Commit Graph

1243 Commits

Author SHA1 Message Date
Evan Cheng f8bad08001 Fix a long standing tail call optimization bug. When a libcall is emitted
legalizer always use the DAG entry node. This is wrong when the libcall is
emitted as a tail call since it effectively folds the return node. If
the return node's input chain is not the entry (i.e. call, load, or store)
use that as the tail call input chain.

PR12419
rdar://9770785
rdar://11195178

llvm-svn: 154370
2012-04-10 01:51:00 +00:00
Chad Rosier e0e38f61a5 When performing a truncating store, it's possible to rearrange the data
in-register, such that we can use a single vector store rather then a 
series of scalar stores.

For func_4_8 the generated code

	vldr	d16, LCPI0_0
	vmov	d17, r0, r1
	vadd.i16	d16, d17, d16
	vmov.u16	r0, d16[3]
	strb	r0, [r2, #3]
	vmov.u16	r0, d16[2]
	strb	r0, [r2, #2]
	vmov.u16	r0, d16[1]
	strb	r0, [r2, #1]
	vmov.u16	r0, d16[0]
	strb	r0, [r2]
	bx	lr

becomes

	vldr	d16, LCPI0_0
	vmov	d17, r0, r1
	vadd.i16	d16, d17, d16
	vuzp.8	d16, d17
	vst1.32	{d16[0]}, [r2, :32]
	bx	lr

I'm not fond of how this combine pessimizes 2012-03-13-DAGCombineBug.ll,
but I couldn't think of a way to judiciously apply this combine.

This

	ldrh	r0, [r0, #4]
	strh	r0, [r1]

becomes

	vldr	d16, [r0]
	vmov.u16	r0, d16[2]
	vmov.32	d16[0], r0
	vuzp.16	d16, d17
	vst1.32	{d16[0]}, [r1, :32]

PR11158
rdar://10703339

llvm-svn: 154340
2012-04-09 20:32:02 +00:00
Duncan Sands 5f8397a934 Convert floating point division by a constant into multiplication by the
reciprocal if converting to the reciprocal is exact.  Do it even if inexact
if -ffast-math.  This substantially speeds up ac.f90 from the polyhedron
benchmarks.

llvm-svn: 154265
2012-04-07 20:04:00 +00:00
Jakob Stoklund Olesen 967b86a0a2 Allow negative immediates in ARM and Thumb2 compares.
ARM and Thumb2 mode can use cmn instructions to compare against negative
immediates. Thumb1 mode can't.

llvm-svn: 154183
2012-04-06 17:45:04 +00:00
James Molloy 1ea6473688 An oversight when applying the patches for r150956 and r150957 to a vanilla tree meant I forgot to svn add these testcases.
Noticed while investigating PR12274!

llvm-svn: 154090
2012-04-05 10:01:12 +00:00
Jakob Stoklund Olesen f2390e8303 Pass the right sign to TLI->isLegalICmpImmediate.
LSR can fold three addressing modes into its ICmpZero node:

  ICmpZero BaseReg + Offset      => ICmp BaseReg, -Offset
  ICmpZero -1*ScaleReg + Offset  => ICmp ScaleReg, Offset
  ICmpZero BaseReg + -1*ScaleReg => ICmp BaseReg, ScaleReg

The first two cases are only used if TLI->isLegalICmpImmediate() likes
the offset.

Make sure the right Offset sign is passed to this method in the second
case. The ARM version is not symmetric.

<rdar://problem/11184260>

llvm-svn: 154079
2012-04-05 03:10:56 +00:00
Jakob Stoklund Olesen 0a5b72f0e4 Implement ARMBaseInstrInfo::commuteInstruction() for MOVCCr.
A MOVCCr instruction can be commuted by inverting the condition. This
can help reduce register pressure and remove unnecessary copies in some
cases.

<rdar://problem/11182914>

llvm-svn: 154033
2012-04-04 18:23:42 +00:00
Jakob Stoklund Olesen 291007b055 Allocate virtual registers in ascending order.
This is just the fallback tie-breaker ordering, the main allocation
order is still descending size.

Patch by Shamil Kurmangaleev!

llvm-svn: 153904
2012-04-02 22:30:39 +00:00
Lang Hames aaafacd07e During two-address lowering, rescheduling an instruction does not untie
operands. Make TryInstructionTransform return false to reflect this.
Fixes PR11861.

llvm-svn: 153892
2012-04-02 19:58:43 +00:00
Nadav Rotem b078350872 This commit contains a few changes that had to go in together.
1. Simplify xor/and/or (bitcast(A), bitcast(B)) -> bitcast(op (A,B))
   (and also scalar_to_vector).

