Commit Graph

584 Commits

Author SHA1 Message Date
Diana Picus 68be1eb885 Revert "CodeGen: If Convert blocks that would form a diamond when tail-merged."
This reverts commit r278287.

This commit broke the clang-cmake-thumbv7-a15-full-sh bot.
See https://llvm.org/bugs/show_bug.cgi?id=28949

llvm-svn: 278621
2016-08-14 02:10:18 +00:00
Kyle Butt e1c931b171 CodeGen: If Convert blocks that would form a diamond when tail-merged.
The following function currently relies on tail-merging for if
conversion to succeed. The common tail of cond_true and cond_false is
extracted, and this then forms a diamond pattern that can be
successfully if converted.

If this block does not get extracted, either because tail-merging is
disabled or the threshold is higher, we should still recognize this
pattern and if-convert it.

Fixed a regression in the original commit. Need to un-reverse branches after
reversing them, or other conversions go awry.

define i32 @t2(i32 %a, i32 %b) nounwind {
entry:
        %tmp1434 = icmp eq i32 %a, %b           ; <i1> [#uses=1]
        br i1 %tmp1434, label %bb17, label %bb.outer

bb.outer:               ; preds = %cond_false, %entry
        %b_addr.021.0.ph = phi i32 [ %b, %entry ], [ %tmp10, %cond_false ]
        %a_addr.026.0.ph = phi i32 [ %a, %entry ], [ %a_addr.026.0, %cond_false ]
        br label %bb

bb:             ; preds = %cond_true, %bb.outer
        %indvar = phi i32 [ 0, %bb.outer ], [ %indvar.next, %cond_true ]
        %tmp. = sub i32 0, %b_addr.021.0.ph
        %tmp.40 = mul i32 %indvar, %tmp.
        %a_addr.026.0 = add i32 %tmp.40, %a_addr.026.0.ph
        %tmp3 = icmp sgt i32 %a_addr.026.0, %b_addr.021.0.ph
        br i1 %tmp3, label %cond_true, label %cond_false

cond_true:              ; preds = %bb
        %tmp7 = sub i32 %a_addr.026.0, %b_addr.021.0.ph
        %tmp1437 = icmp eq i32 %tmp7, %b_addr.021.0.ph
        %indvar.next = add i32 %indvar, 1
        br i1 %tmp1437, label %bb17, label %bb

cond_false:             ; preds = %bb
        %tmp10 = sub i32 %b_addr.021.0.ph, %a_addr.026.0
        %tmp14 = icmp eq i32 %a_addr.026.0, %tmp10
        br i1 %tmp14, label %bb17, label %bb.outer

bb17:           ; preds = %cond_false, %cond_true, %entry
        %a_addr.026.1 = phi i32 [ %a, %entry ], [ %tmp7, %cond_true ], [ %a_addr.026.0, %cond_false ]
        ret i32 %a_addr.026.1
}

Without tail-merging or diamond-tail if conversion:
LBB1_1:                                 @ %bb
                                        @ =>This Inner Loop Header: Depth=1
        cmp     r0, r1
        ble     LBB1_3
@ BB#2:                                 @ %cond_true
                                        @   in Loop: Header=BB1_1 Depth=1
        subs    r0, r0, r1
        cmp     r1, r0
        it      ne
        cmpne   r0, r1
        bgt     LBB1_4
LBB1_3:                                 @ %cond_false
                                        @   in Loop: Header=BB1_1 Depth=1
        subs    r1, r1, r0
        cmp     r1, r0
        bne     LBB1_1
LBB1_4:                                 @ %bb17
        bx      lr

With diamond-tail if conversion, but without tail-merging:
@ BB#0:                                 @ %entry
        cmp     r0, r1
        it      eq
        bxeq    lr
LBB1_1:                                 @ %bb
                                        @ =>This Inner Loop Header: Depth=1
        cmp     r0, r1
        ite     le
        suble   r1, r1, r0
        subgt   r0, r0, r1
        cmp     r1, r0
        bne     LBB1_1
@ BB#2:                                 @ %bb17
        bx      lr

llvm-svn: 278287
2016-08-10 20:45:56 +00:00
Sam Parker 62965c96df [ARM] Improve sxta{b|h} and uxta{b|h} tests
Created a Thumb2 predicated pattern matcher that uses Thumb2 and
HasT2ExtractPack and used it to redefine the patterns for sxta{b|h}
and uxta{b|h}. Also used the similar patterns to fill in isel pattern
gaps for the corresponding instructions in the ARM backend.
The patch is mainly changes to tests since most of this functionality
appears not to have been tested.

Differential Revision: https://reviews.llvm.org/D23273

llvm-svn: 278207
2016-08-10 09:34:34 +00:00
Nico Weber 99ceee8a85 Revert r277905, it caused PR28894
llvm-svn: 277962
2016-08-07 20:18:04 +00:00
Kyle Butt 71cb44d969 CodeGen: If Convert blocks that would form a diamond when tail-merged.
The following function currently relies on tail-merging for if
conversion to succeed. The common tail of cond_true and cond_false is
extracted, and this then forms a diamond pattern that can be
successfully if converted.

