Commit Graph

34 Commits

Author SHA1 Message Date
Evandro Menezes 567f6c150d [AVR] Change limit type to match the argument type (NFC)
llvm-svn: 363832
2019-06-19 16:12:12 +00:00
Dylan McKay 04b418f246 [AVR] Expand 16-bit rotations during the legalization stage
In r356860, the legalization logic for BSWAP was modified to ISD::ROTL,
rather than the old ISD::{SHL, SRL, OR} nodes.

This works fine on AVR for 8-bit rotations, but 16-bit rotations are
currently unimplemented - they always trigger an assertion error in the
AVRExpandPseudoInsts pass ("RORW unimplemented").

This patch instructions the legalizer to expand 16-bit rotations into
the previous SHL, SRL, OR pattern it did previously.

This fixes the 'issue-cannot-select-bswap.ll' test. Interestingly, this
test failure seems flaky - it passes successfully on the avr-build-01
buildbot, but fails locally on my Arch Linux install.

llvm-svn: 362773
2019-06-07 06:55:00 +00:00
Dylan McKay 8a56d10a2f [AVR] Fix a typo - 's/analisys/analysis'
llvm-svn: 353987
2019-02-13 22:31:37 +00:00
Dylan McKay 5c23410fdf [AVR] Insert unconditional branch when inserting MBBs between blocks with fallthrough
This updates the AVR Select8/Select16 expansion code so that, when
inserting the two basic blocks for true and false conditions, any
existing fallthrough on the previous block is preserved.

Prior to this patch, if the block before the Select pseudo fell through
to the subsequent block, two new basic blocks would be inserted at the
prior fallthrough point, changing the fallthrough destination.

The predecessor or successor lists were not updated, causing the
BranchFolding pass at -O1 and above the rearrange basic blocks, causing
an infinite loop. Not to mention the unconditional fallthrough to the
true block is incorrect in of itself.

This patch modifies the Select8/16 expansion so that, if inserting true
and false basic blocks at a fallthrough point, the implicit branch is
preserved by means of an explicit, unconditional branch to the previous
fallthrough destination.

Thanks to Carl Peto for reporting this bug.

This fixes avr-rust bug https://github.com/avr-rust/rust/issues/123.

llvm-svn: 351721
2019-01-21 04:32:02 +00:00
Dylan McKay ce0ab06353 Revert "[AVR] Insert unconditional branch when inserting MBBs between blocks with fallthrough"
This reverts commit r351718.

Carl pointed out that the unit test could be improved.

This patch will be recommitted once the test is made more resilient.

llvm-svn: 351719
2019-01-21 02:46:13 +00:00
Dylan McKay 33acba43f0 [AVR] Insert unconditional branch when inserting MBBs between blocks with fallthrough
This updates the AVR Select8/Select16 expansion code so that, when
inserting the two basic blocks for true and false conditions, any
existing fallthrough on the previous block is preserved.

Prior to this patch, if the block before the Select pseudo fell through
to the subsequent block, two new basic blocks would be inserted at the
prior fallthrough point, changing the fallthrough destination.

The predecessor or successor lists were not updated, causing the
BranchFolding pass at -O1 and above the rearrange basic blocks, causing
an infinite loop. Not to mention the unconditional fallthrough to the
true block is incorrect in of itself.

This patch modifies the Select8/16 expansion so that, if inserting true
and false basic blocks at a fallthrough point, the implicit branch is
preserved by means of an explicit, unconditional branch to the previous
fallthrough destination.

Thanks to Carl Peto for reporting this bug.

This fixes avr-rust bug https://github.com/avr-rust/rust/issues/123.

llvm-svn: 351718
2019-01-21 02:44:09 +00:00
Dylan McKay 6afef286d9 [AVR] Fix codegen bug in 16-bit loads
Prior to this patch, the AVR::LDWRdPtr instruction was always lowered to
instructions of this pattern:

    ld  $GPR8, [PTR:XYZ]+
    ld  $GPR8, [PTR]+1

This has a problem; the [PTR] is incremented in-place once, but never
decremented.

Future uses of the same pointer will use the now clobbered value,
leading to the pointer being incorrect by an offset of one.

This patch modifies the expansion code of the LDWRdPtr pseudo
instruction so that the pointer variable is not silently clobbered in
future uses in the same live range.

Bug first reported by Keshav Kini.