2. Xor/and/or are indifferent to the swizzle operation (shuffle of one src).
   Simplify xor/and/or (shuff(A), shuff(B)) -> shuff(op (A, B))

3. Optimize swizzles of shuffles:  shuff(shuff(x, y), undef) -> shuff(x, y).

4. Fix an X86ISelLowering optimization which was very bitcast-sensitive.

Code which was previously compiled to this:

movd    (%rsi), %xmm0
movdqa  .LCPI0_0(%rip), %xmm2
pshufb  %xmm2, %xmm0
movd    (%rdi), %xmm1
pshufb  %xmm2, %xmm1
pxor    %xmm0, %xmm1
pshufb  .LCPI0_1(%rip), %xmm1
movd    %xmm1, (%rdi)
ret

Now compiles to this:

movl    (%rsi), %eax
xorl    %eax, (%rdi)
ret

llvm-svn: 153848
2012-04-01 19:31:22 +00:00
Evan Cheng a40d40602c ARM target should allow codegenprep to duplicate ret instructions to enable tailcall opt. rdar://11140249
llvm-svn: 153717
2012-03-30 01:24:39 +00:00
Lang Hames 323a5ced21 Change the constant in this testcase so that it results in a constant pool
load.

llvm-svn: 153704
2012-03-29 23:52:38 +00:00
Evan Cheng a2b48d985b ARM has a peephole optimization which looks for a def / use pair. The def
produces a 32-bit immediate which is consumed by the use. It tries to 
fold the immediate by breaking it into two parts and fold them into the
immmediate fields of two uses. e.g
       movw    r2, #40885
       movt    r3, #46540
       add     r0, r0, r3
=>
       add.w   r0, r0, #3019898880
       add.w   r0, r0, #30146560
;
However, this transformation is incorrect if the user produces a flag. e.g.
       movw    r2, #40885
       movt    r3, #46540
       adds    r0, r0, r3
=>
       add.w   r0, r0, #3019898880
       adds.w  r0, r0, #30146560
Note the adds.w may not set the carry flag even if the original sequence
would.

rdar://11116189

llvm-svn: 153484
2012-03-26 23:31:00 +00:00
Eli Bendersky f33086052d Continue cleanup of LIT, getting rid of the remaining artifacts from dejagnu
* Removed test/lib/llvm.exp - it is no longer needed 
* Deleted the dg.exp reading code from test/lit.cfg. There are no dg.exp files
  left in the test suite so this code is no longer required. test/lit.cfg is
  now much shorter and clearer 
* Removed a lot of duplicate code in lit.local.cfg files that need access to
  the root configuration, by adding a "root" attribute to the TestingConfig
  object. This attribute is dynamically computed to provide the same
  information as was previously provided by the custom getRoot functions. 
* Documented the config.root attribute in docs/CommandGuide/lit.pod

llvm-svn: 153408
2012-03-25 09:02:19 +00:00
Andrew Trick d97b83e320 Remove -enable-lsr-nested in time for 3.1.
Tests cases have been removed but attached to open PR12330.

llvm-svn: 153286
2012-03-22 22:42:45 +00:00
Chad Rosier 6a63a74113 [fast-isel] Fold "urem x, pow2" -> "and x, pow2-1". This should fix the 271%
execution-time regression for nsieve-bits on the ARMv7 -O0 -g nightly tester.
This may also improve compile-time on architectures that would otherwise 
generate a libcall for urem (e.g., ARM) or fall back to the DAG selector.
rdar://10810716

llvm-svn: 153230
2012-03-22 00:21:17 +00:00
Chad Rosier cbf45a6d8a Fix test case from r153135.
llvm-svn: 153140
2012-03-20 21:49:54 +00:00
Anton Korobeynikov 3edd854d64 Perform mul combine when multiplying wiht negative constants.
Patch by Weiming Zhao!
This fixes PR12212

llvm-svn: 153049
2012-03-19 19:19:50 +00:00
Chad Rosier 26d05887d9 [fast-isel] Address Eli's comments for r152847. Specifically, add a test case
and still allow immediate encoding, just not with cmn.
rdar://11038907

llvm-svn: 152869
2012-03-15 22:54:20 +00:00
Jim Grosbach d28888dd77 ARM case-insensitive checking for APSR_nzcv.
rdar://11056591

llvm-svn: 152846
2012-03-15 21:34:14 +00:00
Lang Hames c35ee8b54a Use vmov.f32 to materialize f32 consts on ARM. This relaxes constraints on
register allocation by allowing all 32 D-registers to be used. Patch by Cameron
Zwarich.