If this block does not get extracted, either because tail-merging is
disabled or the threshold is higher, we should still recognize this
pattern and if-convert it.
define i32 @t2(i32 %a, i32 %b) nounwind {
entry:
	%tmp1434 = icmp eq i32 %a, %b		; <i1> [#uses=1]
	br i1 %tmp1434, label %bb17, label %bb.outer

bb.outer:		; preds = %cond_false, %entry
	%b_addr.021.0.ph = phi i32 [ %b, %entry ], [ %tmp10, %cond_false ]
	%a_addr.026.0.ph = phi i32 [ %a, %entry ], [ %a_addr.026.0, %cond_false ]
	br label %bb

bb:		; preds = %cond_true, %bb.outer
	%indvar = phi i32 [ 0, %bb.outer ], [ %indvar.next, %cond_true ]
	%tmp. = sub i32 0, %b_addr.021.0.ph
	%tmp.40 = mul i32 %indvar, %tmp.
	%a_addr.026.0 = add i32 %tmp.40, %a_addr.026.0.ph
	%tmp3 = icmp sgt i32 %a_addr.026.0, %b_addr.021.0.ph
	br i1 %tmp3, label %cond_true, label %cond_false

cond_true:		; preds = %bb
	%tmp7 = sub i32 %a_addr.026.0, %b_addr.021.0.ph
	%tmp1437 = icmp eq i32 %tmp7, %b_addr.021.0.ph
	%indvar.next = add i32 %indvar, 1
	br i1 %tmp1437, label %bb17, label %bb

cond_false:		; preds = %bb
	%tmp10 = sub i32 %b_addr.021.0.ph, %a_addr.026.0
	%tmp14 = icmp eq i32 %a_addr.026.0, %tmp10
	br i1 %tmp14, label %bb17, label %bb.outer

bb17:		; preds = %cond_false, %cond_true, %entry
	%a_addr.026.1 = phi i32 [ %a, %entry ], [ %tmp7, %cond_true ], [ %a_addr.026.0, %cond_false ]
	ret i32 %a_addr.026.1
}

Without tail-merging or diamond-tail if conversion:
LBB1_1:                                 @ %bb
                                        @ =>This Inner Loop Header: Depth=1
        cmp     r0, r1
        ble     LBB1_3
@ BB#2:                                 @ %cond_true
                                        @   in Loop: Header=BB1_1 Depth=1
        subs    r0, r0, r1
        cmp     r1, r0
        it      ne
        cmpne   r0, r1
        bgt     LBB1_4
LBB1_3:                                 @ %cond_false
                                        @   in Loop: Header=BB1_1 Depth=1
        subs    r1, r1, r0
        cmp     r1, r0
        bne     LBB1_1
LBB1_4:                                 @ %bb17
        bx      lr

With diamond-tail if conversion, but without tail-merging:
@ BB#0:                                 @ %entry
        cmp     r0, r1
        it      eq
        bxeq    lr
LBB1_1:                                 @ %bb
                                        @ =>This Inner Loop Header: Depth=1
        cmp     r0, r1
        ite     le
        suble   r1, r1, r0
        subgt   r0, r0, r1
        cmp     r1, r0
        bne     LBB1_1
@ BB#2:                                 @ %bb17
        bx      lr

llvm-svn: 277905
2016-08-06 01:52:37 +00:00
James Molloy ae5ff990ae [Thumb] Reapply r272251 with a fix for PR28348 (mk 2)
The important thing I was missing was ensuring newly added constants were kept in topological order. Repositioning the node is correct if the constant is newly added (so it has no topological ordering) but wrong if it already existed - positioning it next in the worklist would break the topological ordering.

Original commit message:
  [Thumb] Select a BIC instead of AND if the immediate can be encoded more optimally negated

  If an immediate is only used in an AND node, it is possible that the immediate can be more optimally materialized when negated. If this is the case, we can negate the immediate and use a BIC instead;

    int i(int a) {
      return a & 0xfffffeec;
    }

  Used to produce:
      ldr r1, [CONSTPOOL]
      ands r0, r1
    CONSTPOOL: 0xfffffeec

  And now produces:
      movs    r1, #255
      adds    r1, #20  ; Less costly immediate generation
      bics    r0, r1

llvm-svn: 274543
2016-07-05 12:37:13 +00:00
James Molloy c3b4ed4a70 Revert "[Thumb] Reapply r272251 with a fix for PR28348"
This reverts commit r274510 - it made green dragon unhappy.

llvm-svn: 274512
2016-07-04 17:14:24 +00:00
James Molloy 9f019835ef [Thumb] Reapply r272251 with a fix for PR28348
We were using DAG->getConstant instead of DAG->getTargetConstant. This meant that we could inadvertently increase the use count of a constant if stars aligned, which it did in this testcase. Increasing the use count of the constant could cause ISel to fall over (because DAGToDAG lowering assumed the constant had only one use!)

Original commit message:
  [Thumb] Select a BIC instead of AND if the immediate can be encoded more optimally negated

  If an immediate is only used in an AND node, it is possible that the immediate can be more optimally materialized when negated. If this is the case, we can negate the immediate and use a BIC instead;

    int i(int a) {
      return a & 0xfffffeec;
    }

  Used to produce:
      ldr r1, [CONSTPOOL]
      ands r0, r1
    CONSTPOOL: 0xfffffeec

  And now produces:
      movs    r1, #255
      adds    r1, #20  ; Less costly immediate generation
      bics    r0, r1

llvm-svn: 274510
2016-07-04 16:35:41 +00:00
Kyle Butt 267164df0a Codegen: Fix broken assumption in Tail Merge.
Tail merge was making the assumption that a layout successor or
predecessor was always a cfg successor/predecessor. Remove that
assumption. Changes to tests are necessary because the errant cfg edges
were preventing optimizations.

llvm-svn: 273700
2016-06-24 18:16:36 +00:00
Artur Pilipenko 4fec7b7131 Fix an old memset signature in 2009-09-01-PostRAProlog.ll test causing a buildbot failure
llvm-svn: 273573
2016-06-23 16:07:10 +00:00
Rafael Espindola afade35003 Don't print (PLT) on arm.
The R_ARM_PLT32 relocation is deprecated and is not produced by MC.

