch is trying to enable the Out-of-Order scheduling model. The buffer size 44 is
picked from the P9 hw spec, and the perf test indicate that, its value won't hurt the cpu2017.
With this patch, there are 3 specs improved over 3% and 1 spec deg over 3%. The detail is as follows:
x264_r: +6.95%
cactuBSSN_r: +6.94%
lbm_r: +4.11%
xz_r: -3.85%
And the GEOMEAN for all the C/C++ spec in spec2017 is about 0.18% improved.
Reviewer: Nemanjai
Differential Revision: https://reviews.llvm.org/D55810
llvm-svn: 350285
This patch will address using the xscpsgndp instruction to copy floating point
scalar registers instead of the xxlor (specifically XXLORf) instruction that is
currently used. Additionally, this patch of utilizing xscpsgndp will apply to
P9, while pre-P9 will still use xxlor.
Patch by amyk
Differential Revision: https://reviews.llvm.org/D50004
llvm-svn: 340643
Optimize code sequences for integer conversion to fp128 when the integer is a result of:
* float->int
* float->long
* double->int
* double->long
Differential Revision: https://reviews.llvm.org/D48429
llvm-svn: 336316
This patch enable parameter passing and return by value for float128 types.
Passing aggregate/union which contain float128 members will be submitted in
subsequent patches.
Differential Revision: https://reviews.llvm.org/D47552
llvm-svn: 336306