Patch by Kaushik Phatak.

llvm-svn: 351673
2019-01-20 03:41:08 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Dylan McKay 7203e00b5e [AVR] Expand 8/16-bit multiplication to libcalls on MCUs that don't have hardware MUL
This change modifies the LLVM ISel lowering settings so that
8-bit/16-bit multiplication is expanded to calls into the compiler
runtime library if the MCU being targeted does not support
multiplication in hardware.

Before this, MUL instructions would be generated on CPUs like the
ATtiny85, triggering a CPU reset due to an illegal instruction at
runtime.

First raised in https://github.com/avr-rust/rust/issues/124.

llvm-svn: 351523
2019-01-18 06:10:41 +00:00
Dylan McKay 454258671d [AVR] Redefine the 'LSL' instruction as an alias of 'ADD'
The 'LSL Rd' instruction is equivalent to 'ADD Rd, Rd'.

llvm-svn: 341278
2018-09-01 12:23:00 +00:00
Dylan McKay 8b0f9d2e58 [AVR] Define the ROL instruction as an alias of ADC
The 'rol Rd' instruction is equivalent to 'adc Rd'.

This caused compile warnings from tablegen because of conflicting bits
shared between each instruction.

llvm-svn: 341275
2018-09-01 12:22:07 +00:00
Dylan McKay 6bc5d5c6db [AVR] Re-enable expansion of ADDE/ADDC/SUBE/SUBC in ISel
This was disabled in r333748, which broke four tests.

In the future, these need to be updated to UADDO/ADDCARRY or
USUBO/SUBCARRY.

llvm-svn: 338212
2018-07-29 11:38:36 +00:00
Dylan McKay a35ee70641 [AVR] Lower i128 divisions to runtime library calls
This patch adds i128 division support by instruction LLVM to lower
128-bit divisions to the __udivmodti4 and __divmodti4 rtlib functions.

This also adds test for 64-bit division and 128-bit division.

Patch by Peter Nimmervoll.

llvm-svn: 327814
2018-03-19 00:55:50 +00:00
Dylan McKay 05d3e41076 [AVR] Fix a lowering bug in AVRISelLowering.cpp
The parseFunctionArgs() method was directly reading the
arguments from a Function object, but is should have used the
arguments supplied by the SelectionDAGBuilder.

This was causing
the lowering code to only lower one argument, not two in some cases.

Thanks to @brainlag on GitHub for coming up with the working fix!

Patch-by: @brainlag on GitHub
llvm-svn: 325474
2018-02-19 08:28:38 +00:00
Matthias Braun f1caa2833f MachineFunction: Return reference from getFunction(); NFC
The Function can never be nullptr so we can return a reference.

llvm-svn: 320884
2017-12-15 22:22:58 +00:00
Dylan McKay 80463fe64d Relax unaligned access assertion when type is byte aligned
Summary:
This relaxes an assertion inside SelectionDAGBuilder which is overly
restrictive on targets which have no concept of alignment (such as AVR).

In these architectures, all types are aligned to 8-bits.

After this, LLVM will only assert that accesses are aligned on targets
which actually require alignment.

This patch follows from a discussion on llvm-dev a few months ago
http://llvm.1065342.n5.nabble.com/llvm-dev-Unaligned-atomic-load-store-td112815.html

Reviewers: bogner, nemanjai, joerg, efriedma

Reviewed By: efriedma

Subscribers: efriedma, cactus, llvm-commits

Differential Revision: https://reviews.llvm.org/D39946

llvm-svn: 320243
2017-12-09 06:45:36 +00:00
Dylan McKay 1446eedbc2 [AVR] Prefer BasicBlock::getIterator over Function::begin()
Thanks to Eli Friedman for the suggestion.

llvm-svn: 314182
2017-09-26 01:37:53 +00:00
Dylan McKay dada014781 [AVR] When lowering shifts into loops, put newly generated MBBs in the same
spot as the original MBB

Discovered in avr-rust/rust#62
https://github.com/avr-rust/rust/issues/62

Patch by Gergo Erdi.

llvm-svn: 314180
2017-09-26 00:51:03 +00:00
Jonas Paulsson 024e319489 [SystemZ, LoopStrengthReduce]
This patch makes LSR generate better code for SystemZ in the cases of memory
intrinsics, Load->Store pairs or comparison of immediate with memory.

