Commit Graph

12 Commits

Author SHA1 Message Date
Fangrui Song 306370be0b [AArch64] Fix namespace issue. NFC 2021-05-06 11:16:07 -07:00
Bradley Smith 62e9c7601a [AArch64][SVE] Remove unused function missed from D101302
The functionality in SVEIntrinsicOpts::isReinterpretToSVBool was moved in
D101302, however the original now unused function was not removed (NFC).

Differential Revision: https://reviews.llvm.org/D101642
2021-04-30 16:57:09 +01:00
Bradley Smith c8f20ed448 [AArch64][SVE] Move convert.{from,to}.svbool optimization into InstCombine
As part of this the ptrue coalescing done in SVEIntrinsicOpts has been
modified to not introduce redundant converts, since the convert removal
will no longer run after that optimisation to clean up.

Differential Revision: https://reviews.llvm.org/D101302
2021-04-29 12:17:42 +01:00
Jun Ma b0db2dbc29 [AArch64][SVEIntrinsicOpts] Optimize tbl+dup into dup+extractelement
Differential Revision: https://reviews.llvm.org/D99412
2021-03-30 10:35:08 +08:00
Joe Ellis 14bd44edc6 [AArch64][SVEIntrinsicOpts] Factor out redundant SVE mul/fmul intrinsics
This commit implements an IR-level optimization to eliminate idempotent
SVE mul/fmul intrinsic calls. Currently, the following patterns are
captured:

    fmul  pg  (dup_x  1.0)  V  =>  V
    mul   pg  (dup_x  1)    V  =>  V

    fmul  pg  V  (dup_x  1.0)  =>  V
    mul   pg  V  (dup_x  1)    =>  V

    fmul  pg  V  (dup  v  pg  1.0)  =>  V
    mul   pg  V  (dup  v  pg  1)    =>  V

The result of this commit is that code such as:

    1  #include <arm_sve.h>
    2
    3  svfloat64_t foo(svfloat64_t a) {
    4    svbool_t t = svptrue_b64();
    5    svfloat64_t b = svdup_f64(1.0);
    6    return svmul_m(t, a, b);
    7  }

will lower to a nop.

This commit does not capture all possibilities; only the simple cases
described above. There is still room for further optimisation.

Differential Revision: https://reviews.llvm.org/D98033
2021-03-16 14:50:17 +00:00
Joe Ellis 3d257fde75 [AArch64][SVE] Coalesce ptrue instrinsic calls where possible
It is possible to eliminate redundant calls to the SVE ptrue intrinsic.
For example: suppose that we have two SVE ptrue intrinsic calls P1 and
P2. If P1 is at least as wide as P2, then P2 can be written as a
reinterpret P1 using the SVE reinterpret intrinsics.

Coalescing ptrue intrinsics can result in fewer ptrue instructions in
the codegen, and is conducive to better analysis further down the line.

This commit extends the aarch64-sve-intrinsic-opts pass to support
coalescing ptrue intrisic calls.

Reviewed By: david-arm

Differential Revision: https://reviews.llvm.org/D94230
2021-02-05 10:43:28 +00:00
Joe Ellis 3122c66aee [AArch64][SVE] Remove chains of unnecessary SVE reinterpret intrinsics
This commit extends SVEIntrinsicOpts::optimizeConvertFromSVBool to
identify and remove longer chains of redundant SVE reintepret
intrinsics. For example, the following chain of redundant SVE
reinterprets is now recognised as redundant:

    %a = <vscale x 2 x i1>
    %1 = <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool(<vscale x 2 x i1> %a)
    %2 = <vscale x 4 x i1> @llvm.aarch64.sve.convert.from.svbool(<vscale x 16 x i1> %1)
    %3 = <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool(<vscale x 4 x i1> %2)
    %4 = <vscale x 4 x i1> @llvm.aarch64.sve.convert.from.svbool(<vscale x 16 x i1> %3)
    %5 = <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool(<vscale x 4 x i1> %4)
    %6 = <vscale x 2 x i1> @llvm.aarch64.sve.convert.from.svbool(<vscale x 16 x i1> %5)
    ret <vscale x 2 x i1> %6

and will be replaced with:

    ret <vscale x 2 x i1> %a

Eliminating these can sometimes mean emitting fewer unnecessary
loads/stores when lowering to assembly.

Differential Revision: https://reviews.llvm.org/D94074
2021-01-13 09:44:09 +00:00
Simon Pilgrim 037b058e41 [AArch64] SVEIntrinsicOpts - use range loop and cast<> instead of dyn_cast<> for dereferenced pointer. NFCI.
Don't directly dereference a dyn_cast<> - use cast<> so we assert for the correct type.

Also, simplify the for loop to a range loop.

Fixes clang static analyzer warning.
2021-01-07 14:21:55 +00:00
David Sherwood 6c7957c990 [SVE] Fix bug in SVEIntrinsicOpts::optimizePTest
The code wasn't taking into account that the two operands
passed to ptest could be identical and was trying to erase
them twice.

Differential Revision: https://reviews.llvm.org/D85892
2020-08-14 07:57:21 +01:00
Arthur Eubanks 2a672767cc Prefix some AArch64/ARM passes with "aarch64-"/"arm-"
For consistency with other target specific passes.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D84560
2020-07-27 11:00:39 -07:00
Sander de Smalen 3d9b53706f [SVEIntrinsicOpts] NFC: Remove unused isReinterpretFromBool for no-assert builds
isReinterpretFromBool's only use is in an assert, which causes a warning that the
function is defined but not used in no-assert builds.
2020-04-21 09:49:22 +01:00
Kerry McLaughlin 36c76de678 [AArch64][SVE] Add a pass for SVE intrinsic optimisations
Summary:
Creates the SVEIntrinsicOpts pass. In this patch, the pass tries
to remove unnecessary reinterpret intrinsics which convert to
and from svbool_t (llvm.aarch64.sve.convert.[to|from].svbool)

For example, the reinterprets below are redundant:

  %1 = call <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool.nxv4i1(<vscale x 4 x i1> %a)
  %2 = call <vscale x 4 x i1> @llvm.aarch64.sve.convert.from.svbool.nxv4i1(<vscale x 16 x i1> %1)

The pass also looks for ptest intrinsics and phi instructions where
the operands are being needlessly converted to and from svbool_t.

Reviewers: sdesmalen, andwar, efriedma, cameron.mcinally, c-rhodes, rengolin

Reviewed By: efriedma

Subscribers: mgorny, tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, danielkiss, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D76078
2020-04-14 10:41:49 +01:00