This means that the code being deleted is dead from the .o point of
view and was making the .s more confusing.

llvm-svn: 272909
2016-06-16 16:09:53 +00:00
Tim Northover b5ece527a1 ARM: stop emitting blx instructions for most calls on MachO.
I'm really not sure why we were in the first place, it's the linker's job to
convert between BL/BLX as necessary. Even worse, using BLX left Thumb calls
that could be locally resolved completely unencodable since all offsets to BLX
are multiples of 4.

rdar://26182344

llvm-svn: 269101
2016-05-10 19:17:47 +00:00
Mandeep Singh Grang e5a2f116d6 Fix PR26655: Bail out if all regs of an inst BUNDLE have the correct kill flag
Summary:
While setting kill flags on instructions inside a BUNDLE, we bail out as soon
as we set kill flag on a register.  But we are missing a check when all the
registers already have the correct kill flag set. We need to bail out in that
case as well.

This patch refactors the old code and simply makes use of the addRegisterKilled
function in MachineInstr.cpp in order to determine whether to set/remove kill
on an instruction.

Reviewers: apazos, t.p.northover, pete, MatzeB

Subscribers: MatzeB, davide, llvm-commits

Differential Revision: http://reviews.llvm.org/D17356

llvm-svn: 269092
2016-05-10 17:57:27 +00:00
Tim Northover a6dea06fe3 ARM: use r7 as the frame-pointer on all MachO targets.
This is better for a few reasons:
  + It matches the other tooling for iOS.
  + It matches EABI in more cases (i.e. Thumb-mode, and in practice we don't
    use ARM mode).
  + It leads to infinitesimally smaller code (0.2%, yay!).

rdar://25369506

llvm-svn: 266003
2016-04-11 22:27:40 +00:00
Kyle Butt 5e241b11ed [Codegen] Decrease minimum jump table density.
Minimum density for both optsize and non optsize are now options
-sparse-jump-table-density (default 10) for non optsize functions
-dense-jump-table-density (default 40) for optsize functions, which
matches the current default. This improves several benchmarks at google
at the cost of a small codesize increase. For code compiled with -Os,
the old behavior continues

llvm-svn: 264689
2016-03-29 00:23:41 +00:00
Matthias Braun f290912d22 ARM: Introduce conservative load/store optimization mode
Most of the time ARM has the CCR.UNALIGN_TRP bit set to false which
means that unaligned loads/stores do not trap and even extensive testing
will not catch these bugs. However the multi/double variants are not
affected by this bit and will still trap. In effect a more aggressive
load/store optimization will break existing (bad) code.

These bugs do not necessarily manifest in the broken code where the
misaligned pointer is formed but often later in perfectly legal code
where it is accessed. This means recompiling system libraries (which
have no alignment bugs) with a newer compiler will break existing
applications (with alignment bugs) that worked before.

So (under protest) I implemented this safe mode which limits the
formation of multi/double operations to cases that are not affected by
user code (stack operations like spills/reloads) or cases where the
normal operations trap anyway (floating point load/stores). It is
disabled by default.

Differential Revision: http://reviews.llvm.org/D17015

llvm-svn: 262504
2016-03-02 19:20:00 +00:00
Wei Mi a49559befb [SCEV] Try to reuse existing value during SCEV expansion
Current SCEV expansion will expand SCEV as a sequence of operations
and doesn't utilize the value already existed. This will introduce
redundent computation which may not be cleaned up throughly by
following optimizations.

This patch introduces an ExprValueMap which is a map from SCEV to the
set of equal values with the same SCEV. When a SCEV is expanded, the
set of values is checked and reused whenever possible before generating
a sequence of operations.

The original commit triggered regressions in Polly tests. The regressions
exposed two problems which have been fixed in current version.

1. Polly will generate a new function based on the old one. To generate an
instruction for the new function, it builds SCEV for the old instruction,
applies some tranformation on the SCEV generated, then expands the transformed
SCEV and insert the expanded value into new function. Because SCEV expansion
may reuse value cached in ExprValueMap, the value in old function may be
inserted into new function, which is wrong.
   In SCEVExpander::expand, there is a logic to check the cached value to
be used should dominate the insertion point. However, for the above
case, the check always passes. That is because the insertion point is
in a new function, which is unreachable from the old function. However
for unreachable node, DominatorTreeBase::dominates thinks it will be
dominated by any other node.
   The fix is to simply add a check that the cached value to be used in
expansion should be in the same function as the insertion point instruction.

2. When the SCEV is of scConstant type, expanding it directly is cheaper than
reusing a normal value cached. Although in the cached value set in ExprValueMap,
there is a Constant type value, but it is not easy to find it out -- the cached
Value set is not sorted according to the potential cost. Existing reuse logic
in SCEVExpander::expand simply chooses the first legal element from the cached
value set.
   The fix is that when the SCEV is of scConstant type, don't try the reuse
logic. simply expand it.

Differential Revision: http://reviews.llvm.org/D12090

llvm-svn: 259736
2016-02-04 01:27:38 +00:00
Wei Mi 97de385868 Revert r259662, which caused regressions on polly tests.
llvm-svn: 259675
2016-02-03 18:05:57 +00:00
Wei Mi ed133978a0 [SCEV] Try to reuse existing value during SCEV expansion
Current SCEV expansion will expand SCEV as a sequence of operations
and doesn't utilize the value already existed. This will introduce
redundent computation which may not be cleaned up throughly by
following optimizations.

This patch introduces an ExprValueMap which is a map from SCEV to the
set of equal values with the same SCEV. When a SCEV is expanded, the
set of values is checked and reused whenever possible before generating
a sequence of operations.

