In some cases Clang does not perform merging of instructions AND and TST (aka
ANDS xzr).
Example:
tst x2, x1
and x3, x2, x1
to:
ands x3, x2, x1
This patch add such merging during instruction selection: when AND is replaced
with ANDS instruction in LowerSELECT_CC, all users of AND also should be
changed for using this ANDS instruction
Short discussion on mailing list:
http://llvm.1065342.n5.nabble.com/llvm-dev-ARM-Peephole-optimization-instructions-tst-add-tp133109.html
Patch by Pavel Kosov.
Differential Revision: https://reviews.llvm.org/D71701
These tests generate two nodes that are identical except for the
metadata that indicates their exception behavior. The nodes get
CSEd by SelectionDAG, but the nofpexcept flag is being set based
only on the fpexcept.ignore node being created last.
We need to detect this case and intersect the flags similar to
what is already done with fast math flags.
Since all types <32b on gpr end up being assigned gpr32 regclasses, we can end
up with PHIs here which try to select between a gpr32 and an fpr16. Ideally RBS
shouldn't be selecting heterogenous regbanks for operands if possible, but we
still need to be able to deal with it here.
To fix this, if we have a gpr-bank operand < 32b in size and at least one other
operand is on the fpr bank, then we add cross-bank copies to homogenize the
operand banks. For simplicity the bank that we choose to settle on is whatever
bank the def operand has. For example:
%endbb:
%dst:gpr(s16) = G_PHI %in1:gpr(s16), %bb1, %in2:fpr(s16), %bb2
=>
%bb2:
...
%in2_copy:gpr(s16) = COPY %in2:fpr(s16)
...
%endbb:
%dst:gpr(s16) = G_PHI %in1:gpr(s16), %bb1, %in2_copy:gpr(s16), %bb2
Differential Revision: https://reviews.llvm.org/D75086
This is a small pet peeve from me. This change makes sure the AVR backend uses
the correct private label prefix (.L) so that private labels are hidden in
avr-objdump.
Example code:
define i8 @foo(i1 %cond) {
br i1 %cond, label %then, label %else
then:
ret i8 3
else:
ret i8 5
}
When compiling this:
llc -march=avr -filetype=obj -o test.o test.ll
and then dumping it:
avr-objdump -d test.o
You would previously get an ugly temporary label:
00000000 <foo>:
0: 81 70 andi r24, 0x01 ; 1
2: 80 30 cpi r24, 0x00 ; 0
4: f9 f3 breq .-2 ; 0x4 <foo+0x4>
6: 83 e0 ldi r24, 0x03 ; 3
8: 08 95 ret
0000000a <LBB0_2>:
a: 85 e0 ldi r24, 0x05 ; 5
c: 08 95 ret
This patch fixes that, the output is now:
00000000 <foo>:
0: 81 70 andi r24, 0x01 ; 1
2: 80 30 cpi r24, 0x00 ; 0
4: 01 f0 breq .+0 ; 0x6 <foo+0x6>
6: 83 e0 ldi r24, 0x03 ; 3
8: 08 95 ret
a: 85 e0 ldi r24, 0x05 ; 5
c: 08 95 ret
Note that as you can see the breq operand is different. However it is
still the same after linking:
4: 11 f0 breq .+4
Differential Revision: https://reviews.llvm.org/D75124
- Mark memory access for bool vectors as disallowed in target lowering.
This will prevent combining bitcasts of bool vectors with stores.
- Replace the actual bitcasting code with a faster version.
- Handle casting of v16i1 to i16.
This may inhibit vector narrowing in general, but there's
already an inconsistency in the way that we deal with this
pattern as shown by the test diff.
We may want to add a dedicated function for narrowing fneg.
It's often folded into some other op, so moving it away from
other math ops may cause regressions that we would not see
for normal binops.
See D73978 for more details.
