Commit Graph

11 Commits

Author SHA1 Message Date
Simon Tatham 01aefae4a1 [ARM,MVE] Add an InstCombine rule permitting VPNOT.
Summary:
If a user writing C code using the ACLE MVE intrinsics generates a
predicate and then complements it, then the resulting IR will use the
`pred_v2i` IR intrinsic to turn some `<n x i1>` vector into a 16-bit
integer; complement that integer; and convert back. This will generate
machine code that moves the predicate out of the `P0` register,
complements it in an integer GPR, and moves it back in again.

This InstCombine rule replaces `i2v(~v2i(x))` with a direct complement
of the original predicate vector, which we can already instruction-
select as the VPNOT instruction which complements P0 in place.

Reviewers: ostannard, MarkMurrayARM, dmgreen

Reviewed By: dmgreen

Subscribers: kristof.beyls, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70484
2019-12-02 16:20:30 +00:00
Simon Tatham f4f77aa53e [ARM,MVE] Add InstCombine rules for pred_i2v / pred_v2i.
If you're writing C code using the ACLE MVE intrinsics that passes the
result of a vcmp as input to a predicated intrinsic, e.g.

  mve_pred16_t pred = vcmpeqq(v1, v2);
  v_out = vaddq_m(v_inactive, v3, v4, pred);

then clang's codegen for the compare intrinsic will create calls to
`@llvm.arm.mve.pred.v2i` to convert the output of `icmp` into an
`mve_pred16_t` integer representation, and then the next intrinsic
will call `@llvm.arm.mve.pred.i2v` to convert it straight back again.
This will be visible in the generated code as a `vmrs`/`vmsr` pair
that move the predicate value pointlessly out of `p0` and back into it again.

To prevent that, I've added InstCombine rules to remove round trips of
the form `v2i(i2v(x))` and `i2v(v2i(x))`. Also I've taught InstCombine
about the known and demanded bits of those intrinsics. As a result,
you now get just the generated code you wanted:

  vpt.u16 eq, q1, q2
  vaddt.u16 q0, q3, q4

Reviewers: ostannard, MarkMurrayARM, dmgreen

Reviewed By: dmgreen

Subscribers: kristof.beyls, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70313
2019-11-18 10:39:30 +00:00
David Bolvansky e80fcf0340 [SimplifyLibCalls] Mark known arguments with nonnull
Reviewers: efriedma, jdoerfert

Reviewed By: jdoerfert

Subscribers: ychen, rsmith, joerg, aaron.ballman, lebedev.ri, uenoku, jdoerfert, hfinkel, javed.absar, spatel, dmgreen, llvm-commits

Differential Revision: https://reviews.llvm.org/D53342

llvm-svn: 372091
2019-09-17 09:32:52 +00:00
David Bolvansky 39130314fe [SimplifyLibCalls] Add dereferenceable bytes from known callsites
Summary:
int mm(char *a, char *b) {
    return memcmp(a,b,16);
}

Currently:
define dso_local i32 @mm(i8* nocapture readonly %a, i8* nocapture readonly %b) local_unnamed_addr #1 {
entry:
  %call = tail call i32 @memcmp(i8* %a, i8* %b, i64 16)
  ret i32 %call
}

After patch:
define dso_local i32 @mm(i8* nocapture readonly %a, i8* nocapture readonly %b) local_unnamed_addr #1 {
entry:
  %call = tail call i32 @memcmp(i8* dereferenceable(16)  %a, i8* dereferenceable(16)  %b, i64 16)
  ret i32 %call
}




Reviewers: jdoerfert, efriedma

Reviewed By: jdoerfert

Subscribers: javed.absar, spatel, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66079

llvm-svn: 368657
2019-08-13 09:11:49 +00:00
Eric Christopher cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Alexandros Lamprineas 61f0ba1fcc [InstCombine, ARM] Convert vld1 to llvm load
Convert a vector load intrinsic into an llvm load instruction.
This is beneficial when the underlying object being addressed
comes from a constant, since we get constant-folding for free.

Differential Revision: https://reviews.llvm.org/D46273

llvm-svn: 333643
2018-05-31 12:19:18 +00:00
Alexandros Lamprineas 52457d33b2 [InstCombine, ARM, AArch64] Convert table lookup to shuffle vector
Turning a table lookup intrinsic into a shuffle vector instruction
can be beneficial. If the mask used for the lookup is the constant
vector {7,6,5,4,3,2,1,0}, then the back-end generates byte reverse
instructions instead.

Differential Revision: https://reviews.llvm.org/D46133

llvm-svn: 333550
2018-05-30 14:38:50 +00:00
Chad Rosier 274d72faad [InstCombine] Combine XOR and AES instructions on ARM/ARM64.
The ARM/ARM64 AESE and AESD instructions have a builtin XOR as the first step in
the instruction. Therefore, if the AES key is zero and the AES data was
previously XORed, it can be combined into a single instruction.

Differential Revision: https://reviews.llvm.org/D47239
Patch by Michael Brase!

llvm-svn: 333193
2018-05-24 15:26:42 +00:00
Justin Bogner 3c6fbad388 InstCombine: Move tests that use target intrinsics into subdirectories
Tests with target intrinsics are inherently target specific, so it
doesn't actually make sense to run them if we've excluded their
target.

llvm-svn: 302979
2017-05-13 05:39:46 +00:00
Sam Parker 214f7bf5cc Enable simplify libcalls for ARM PCS
Teach SimplifyLibcalls that in can treat functions annotated with
apcs, aapcs or aapcs_vfp like normal C functions if they only take
and return integer or pointer values, and the target is not iOS.

Differential Revision: https://reviews.llvm.org/D24453

llvm-svn: 281322
2016-09-13 12:10:14 +00:00