Differential Revision: http://reviews.llvm.org/D12090

llvm-svn: 259662
2016-02-03 17:05:12 +00:00
David Majnemer bff6b581e2 Address buildbot fallout from r259065
llvm-svn: 259074
2016-01-28 18:59:04 +00:00
Dan Gohman 61d15ae4f5 [MC] Use .p2align instead of .align
For historic reasons, the behavior of .align differs between targets.
Fortunately, there are alternatives, .p2align and .balign, which make the
interpretation of the parameter explicit, and which behave consistently across
targets.

This patch teaches MC to use .p2align instead of .align, so that people reading
code for multiple architectures don't have to remember which way each platform
does its .align directive.

Differential Revision: http://reviews.llvm.org/D16549

llvm-svn: 258750
2016-01-26 00:03:25 +00:00
Bill Seurer aea3d38d81 Fix test case label check
Several (but not all) of the labels that are checked for in this test case
are checked as strings instead of labels.  This can cause an apparent test
case failure if they are tested in an appropriately named directory.

For example, one of them that fails:

define zeroext i32 @test2(i32 %A.u, i32 %B.u)  {
; A8: test2
; A8: uxtab  r0, r0, r1


Output that causes it to fail:

. . .
	.file	"/home/seurer/llvm/llvm-test2/test/CodeGen/Thumb2/thumb2-uxt_rot.ll"
. . .
	.globl	test2
	.align	1
	.type	test2,%function
	.code	16                      @ @test2
	.thumb_func
test2:
	.fnstart


The "A8: test2" matches on the directory name instead of the label.

llvm-svn: 253702
2015-11-20 20:24:49 +00:00
Pete Cooper 67cf9a723b Revert "Change memcpy/memset/memmove to have dest and source alignments."
This reverts commit r253511.

This likely broke the bots in
http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/20202
http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/3787

llvm-svn: 253543
2015-11-19 05:56:52 +00:00
Pete Cooper 72bc23ef02 Change memcpy/memset/memmove to have dest and source alignments.
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

These intrinsics currently have an explicit alignment argument which is
required to be a constant integer.  It represents the alignment of the
source and dest, and so must be the minimum of those.

This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments.  The alignment
argument itself is removed.

There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe.  For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.

For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)

For out of tree owners, I was able to strip alignment from calls using sed by replacing:
  (call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
  $1i1 false)

and similarly for memmove and memcpy.

I then added back in alignment to test cases which needed it.

A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.

In IRBuilder itself, a new argument was added.  Instead of calling:
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)

There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool.  This is to prevent isVolatile here from passing its default
parameter to the source alignment.

Note, changes in future can now be made to codegen.  I didn't change anything here, but this
change should enable better memcpy code sequences.

Reviewed by Hal Finkel.

llvm-svn: 253511
2015-11-18 22:17:24 +00:00
Quentin Colombet 8cb95b8e51 [ARM] Enable shrink-wrapping by default.
Differential Revision: http://reviews.llvm.org/D14357

rdar://problem/21942589

llvm-svn: 253411
2015-11-18 00:40:54 +00:00
Renato Golin 93064025bd Revert "[ARM] Enable shrink-wrapping by default."
This reverts commit r252825, as it broke ASAN on ARM. Investigating...

llvm-svn: 252889
2015-11-12 13:34:50 +00:00
Matthias Braun b9610a6bc2 LegalizeDAG: Fix and improve FCOPYSIGN/FABS legalization
- Factor out code to query and modify the sign bit of a floatingpoint
  value as an integer. This also works if none of the targets integer
  types is big enough to hold all bits of the floatingpoint value.

- Legalize FABS(x) as FCOPYSIGN(x, 0.0) if FCOPYSIGN is available,
  otherwise perform bit manipulation on the sign bit. The previous code
  used "x >u 0 ? x : -x" which is incorrect for x being -0.0! It also
  takes 34 instructions on ARM Cortex-M4. With this patch we only
  require 5:
    vldr d0, LCPI0_0
    vmov r2, r3, d0
    lsrs r2, r3, #31
    bfi r1, r2, #31, #1
    bx lr
  (This could be further improved if the compiler would recognize that
   r2, r3 is zero).

- Only lower FCOPYSIGN(x, y) = sign(x) ? -FABS(x) : FABS(x) if FABS is
  available otherwise perform bit manipulation on the sign bit.

- Perform the sign(x) test by masking out the sign bit and comparing
  with 0 rather than shifting the sign bit to the highest position and
  testing for "<s 0". For x86 copysignl (on 80bit values) this gets us:
    testl $32768, %eax
  rather than:
    shlq $48, %rax
    sets %al
    testb %al, %al

Differential Revision: http://reviews.llvm.org/D11172

llvm-svn: 252839
2015-11-12 01:02:47 +00:00
Quentin Colombet 10f9813528 [ARM] Enable shrink-wrapping by default.
Differential Revision: http://reviews.llvm.org/D14357

rdar://problem/21942589

llvm-svn: 252825
2015-11-11 23:31:46 +00:00
Akira Hatanaka 3bfc3e2d2a [ARM] Handle t2ADDri in ARMAsmPrinter::EmitUnwindingInstruction.
This fixes a bug in ARMAsmPrinter::EmitUnwindingInstruction where
llvm_unreachable was reached because t2ADDri wasn't handled.