Summary:
This commit adds the predicated MVE intrinsics for the same set of
unary operations that I added in their unpredicated forms in
* D74333 (vrint)
* D74334 (vrev)
* D74335 (vclz, vcls)
* D74336 (vmovl)
* D74337 (vmovn)
but since the predicated versions are a lot more similar to each
other, I've kept them all together in a single big patch. Everything
here is done in the standard way we've been doing other predicated
operations: an IR intrinsic called `@llvm.arm.mve.foo.predicated` and
some isel rules that match that alongside whatever they accept for the
unpredicated version of the same instruction.
In order to write the isel rules conveniently, I've refactored the
existing isel rules for the affected instructions into multiclasses
parametrised by a vector-type class, in the usual way. All those
refactorings are intended to leave the existing isel rules unchanged:
the only difference should be that new ones for the predicated
intrinsics are introduced.
The only tiny infrastructure change I needed in this commit was to
change the implementation of `IntrinsicMX` in `arm_mve_defs.td` so
that the records it defines are anonymous rather than named (and use
`NameOverride` to set the output intrinsic name), which allows me to
call it twice in two multiclasses with the same `NAME` without a
tablegen-time error.
Reviewers: dmgreen, MarkMurrayARM, miyuki, ostannard
Reviewed By: MarkMurrayARM
Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D75165
Allow all ExternalSymbolSDNode on AIX, and rely on the linker error to find
symbols which we don't have definitions from any library/compiler-rt.
Differential Revision: https://reviews.llvm.org/D75075
Summary:
The old code made some incorrect assumptions about the order in which
basic blocks are laid out in a function. This could lead to incorrect
early-exits, especially when kills occurred inside of loops.
The new approach is to check whether the point where the conditional
kill occurs dominates all reachable code. If that is the case, there
cannot be any other threads in the wave that are waiting to rejoin
at a later point in the CFG, i.e. if exec=0 at that point, then all
threads really are dead and we can exit the wave.
Make some other minor cleanups to the pass while we're at it.
v2: preserve the dominator tree
Reviewers: arsenm, cdevadas, foad, critson
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74908
Change-Id: Ia0d2b113ac944ad642d1c622b6da1b20aa1aabcc
Summary:
Implements the following intrinsics:
- @llvm.aarch64.sve.bdep.x
- @llvm.aarch64.sve.bext.x
- @llvm.aarch64.sve.bgrp.x
- @llvm.aarch64.sve.tbl2
- @llvm.aarch64.sve.tbx
The SelectTableSVE2 function in this patch is used to select the TBL2
intrinsic & ensures that the vector registers allocated are consecutive.
Reviewers: sdesmalen, andwar, dancgr, cameron.mcinally, efriedma, rengolin
Reviewed By: efriedma
Subscribers: tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, cfe-commits, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74912
Summary:
The patch D62993 : `[PowerPC] Emit scalar min/max instructions with unsafe fp math`
has modified the functionality when `Subtarget.hasP9Vector() && (!HasNoInfs || !HasNoNaNs)`,
this modification is not expected.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D74701
This node reads the rounding control which means it needs to be ordered properly with operations that change the rounding control. So it needs to be chained to maintain order.
This patch adds a chain input and output to the node and connects it to the chain in SelectionDAGBuilder. I've update all in-tree targets to connect their chain through their lowering code.
Differential Revision: https://reviews.llvm.org/D75132
Summary:
Removes patterns that were not doing useful work, changes the
default extract instructions to be the unsigned versions now that
they are enabled by default, fixes PR44988, and adds tests for
sext_inreg lowering.
Reviewers: aheejin
Reviewed By: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75005
Summary:
Implements the following intrinsics:
* llvm.aarch64.sve.convert.to.svbool
* llvm.aarch64.sve.convert.from.svbool
For converting the ACLE svbool_t type (<n x 16 x i1>) to and from the
other predicate types: <n x 8 x i1>, <n x 4 x i1> and <n x 2 x i1>.
