Testing for specific CPUs has a number of problems, better use subtarget
features:
- When some tweak is added for a specific CPU it is often desirable for
the next version of that CPU as well, yet we often forget to add it.
- It is hard to keep track of checks scattered around the target code;
Declaring all target specifics together with the CPU in the tablegen
file is a clear representation.
- Subtarget features can be tweaked from the command line.
To discourage people from using CPU checks in the future I removed the
isCortexXX(), isCyclone(), ... functions. I added an getProcFamily()
function for exceptional circumstances but made it clear in the comment
that usage is discouraged.
Reformat feature list in AArch64.td to have 1 feature per line in
alphabetical order to simplify merging and sorting for out of tree
tweaks.
No functional change intended.
Differential Revision: http://reviews.llvm.org/D20762
llvm-svn: 271555
Summary:
As this optimization converts two loads into one load with two shift instructions,
it could potentially hurt performance if a loop is arithmetic operation intensive.
Reviewers: t.p.northover, mcrosier, jmolloy
Subscribers: evandro, jmolloy, aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D20172
llvm-svn: 270251
Summary: This change refactors to decouple the zero store promotion from the narrow ld merge and add a flag (enable-narrow-ld-merge=true) to control the narrow ld merge optimization.
Reviewers: jmolloy, t.p.northover, mcrosier
Subscribers: aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D19885
llvm-svn: 268744
Summary:
This adds the same checks that were added in r264593 to all
target-specific passes that run after register allocation.
Reviewers: qcolombet
Subscribers: jyknight, dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D18525
llvm-svn: 265313
Summary:
This change will handle missing store pair opportunity where the first store
instruction stores zero followed by the non-zero store. For example, this change
will convert :
str wzr, [x8]
str w1, [x8, #4]
into:
stp wzr, w1, [x8]
Reviewers: jmolloy, t.p.northover, mcrosier
Subscribers: flyingforyou, aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18570
llvm-svn: 265021
This patch adds unscaled loads and sign-extend loads to the TII
getMemOpBaseRegImmOfs API, which is used to control clustering in the MI
scheduler. This is done to create more opportunities for load pairing. I've
also added the scaled LDRSWui instruction, which was missing from the scaled
instructions. Finally, I've added support in shouldClusterLoads for clustering
adjacent sext and zext loads that too can be paired by the load/store optimizer.
Differential Revision: http://reviews.llvm.org/D18048
llvm-svn: 263819
This patch allows the mixing of scaled and unscaled load/stores to form
load/store pairs.
This is a reapplication of r259812, which had an incorrect assert. The
test_stur_str_no_assert() test is a reduced version of the issue hit in
the AArch64 self-host.
PR24465
llvm-svn: 260523
Summary:
Fix case where a pre-inc/dec load/store would not be formed if the
add/sub that forms the inc/dec part of the operation was the first
instruction in the block being examined.
Reviewers: mcrosier, jmolloy, t.p.northover, junbuml
Subscribers: aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D16785
llvm-svn: 260275
The logic to pair instructions and merge narrow instructions has become cloogy
and error prone. This patch beings to unravel these two similar, but distinct
optimizations.
llvm-svn: 260242
This only impacts the creation of pre-/post-index instructions. The bound was
set high enough such that it did not change code generation for SPEC200X.
llvm-svn: 259828
This patch allows the mixing of scaled and unscaled load/stores to form
load/store pairs.
PR24465
http://reviews.llvm.org/D12116
Many thanks to Ahmed and Michael for fixes and code review.
This is a reapplication of r246769 and r259790. The tramp3d failure was caused
by an incorrect refactoring in the patch. Specifically, we weren't always
properly clearing the SExtIdx flag.
llvm-svn: 259812
This patch allows the mixing of scaled and unscaled load/stores to form
load/store pairs.
PR24465
http://reviews.llvm.org/D12116
Many thanks to Ahmed and Michael for fixes and code review.
This is a reapplication of r246769, which was reverted in r246782 due to a
test-suite failure. I'm unable to reproduce the issue at this time.
llvm-svn: 259790
In the discussion on http://reviews.llvm.org/D15730, Andy pointed out we had a utility function for merging MMO lists. Since it turned we actually had two copies and there's another review in progress (http://reviews.llvm.org/D15230) which needs the same, extract it into a utility function and clean up the interfaces to make it easier to use with a MachineInstBuilder.
I introduced a pair here to track size and allocation together. I think we should probably move in the direction of the MachineOperandsRef helper class, but I'm leaving that for further work. I want to get the poison state introduced before I make major changes to the interface.
Differential Revision: http://reviews.llvm.org/D15757
llvm-svn: 256909
This is a recommit of r256004 which was reverted in r256160. The issue was the
incorrect promotion for half and byte loads transformed into mov instructions.
This fix will replace half and byte type loads only with bit field extracts.
Original commit message:
This change promotes load instructions which directly read from stored by
replacing them with mov instructions. If the store is wider than the load,
the load will be replaced with a bitfield extract.
For example :
STRWui %W1, %X0, 1
%W0 = LDRHHui %X0, 3
becomes
STRWui %W1, %X0, 1
%W0 = UBFMWri %W1, 16, 31
llvm-svn: 256249