Test case provided by Tim Northover.

rdar://problem/23270609

http://reviews.llvm.org/D14518

llvm-svn: 252557
2015-11-10 00:10:41 +00:00
Artyom Skrobov 5a6e39454e [ARM] Renaming +t2dsp feature into +dsp, as discussed on llvm-dev
llvm-svn: 251125
2015-10-23 17:19:19 +00:00
Oliver Stannard d3d114ba54 [ARM] Use correct half-precision functions in EABI mode
The ARM RTABI defines the half- to single-precision float conversion functions
with an __aeabi prefix, but libgcc only has them with a __gnu prefix. Therefore
we need to emit the __aeabi version when compiling with an eabi or eabihf
triple, and the __gnu version with a gnueabi or gnueabihf triple.

llvm-svn: 249565
2015-10-07 16:58:49 +00:00
Jeroen Ketema ab99b59e8c [ARM][NEON] Use address space in vld([1234]|[234]lane) and vst([1234]|[234]lane) instructions
This commit changes the interface of the vld[1234], vld[234]lane, and vst[1234],
vst[234]lane ARM neon intrinsics and associates an address space with the
pointer that these intrinsics take. This changes, e.g.,

<2 x i32> @llvm.arm.neon.vld1.v2i32(i8*, i32)

to

<2 x i32> @llvm.arm.neon.vld1.v2i32.p0i8(i8*, i32)

This change ensures that address spaces are fully taken into account in the ARM
target during lowering of interleaved loads and stores.

Differential Revision: http://reviews.llvm.org/D12985

llvm-svn: 248887
2015-09-30 10:56:37 +00:00
Cong Hou f9f9ffb98b Scaling up values in ARMBaseInstrInfo::isProfitableToIfCvt() before they are scaled by a probability to avoid precision issue.
In ARMBaseInstrInfo::isProfitableToIfCvt(), there is a simple cost model in which the number of cycles is scaled by a probability to estimate the cost. However, when the number of cycles is small (which is usually the case), there is a precision issue after the computation. To avoid this issue, this patch scales those cycles by 1024 (chosen to make the multiplication a litter faster) before they are scaled by the probability. Other variables are also scaled up for the final comparison.

Differential Revision: http://reviews.llvm.org/D12742

llvm-svn: 248018
2015-09-18 18:19:40 +00:00
Cong Hou 511298b919 Distribute the weight on the edge from switch to default statement to edges generated in lowering switch.
Currently, when edge weights are assigned to edges that are created when lowering switch statement, the weight on the edge to default statement (let's call it "default weight" here) is not considered. We need to distribute this weight properly. However, without value profiling, we have no idea how to distribute it. In this patch, I applied the heuristic that this weight is evenly distributed to successors.

For example, given a switch statement with cases 1,2,3,5,10,11,20, and every edge from switch to each successor has weight 10. If there is a binary search tree built to test if n < 10, then its two out-edges will have weight 4x10+10/2 = 45 and 3x10 + 10/2 = 35 respectively (currently they are 40 and 30 without considering the default weight). Each distribution (which is 5 here) will be stored in each SwitchWorkListItem for further distribution.

There are some exceptions:

For a jump table header which doesn't have any edge to default statement, we don't distribute the default weight to it.
For a bit test header which covers a contiguous range and hence has no edges to default statement, we don't distribute the default weight to it.
When the branch checks a single value or a contiguous range with no edge to default statement, we don't distribute the default weight to it.
In other cases, the default weight is evenly distributed to successors.

Differential Revision: http://reviews.llvm.org/D12418

llvm-svn: 246522
2015-09-01 01:42:16 +00:00
Matthias Braun e40d89ef9b ARMLoadStoreOptimizer: Create LDRD/STRD on thumb2
Re-apply r241926 with an additional check that r13 and r15 are not used
for LDRD/STRD. See http://llvm.org/PR24190. This also already includes
the fix from r241951.

Differential Revision: http://reviews.llvm.org/D10623

llvm-svn: 242742
2015-07-21 00:18:59 +00:00
Matthias Braun 731e359e70 Revert "ARMLoadStoreOptimizer: Create LDRD/STRD on thumb2"
This reverts commit r241926. This caused http://llvm.org/PR24190

llvm-svn: 242735
2015-07-20 23:17:20 +00:00
Matthias Braun 141d1c9d8f ARM: Add scheduling information for LDRLIT instructions to swift scheduling model
These pseudo instructions are only lowered after register allocation and
are therefore still present when the machine scheduler runs.
Add a run: line to a testcase that uses the uncommon flags necessary to
actually produce a LDRLIT instruction on swift.

llvm-svn: 242587
2015-07-17 23:18:26 +00:00
Matthias Braun da3d0d7342 Arm: Don't define a label twice with two setjmps in a function.
Constructing a name based on the function name didn't give us a unique
symbol if we had more than one setjmp in a function. Using
MCContext::createTempSymbol() always gives us a unique name.

Differential Revision: http://reviews.llvm.org/D9314

llvm-svn: 242482
2015-07-16 22:34:20 +00:00
Alexey Bataev b9288601a3 [SDAG] Optimize unordered comparison in soft-float mode (patch by Anton Nadolskiy)
Current implementation handles unordered comparison poorly in soft-float mode. 
Consider (a ULE b) which is a <= b. It is lowered to (ledf2(a, b) <= 0 || unorddf2(a, b) != 0) (in general). We can do better job by lowering it to (__gtdf2(a, b) <= 0). 
Such replacement is true for other CMP's (ult, ugt, uge). In general, we just call same function as for ordered case but negate comparison against zero.
Differential Revision: http://reviews.llvm.org/D10804

llvm-svn: 242280
2015-07-15 08:39:35 +00:00
Matthias Braun 75e668ea6e Revert "LegalizeDAG: Fix and improve FCOPYSIGN/FABS legalization"
Accidental commit, needs review first.

This reverts commit r242107.

llvm-svn: 242108
2015-07-14 02:09:57 +00:00
Matthias Braun 4ac4ecdadf LegalizeDAG: Fix and improve FCOPYSIGN/FABS legalization
- Factor out code to query and modify the sign bit of a floatingpoint
  value as an integer. This also works if none of the targets integer
  types is big enough to hold all bits of the floatingpoint value.