llvm-svn: 152824
2012-03-15 18:49:02 +00:00
Evan Cheng 7bf83096df DAG combine incorrectly optimize (i32 vextract (v4i16 load $addr), c) to
(i16 load $addr+c*sizeof(i16)) and replace uses of (i32 vextract) with the
i16 load. It should issue an extload instead: (i32 extload $addr+c*sizeof(i16)).

rdar://11035895

llvm-svn: 152675
2012-03-13 22:00:52 +00:00
Evan Cheng 80893ce5f5 Extend r148086 to check for [r +/- reg] address mode. This fixes queens performance regression (due to increased register pressure from overly aggressive pre-inc formation).
llvm-svn: 152162
2012-03-06 23:33:32 +00:00
Jakob Stoklund Olesen d9b427ee65 Add <imp-def> operands when reloading into physregs.
When an instruction only writes sub-registers, it is still necessary to
add an <imp-def> operand for the super-register.  When reloading into a
virtual register, rewriting will add the operand, but when loading
directly into a virtual register, the <imp-def> operand is still
necessary.

llvm-svn: 152095
2012-03-06 02:48:17 +00:00
Lang Hames 718cfbe05a Split fpscr into two registers: FPSCR and FPSCR_NZCV.
The fpscr register contains both flags (set by FP operations/comparisons) and
control bits. The control bits (FPSCR) should be reserved, since they're always
available and needn't be defined before use. The flag bits (FPSCR_NZCV) should
like to be unreserved so they can be hoisted by MachineCSE. This fixes PR12165.

llvm-svn: 152076
2012-03-06 00:19:55 +00:00
Sebastian Pop 957a6583f1 updated patch for the ARM fused multiply add/sub
In this update:
- I assumed neon2 does not imply vfpv4, but neon and vfpv4 imply neon2.
- I kept setting .fpu=neon-vfpv4 code attribute because that is what the
assembler understands.

Patch by Ana Pazos <apazos@codeaurora.org>

llvm-svn: 152036
2012-03-05 17:39:52 +00:00
Jakob Stoklund Olesen f729ceae04 Use <def,undef> operands when spilling NEON bundles.
MachineOperands that define part of a virtual register must have an
<undef> flag if they are not intended as read-modify-write operands.

The old trick of adding an <imp-def> operand doesn't work any longer.

Fixes PR12177.

llvm-svn: 152008
2012-03-04 18:40:30 +00:00
Bill Wendling 97b9359623 Do trivial CSE of dead BBs during codegen preparation.
Some BBs can become dead after codegen preparation. If we delete them here, it
could help enable tail-call optimizations later on.
<rdar://problem/10256573>

llvm-svn: 152002
2012-03-04 10:46:01 +00:00
Jakob Stoklund Olesen a0bd36e3bc Fix RA-dependent test.
llvm-svn: 151958
2012-03-03 00:26:30 +00:00
Evan Cheng d12af5dc69 Neuter the optimization I implemented with r107852 and r108258 which turn some
floating point equality comparisons into integer ones with -ffast-math. The
issue is the optimization causes +0.0 != -0.0.

Now the optimization is only done when one side is known to be 0.0. The other
side's sign bit is masked off for the comparison.

rdar://10964603

llvm-svn: 151861
2012-03-01 23:27:13 +00:00
Chad Rosier 2913f500fa Revert r151816 as Jim has the appropriate fix.
llvm-svn: 151818
2012-03-01 17:41:19 +00:00
Chad Rosier f0208ed76a Fix testcases from r151807.
llvm-svn: 151816
2012-03-01 17:31:30 +00:00
Jim Grosbach 394ad59d90 Add missing triple for tests.
Make darwin bots happier.

llvm-svn: 151813
2012-03-01 17:30:32 +00:00
James Molloy f6298e9281 Fix a codegen fault in which log2 or exp2 could be dead-code eliminated even though they could have sideeffects.
Only allow log2/exp2 to be converted to an intrinsic if they are declared "readnone".

llvm-svn: 151807
2012-03-01 14:32:18 +00:00
Daniel Dunbar ee7b899343 Revert r151623 "Some ARM implementaions, e.g. A-series, does return stack prediction. ...", it is breaking the Clang build during the Compiler-RT part.
llvm-svn: 151630
2012-02-28 15:36:07 +00:00
Evan Cheng 87c7b09d8d Some ARM implementaions, e.g. A-series, does return stack prediction. That is,
the processor keeps a return addresses stack (RAS) which stores the address
and the instruction execution state of the instruction after a function-call
type branch instruction.