In order to achieve this, the following common code changes were made:

 * New TTI hook: LSRWithInstrQueries(), which defaults to false. Controls if
 LSR should do instruction-based addressing evaluations by calling
 isLegalAddressingMode() with the Instruction pointers.
 * In LoopStrengthReduce: handle address operands of memset, memmove and memcpy
 as address uses, and call isFoldableMemAccessOffset() for any LSRUse::Address,
 not just loads or stores.

SystemZ changes:

 * isLSRCostLess() implemented with Insns first, and without ImmCost.
 * New function supportedAddressingMode() that is a helper for TTI methods
 looking at Instructions passed via pointers.

Review: Ulrich Weigand, Quentin Colombet
https://reviews.llvm.org/D35262
https://reviews.llvm.org/D35049

llvm-svn: 308729
2017-07-21 11:59:37 +00:00
Dylan McKay 043fa4b3d6 [AVR] Fix a big in shift operator lowering; Authored by Dr. Gergo Erdi
When generating code for a shift loop, check the shift
 amount against the literal value 0, not R0

llvm-svn: 304284
2017-05-31 06:27:46 +00:00
Dylan McKay 0c4debc123 [AVR] When lowering Select8/Select16, put newly generated MBBs in the same spot
Contributed by Dr. Gergő Érdi.

Fixes a bug.

Raised from (https://github.com/avr-rust/rust/issues/49).

llvm-svn: 302973
2017-05-13 00:22:34 +00:00
Leslie Zhai a1149e01d2 [AVR] Migrate to new StructType::get owing to Supress all uses of LLVM_END_WITH_NULL
Reviewers: dylanmckay, jroelofs, RKSimon, serge-sans-paille

Reviewed By: serge-sans-paille

Differential Revision: https://reviews.llvm.org/D33119

llvm-svn: 302885
2017-05-12 09:08:03 +00:00
Serge Pavlov d526b13e61 Add extra operand to CALLSEQ_START to keep frame part set up previously
Using arguments with attribute inalloca creates problems for verification
of machine representation. This attribute instructs the backend that the
argument is prepared in stack prior to  CALLSEQ_START..CALLSEQ_END
sequence (see http://llvm.org/docs/InAlloca.htm for details). Frame size
stored in CALLSEQ_START in this case does not count the size of this
argument. However CALLSEQ_END still keeps total frame size, as caller can
be responsible for cleanup of entire frame. So CALLSEQ_START and
CALLSEQ_END keep different frame size and the difference is treated by
MachineVerifier as stack error. Currently there is no way to distinguish
this case from actual errors.

This patch adds additional argument to CALLSEQ_START and its
target-specific counterparts to keep size of stack that is set up prior to
the call frame sequence. This argument allows MachineVerifier to calculate
actual frame size associated with frame setup instruction and correctly
process the case of inalloca arguments.

The changes made by the patch are:
- Frame setup instructions get the second mandatory argument. It
  affects all targets that use frame pseudo instructions and touched many
  files although the changes are uniform.
- Access to frame properties are implemented using special instructions
  rather than calls getOperand(N).getImm(). For X86 and ARM such
  replacement was made previously.
- Changes that reflect appearance of additional argument of frame setup
  instruction. These involve proper instruction initialization and
  methods that access instruction arguments.
- MachineVerifier retrieves frame size using method, which reports sum of
  frame parts initialized inside frame instruction pair and outside it.

The patch implements approach proposed by Quentin Colombet in
https://bugs.llvm.org/show_bug.cgi?id=27481#c1.
It fixes 9 tests failed with machine verifier enabled and listed
in PR27481.

Differential Revision: https://reviews.llvm.org/D32394

llvm-svn: 302527
2017-05-09 13:35:13 +00:00
Dylan McKay 59e7fe3da8 [AVR] Implement non-constant bit rotations
This lets us do bit rotations of variable amount.

llvm-svn: 301794
2017-05-01 09:48:55 +00:00
Meador Inge 5d3c599e82 [AVR] Fix build after r298178
r298178 capitalized the fields in `ArgListEntry`.  All the official
targets were updated accordingly, but as an experimental target AVR
was missed.

llvm-svn: 298677
2017-03-24 01:57:29 +00:00
Reid Kleckner b518054b87 Rename AttributeSet to AttributeList
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.

Rename AttributeSetImpl to AttributeListImpl to follow suit.

It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.