- Legalize FABS(x) as FCOPYSIGN(x, 0.0) if FCOPYSIGN is available,
  otherwise perform bit manipulation on the sign bit. The previous code
  used "x >u 0 ? x : -x" which is incorrect for x being -0.0! It also
  takes 34 instructions on ARM Cortex-M4. With this patch we only
  require 5:
    vldr d0, LCPI0_0
    vmov r2, r3, d0
    lsrs r2, r3, #31
    bfi r1, r2, #31, #1
    bx lr
  (This could be further improved if the compiler would recognize that
   r2, r3 is zero).

- Only lower FCOPYSIGN(x, y) = sign(x) ? -FABS(x) : FABS(x) if FABS is
  available otherwise perform bit manipulation on the sign bit.

- Perform the sign(x) test by masking out the sign bit and comparing
  with 0 rather than shifting the sign bit to the highest position and
  testing for "<s 0". For x86 copysignl (on 80bit values) this gets us:
    testl $32768, %eax
  rather than:
    shlq $48, %rax
    sets %al
    testb %al, %al

llvm-svn: 242107
2015-07-14 02:08:26 +00:00
Matthias Braun e4ba6b8c24 ARMLoadStoreOptimizer: Create LDRD/STRD on thumb2
Differential Revision: http://reviews.llvm.org/D10623

llvm-svn: 241926
2015-07-10 18:28:49 +00:00
Matthias Braun ba3ecc3c80 ARMLoadStoreOptimizer: Fix errata 602117 handling and make testcase actually test for it
This fixes PR23912

Differential Revision: http://reviews.llvm.org/D10620

llvm-svn: 240582
2015-06-24 20:03:27 +00:00
David Majnemer 7fddeccb8b Move the personality function from LandingPadInst to Function
The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

llvm-svn: 239940
2015-06-17 20:52:32 +00:00
Matthias Braun 125c9f5f7b ARM: Thumb2 LDRD/STRD supports independent input/output regs
The existing code would unnecessarily break LDRD/STRD apart with
non-adjacent registers, on thumb2 this is not necessary.

Ideally on thumb2 we shouldn't match for ldrd/strd pre-regalloc anymore
as there is not reason to set register hints anymore, changing that is
something for a future patch however.

Differential Revision: http://reviews.llvm.org/D9694

Recommiting after the revert in r238821, the buildbot still failed with
the patch removed so there seems to be another reason for the breakage.

llvm-svn: 238935
2015-06-03 16:30:24 +00:00
Renato Golin 3a7bec86bd Revert "ARM: Thumb2 LDRD/STRD supports independent input/output regs"
This reverts commit r238795, as it broke the Thumb2 self-hosting buildbot.

Since self-hosting issues with Clang are hard to investigate, I'm taking the
liberty to revert now, so we can investigate it offline.

llvm-svn: 238821
2015-06-02 11:47:30 +00:00
Matthias Braun e20dc1cd3a ARM: Thumb2 LDRD/STRD supports independent input/output regs
The existing code would unnecessarily break LDRD/STRD apart with
non-adjacent registers, on thumb2 this is not necessary.

Ideally on thumb2 we shouldn't match for ldrd/strd pre-regalloc anymore
as there is not reason to set register hints anymore, changing that is
something for a future patch however.

Differential Revision: http://reviews.llvm.org/D9694

llvm-svn: 238795
2015-06-01 23:27:08 +00:00
Tim Northover a603c4076c ARM: recommit r237590: allow jump tables to be placed as constant islands.
The original version didn't properly account for the base register
being modified before the final jump, so caused miscompilations in
Chromium and LLVM. I've fixed this and tested with an LLVM self-host
(I don't have the means to build & test Chromium).

The general idea remains the same: in pathological cases jump tables
can be too far away from the instructions referencing them (like other
constants) so they need to be movable.

Should fix PR23627.

llvm-svn: 238680
2015-05-31 19:22:07 +00:00
Peter Collingbourne 7e814d100b Revert r237590, "ARM: allow jump tables to be placed as constant islands."
Caused a miscompile of the Android port of Chromium, details
forthcoming.

llvm-svn: 237972
2015-05-21 23:20:55 +00:00
Tim Northover 12c41af07c ARM: allow jump tables to be placed as constant islands.
Previously, they were forced to immediately follow the actual branch
instruction. This was usually OK (the LEAs actually accessing them got emitted
nearby, and weren't usually separated much afterwards). Unfortunately, a
sufficiently nasty phi elimination dumps many instructions right before the
basic block terminator, and this can increase the range too much.

This patch frees them up to be placed as usual by the constant islands pass,
and consequently has to slightly modify the form of TBB/TBH tables to refer to
a PC-relative label at the final jump. The other jump table formats were
already position-independent.

rdar://20813304

llvm-svn: 237590
2015-05-18 17:10:40 +00:00
Peter Collingbourne 85a0e23bc8 Thumb2SizeReduction: Check the correct set of registers for LDMIA.
The register set for LDMIA begins at offset 3, not 4. We were previously
missing the short encoding of this instruction in the case where the base
register was the first register in the register set.

Also clean up some dead code:

- The isARMLowRegister check is redundant with what VerifyLowRegs does;
  replace with an assert.
- Remove handling of LDMDB instruction, which has no short encoding (and
  does not appear in ReduceTable).

Differential Revision: http://reviews.llvm.org/D9485

llvm-svn: 236535
2015-05-05 20:07:10 +00:00
Peter Collingbourne 167668f8c8 Thumb2: When applying branch optimizations, visit branches in reverse order.
The order in which branches appear in ImmBranches is approximately their
order within the function body. By visiting later branches first, we reduce
the distance between earlier forward branches and their targets, making it
more likely that the cbn?z optimization, which can only apply to forward
branches, will succeed for those earlier branches.