Reviewers: sdesmalen, kmclaughlin, efriedma, dancgr, rengolin
Reviewed By: sdesmalen, efriedma
Subscribers: tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74471
The current set of custom combines are only really useful after
legalization, so move them there. There is a lot of overlap in the
boilerplate here, but I think we do want a pretty different set of
combines before and after legalize. I think we will want a lot of
overlap between the post-legalize and a post-regbankselect combiner.
Summary:
Terminators in LLVM aren't prohibited from returning values. This means that
the "callbr" instruction, which is used for "asm goto", can support "asm goto
with outputs."
This patch removes all restrictions against "callbr" returning values. The
heavy lifting is done by the code generator. The "INLINEASM_BR" instruction's
a terminator, and the code generator doesn't allow non-terminator instructions
after a terminator. In order to correctly model the feature, we need to copy
outputs from "INLINEASM_BR" into virtual registers. Of course, those copies
aren't terminators.
To get around this issue, we split the block containing the "INLINEASM_BR"
right before the "COPY" instructions. This results in two cheats:
- Any physical registers defined by "INLINEASM_BR" need to be marked as
live-in into the block with the "COPY" instructions. This violates an
assumption that physical registers aren't marked as "live-in" until after
register allocation. But it seems as if the live-in information only
needs to be correct after register allocation. So we're able to get away
with this.
- The indirect branches from the "INLINEASM_BR" are moved to the "COPY"
block. This is to satisfy PHI nodes.
I've been told that MLIR can support this handily, but until we're able to
use it, we'll have to stick with the above.
Reviewers: jyknight, nickdesaulniers, hfinkel, MaskRay, lattner
Reviewed By: nickdesaulniers, MaskRay, lattner
Subscribers: rriddle, qcolombet, jdoerfert, MatzeB, echristo, MaskRay, xbolva00, aaron.ballman, cfe-commits, JonChesterfield, hiraditya, llvm-commits, rnk, craig.topper
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D69868
Changes the handling of odd breakdowns, and avoids using
G_EXTRACT/G_INSERT. Pad with undef to a wider size, and unmerge. Also
avoid introducing instructions for the fully undef components.
This is explicitly guaranteed in ARMARM. And it makes reasoning about
vectors easier: we can assume that if a vector operation is legal, the
corresponding scalar operation is also legal.
Differential Revision: https://reviews.llvm.org/D74993
Summary:
Function descriptor csect on AIX should be 4 byte align instead of 1 byte align.
Reviewer: daltenty
Differential Revision: https://reviews.llvm.org/D74974
Extends the existing support for spilling and restoring the condition
register to the linkage area for 32-bit targets, and enables for AIX.
Differential Revision: https://reviews.llvm.org/D74349
This adds infrastructure to print and parse MIR MachineOperand comments.
The motivation for the ARM backend is to print condition code names instead of
magic constants that are difficult to read (for human beings). For example,
instead of this:
dead renamable $r2, $cpsr = tEOR killed renamable $r2, renamable $r1, 14, $noreg
t2Bcc %bb.4, 0, killed $cpsr
we now print this:
dead renamable $r2, $cpsr = tEOR killed renamable $r2, renamable $r1, 14 /* CC::always */, $noreg
t2Bcc %bb.4, 0 /* CC:eq */, killed $cpsr
This shows that MachineOperand comments are enclosed between /* and */. In this
example, the EOR instruction is not conditionally executed (i.e. it is "always
executed"), which is encoded by the 14 immediate machine operand. Thus, now
this machine operand has /* CC::always */ as a comment. The 0 on the next
conditional branch instruction represents the equal condition code, thus now
this operand has /* CC:eq */ as a comment.
As it is a comment, the MI lexer/parser completely ignores it. The benefit is
that this keeps the change in the lexer extremely minimal and no target
specific parsing needs to be done. The changes on the MIPrinter side are also
minimal, as there is only one target hooks that is used to create the machine
operand comments.
Differential Revision: https://reviews.llvm.org/D74306