Calling a "noreturn" function with normal call instructions (e.g. bl) can
corrupt RAS and causes 100% return misprediction so LLVM should use a
unconditional branch instead. i.e.
mov lr, pc
b _foo
The "mov lr, pc" is issued in order to get proper backtrace.

rdar://8979299

llvm-svn: 151623
2012-02-28 06:42:03 +00:00
Jakob Stoklund Olesen 4c5ad2b812 Handle regmasks in MachineCSE.
Don't attempt to extend physreg live ranges across calls.

<rdar://problem/10942095>

llvm-svn: 151610
2012-02-28 02:08:50 +00:00
Kristof Beyls b59291a8e6 test commit. removing unnecessary whitespace.
llvm-svn: 151363
2012-02-24 13:52:45 +00:00
Jim Grosbach c01104dfbf Thumb2 size reduction fix for tied operands of tMUL.
The tied source operand of tMUL is the second source operand, not the
first like every other two-address thumb instruction. Special case it
in the size reduction pass to make sure we create the tMUL instruction
properly.

llvm-svn: 151315
2012-02-24 00:33:36 +00:00
Dan Gohman d4a77c4682 When emitting a cmp with 0 for a lowered select, mask out the high
bits of the value carying the boolean condition, as their contents
are undefined. This fixes rdar://10887484.

llvm-svn: 151310
2012-02-24 00:09:36 +00:00
Jakob Stoklund Olesen aae960d978 Make tests less sensitive to scheduling changes.
llvm-svn: 151260
2012-02-23 17:19:34 +00:00
Anton Korobeynikov a22828e085 Fix to make sure that a comdat group gets generated correctly for a static member
of instantiated C++ templates.

Patch by Kristof Beyls!

llvm-svn: 151250
2012-02-23 10:36:04 +00:00
Evan Cheng f258a15bdf Canonicalize (srl (bswap x), 16) to (rotr (bswap x), 16) if the high 16 bits
of x are zero. This optimizes rev + lsr 16 to rev16.

rdar://10750814

llvm-svn: 151230
2012-02-23 02:58:19 +00:00
Evan Cheng e87681cf34 Optimize a couple of common patterns involving conditional moves where the false
value is zero. Instead of a cmov + op, issue an conditional op instead. e.g.
    cmp   r9, r4
    mov   r4, #0
    moveq r4, #1 
    orr   lr, lr, r4

should be:
    cmp   r9, r4
    orreq lr, lr, #1

That is, optimize (or x, (cmov 0, y, cond)) to (or.cond x, y). Similarly extend
this to xor as well as (and x, (cmov -1, y, cond)) => (and.cond x, y).

It's possible to extend this to ADD and SUB but I don't think they are common.

rdar://8659097

llvm-svn: 151224
2012-02-23 01:19:06 +00:00
Evan Cheng 0460ae8d80 Proper support for a bastardized darwin-eabi hybird ABI.
llvm-svn: 151083
2012-02-21 20:46:00 +00:00
Chad Rosier fcd29ae390 [fast-isel] Add support for returning non-legal types with no sign- or zero-
entend flag.

llvm-svn: 150774
2012-02-17 01:21:28 +00:00
Eli Bendersky 924f9a671d Replace all instances of dg.exp file with lit.local.cfg, since all tests are run with LIT now and now Dejagnu. dg.exp is no longer needed.
Patch reviewed by Daniel Dunbar. It will be followed by additional cleanup patches.

llvm-svn: 150664
2012-02-16 06:28:33 +00:00
Lang Hames 595111f221 Tighten physical register invariants: Allocatable physical registers can
only be live in to a block if it is the function entry point or a landing pad.

llvm-svn: 150494
2012-02-14 18:51:53 +00:00
Andrew Trick d3f8fe81f4 RegAlloc superpass: includes phi elimination, coalescing, and scheduling.
Creates a configurable regalloc pipeline.

Ensure specific llc options do what they say and nothing more: -reglloc=... has no effect other than selecting the allocator pass itself. This patch introduces a new umbrella flag, "-optimize-regalloc", to enable/disable the optimizing regalloc "superpass". This allows for example testing coalscing and scheduling under -O0 or vice-versa.

When a CodeGen pass requires the MachineFunction to have a particular property, we need to explicitly define that property so it can be directly queried rather than naming a specific Pass. For example, to check for SSA, use MRI->isSSA, not addRequired<PHIElimination>.

CodeGen transformation passes are never "required" as an analysis

ProcessImplicitDefs does not require LiveVariables.

We have a plan to massively simplify some of the early passes within the regalloc superpass.

llvm-svn: 150226
2012-02-10 04:10:36 +00:00
Chad Rosier 0ee8c513f7 [fast-isel] Add support for SUBs with non-legal types.
llvm-svn: 150047
2012-02-08 02:45:44 +00:00