Differential Revision: http://reviews.llvm.org/D9185

llvm-svn: 235640
2015-04-23 20:31:35 +00:00
Peter Collingbourne cfee5b04bc ARM: When re-creating a branch via InsertBranch, preserve CPSR flags.
In particular, this preserves the kill flag, which allows the Thumb2 cbn?z
optimization to be applied in cases where a branch has been re-created after
the live variables analysis pass, e.g. by the machine block placement pass.

This appears to be low risk; a number of other targets seem to already be
doing something similar, e.g. AArch64, PowerPC.

Differential Revision: http://reviews.llvm.org/D9184

llvm-svn: 235639
2015-04-23 20:31:32 +00:00
Peter Collingbourne 6529523151 Thumb2: When optimizing for size, do not if-convert branches involving comparisons with zero.
This allows the constant island pass to lower these branches to cbn?z
instructions, resulting in a shorter instruction sequence.

Differential Revision: http://reviews.llvm.org/D9183

llvm-svn: 235638
2015-04-23 20:31:30 +00:00
Peter Collingbourne 78f1ecc59c ARM: When spilling extra registers for alignment, prefer low registers on all Thumb targets.
This makes it more likely that we can use the 16-bit push and pop instructions
on Thumb-2, saving around 4 bytes per function.

Differential Revision: http://reviews.llvm.org/D9165

llvm-svn: 235637
2015-04-23 20:31:26 +00:00
David Blaikie 23af64846f [opaque pointer type] Add textual IR support for explicit type parameter to the call instruction
See r230786 and r230794 for similar changes to gep and load
respectively.

Call is a bit different because it often doesn't have a single explicit
type - usually the type is deduced from the arguments, and just the
return type is explicit. In those cases there's no need to change the
IR.

When that's not the case, the IR usually contains the pointer type of
the first operand - but since typed pointers are going away, that
representation is insufficient so I'm just stripping the "pointerness"
of the explicit type away.

This does make the IR a bit weird - it /sort of/ reads like the type of
the first operand: "call void () %x(" but %x is actually of type "void
()*" and will eventually be just of type "ptr". But this seems not too
bad and I don't think it would benefit from repeating the type
("void (), void () * %x(" and then eventually "void (), ptr %x(") as has
been done with gep and load.

This also has a side benefit: since the explicit type is no longer a
pointer, there's no ambiguity between an explicit type and a function
that returns a function pointer. Previously this case needed an explicit
type (eg: a function returning a void() function was written as
"call void () () * @x(" rather than "call void () * @x(" because of the
ambiguity between a function returning a pointer to a void() function
and a function returning void).

No ambiguity means even function pointer return types can just be
written alone, without writing the whole function's type.

This leaves /only/ the varargs case where the explicit type is required.

Given the special type syntax in call instructions, the regex-fu used
for migration was a bit more involved in its own unique way (as every
one of these is) so here it is. Use it in conjunction with the apply.sh
script and associated find/xargs commands I've provided in rr230786 to
migrate your out of tree tests. Do let me know if any of this doesn't
cover your cases & we can iterate on a more general script/regexes to
help others with out of tree tests.

About 9 test cases couldn't be automatically migrated - half of those
were functions returning function pointers, where I just had to manually
delete the function argument types now that we didn't need an explicit
function type there. The other half were typedefs of function types used
in calls - just had to manually drop the * from those.

import fileinput
import sys
import re

pat = re.compile(r'((?:=|:|^|\s)call\s(?:[^@]*?))(\s*$|\s*(?:(?:\[\[[a-zA-Z0-9_]+\]\]|[@%](?:(")?[\\\?@a-zA-Z0-9_.]*?(?(3)"|)|{{.*}}))(?:\(|$)|undef|inttoptr|bitcast|null|asm).*$)')
addrspace_end = re.compile(r"addrspace\(\d+\)\s*\*$")
func_end = re.compile("(?:void.*|\)\s*)\*$")

def conv(match, line):
  if not match or re.search(addrspace_end, match.group(1)) or not re.search(func_end, match.group(1)):
    return line
  return line[:match.start()] + match.group(1)[:match.group(1).rfind('*')].rstrip() + match.group(2) + line[match.end():]

for line in sys.stdin:
  sys.stdout.write(conv(re.search(pat, line), line))

llvm-svn: 235145
2015-04-16 23:24:18 +00:00
Javed Absar 5c5e3c5e36 [ARM] support for Cortex-R4/R4F
Currently, llvm (backend) doesn't know cortex-r4, even though it is the
default target for armv7r. Using "--target=armv7r-arm-none-eabi" provokes
'cortex-r4' is not a recognized processor for this target' by llvm.
This patch adds support for cortex-r4 and, very closely related, r4f.

llvm-svn: 234486
2015-04-09 14:07:28 +00:00
Owen Anderson db4201235b Fix a nasty bug in DAGCombine of STORE nodes.
This is very related to the bug fixed in r174431.  The problem is that
SelectionDAG does not include alignment in the uniquing of loads and
stores.  When an otherwise no-op DAGCombine would increase the alignment
of a load or store, the original node would be returned (with the
alignment increased), which would cause the node not to be processed by
any further DAGCombines.

I don't have a direct testcase for this that manifests on an in-tree
target, but I did see some noise in the tests for other targets and have
updated them for it.

llvm-svn: 232780
2015-03-19 22:48:57 +00:00
David Blaikie f72d05bc7b [opaque pointer type] Add textual IR support for explicit type parameter to gep operator
Similar to gep (r230786) and load (r230794) changes.

Similar migration script can be used to update test cases, which
successfully migrated all of LLVM and Polly, but about 4 test cases
needed manually changes in Clang.