Reviewers: sanjoy, javed.absar, chandlerc, pete

Reviewed By: pete

Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits

Differential Revision: https://reviews.llvm.org/D31102

llvm-svn: 298393
2017-03-21 16:57:19 +00:00
Nirav Dave ac6081cb67 Make library calls sensitive to regparm module flag (Fixes PR3997).
Reviewers: mkuper, rnk

Subscribers: mehdi_amini, jyknight, aemerson, llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D27050

llvm-svn: 298179
2017-03-18 00:44:07 +00:00
Dylan McKay ccd819ad94 [AVR] Implement stacksave/stackrestore by expanding (PR31342)
Summary:
Authored by Florian Zeitz.

This implements the missing stacksave/stackrestore intrinsics via expansion.

Output of `llc -O0 -march=avr ~/devel/llvm/test/CodeGen/Generic/stacksave-restore.ll` for sanity checking (comments mine):

```
	.text
	.file	".../llvm/test/CodeGen/Generic/stacksave-restore.ll"
	.globl	test
	.p2align	1
	.type	test,@function
test:                                   ; @test
; BB#0:
	push	r28
	push	r29

	in	r28, 61
	in	r29, 62
	sbiw	r28, 4
	in	r0, 63
	cli
	out	62, r29
	out	63, r0
	out	61, r28

	in	r18, 61
	in	r19, 62

	mov	r20, r22
	mov	r21, r23

	in	r30, 61
	in	r31, 62

	lsl	r22
	rol	r23
	lsl	r22
	rol	r23
	in	r26, 61
	in	r27, 62
	sub	r26, r22
	sbc	r27, r23
	andi	r26, 252
	in	r0, 63
	cli
	out	62, r27
	out	63, r0
	out	61, r26

	in	r0, 63
	cli
	out	62, r31
	out	63, r0
	out	61, r30

	in	r30, 61
	in	r31, 62
	sub	r30, r22
	sbc	r31, r23
	andi	r30, 252
	in	r0, 63
	cli
	out	62, r31
	out	63, r0
	out	61, r30

	std	Y+3, r24                ; 2-byte Folded Spill
	std	Y+4, r25                ; 2-byte Folded Spill

	mov	r24, r26
	mov	r25, r27

	in	r0, 63
	cli
	out	62, r19
	out	63, r0
	out	61, r18

	std	Y+1, r20                ; 2-byte Folded Spill
	std	Y+2, r21                ; 2-byte Folded Spill

	adiw	r28, 4
	in	r0, 63
	cli
	out	62, r29
	out	63, r0
	out	61, r28

	pop	r29
	pop	r28
	ret
.Lfunc_end0:
	.size	test, .Lfunc_end0-test
```

Reviewers: dylanmckay

Reviewed By: dylanmckay

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29553

llvm-svn: 294146
2017-02-05 21:35:45 +00:00
Dylan McKay 7a3eb290ef [AVR] Support zero-sized arguments in defined methods
It is sufficient to skip emission of these arguments as we have nothing
to actually pass through the function call.

The AVR-GCC reference has nothing to say about zero-sized arguments,
presumably because C/C++ doesn't support them. This means we don't have
to worry about ABI differences.

llvm-svn: 294119
2017-02-05 09:53:45 +00:00
Dylan McKay 8fa6d8db9c [AVR] Implement TargetLoweing::getRegisterByName
This allows the use of the 'read_register' intrinsics used by clang's
named register globals features.

llvm-svn: 291375
2017-01-07 23:39:47 +00:00
Dylan McKay 99b756eb40 [AVR] Expand 'SELECT_CC' nodes whereever possible
llvm-svn: 288905
2016-12-07 12:34:47 +00:00
Dylan McKay 7549b0a013 [AVR] Add instruction selection lowering code
Summary: This adds AVRISelLowering.cpp

Reviewers: arsenm, kparzysz

Subscribers: llvm-commits, modocache, japaric, wdng, beanz, mgorny

Differential Revision: https://reviews.llvm.org/D25034

llvm-svn: 285790
2016-11-02 06:47:40 +00:00
Dylan McKay 7e91886a3f Revert "[AVR] Add instruction selection lowering code"
I accidentally comitted it.

llvm-svn: 282712
2016-09-29 12:49:18 +00:00
Dylan McKay b79c01a423 [AVR] Add instruction selection lowering code
Summary: This adds AVRISelLowering.cpp

Reviewers: kparzysz, arsenm

Subscribers: wdng, beanz, mgorny

Differential Revision: https://reviews.llvm.org/D25034

llvm-svn: 282711
2016-09-29 12:44:38 +00:00