(this script will read the contents of stdin and massage it into stdout
- wrap it in the 'apply.sh' script shown in previous commits + xargs to
apply it over a large set of test cases)

import fileinput
import sys
import re

rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL)

def conv(match):
  line = match.group(1)
  line += match.group(4)
  line += ", "
  line += match.group(2)
  return line

line = sys.stdin.read()
off = 0
for match in re.finditer(rep, line):
  sys.stdout.write(line[off:match.start()])
  sys.stdout.write(conv(match))
  off = match.end()
sys.stdout.write(line[off:])

llvm-svn: 232184
2015-03-13 18:20:45 +00:00
Mehdi Amini 46a43556db Make DataLayout Non-Optional in the Module
Summary:
DataLayout keeps the string used for its creation.

As a side effect it is no longer needed in the Module.
This is "almost" NFC, the string is no longer
canonicalized, you can't rely on two "equals" DataLayout
having the same string returned by getStringRepresentation().

Get rid of DataLayoutPass: the DataLayout is in the Module

The DataLayout is "per-module", let's enforce this by not
duplicating it more than necessary.
One more step toward non-optionality of the DataLayout in the
module.

Make DataLayout Non-Optional in the Module

Module->getDataLayout() will never returns nullptr anymore.

Reviewers: echristo

Subscribers: resistor, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D7992

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231270
2015-03-04 18:43:29 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +00:00
David Blaikie 79e6c74981 [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction
One of several parallel first steps to remove the target type of pointers,
replacing them with a single opaque pointer type.

This adds an explicit type parameter to the gep instruction so that when the
first parameter becomes an opaque pointer type, the type to gep through is
still available to the instructions.

* This doesn't modify gep operators, only instructions (operators will be
  handled separately)

* Textual IR changes only. Bitcode (including upgrade) and changing the
  in-memory representation will be in separate changes.

* geps of vectors are transformed as:
    getelementptr <4 x float*> %x, ...
  ->getelementptr float, <4 x float*> %x, ...
  Then, once the opaque pointer type is introduced, this will ultimately look
  like:
    getelementptr float, <4 x ptr> %x
  with the unambiguous interpretation that it is a vector of pointers to float.

* address spaces remain on the pointer, not the type:
    getelementptr float addrspace(1)* %x
  ->getelementptr float, float addrspace(1)* %x
  Then, eventually:
    getelementptr float, ptr addrspace(1) %x

Importantly, the massive amount of test case churn has been automated by
same crappy python code. I had to manually update a few test cases that
wouldn't fit the script's model (r228970,r229196,r229197,r229198). The
python script just massages stdin and writes the result to stdout, I
then wrapped that in a shell script to handle replacing files, then
using the usual find+xargs to migrate all the files.

update.py:
import fileinput
import sys
import re

ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")
normrep = re.compile(       r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")

def conv(match, line):
  if not match:
    return line
  line = match.groups()[0]
  if len(match.groups()[5]) == 0:
    line += match.groups()[2]
  line += match.groups()[3]
  line += ", "
  line += match.groups()[1]
  line += "\n"
  return line

for line in sys.stdin:
  if line.find("getelementptr ") == line.find("getelementptr inbounds"):
    if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("):
      line = conv(re.match(ibrep, line), line)
  elif line.find("getelementptr ") != line.find("getelementptr ("):
    line = conv(re.match(normrep, line), line)
  sys.stdout.write(line)

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

After that, check-all (with llvm, clang, clang-tools-extra, lld,
compiler-rt, and polly all checked out).

The extra 'rm' in the apply.sh script is due to a few files in clang's test
suite using interesting unicode stuff that my python script was throwing
exceptions on. None of those files needed to be migrated, so it seemed
sufficient to ignore those cases.

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7636

llvm-svn: 230786
2015-02-27 19:29:02 +00:00
Mehdi Amini 945a660cbc Change the fast-isel-abort option from bool to int to enable "levels"
Summary:
Currently fast-isel-abort will only abort for regular instructions,
and just warn for function calls, terminators, function arguments.
There is already fast-isel-abort-args but nothing for calls and
terminators.

This change turns the fast-isel-abort options into an integer option,
so that multiple levels of strictness can be defined.
This will help no being surprised when the "abort" option indeed does
not abort, and enables the possibility to write test that verifies
that no intrinsics are forgotten by fast-isel.

Reviewers: resistor, echristo

Subscribers: jfb, llvm-commits

Differential Revision: http://reviews.llvm.org/D7941

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 230775
2015-02-27 18:32:11 +00:00
James Molloy 99f06df8ac Make buildbots better.
This testcase change was associated incorrectly to a followup commit in my git tree, not the base commit. Sorry!

llvm-svn: 228827
2015-02-11 12:24:09 +00:00
Akira Hatanaka 442b40c2eb [ARM] Fix a bug in constant island pass that was triggering an assertion.
The assert was being triggered when the distance between a constant pool entry
and its user exceeded the maximally allowed distance after thumb2 branch
shortening. A padding was inserted after a thumb2 branch instruction was shrunk,
which caused the user to be out of range. This is wrong as the padding should
have been inserted by the layout algorithm so that the distance between two
instructions doesn't grow later during thumb2 instruction optimization.

This commit fixes the code in ARMConstantIslands::createNewWater to call
computeBlockSize and set BasicBlock::Unalign when a branch instruction is
inserted to create new water after a basic block. A non-zero Unalign causes
the worst-case padding to be inserted when adjustBBOffsetsAfter is called to
recompute the basic block offsets.

rdar://problem/19130476

llvm-svn: 225467
2015-01-08 20:44:50 +00:00
Kristof Beyls 933de7aa06 Fix large stack alignment codegen for ARM and Thumb2 targets
This partially fixes PR13007 (ARM CodeGen fails with large stack
alignment): for ARM and Thumb2 targets, but not for Thumb1, as it
seems stack alignment for Thumb1 targets hasn't been supported at
all.

Producing an aligned stack pointer is done by zero-ing out the lower
bits of the stack pointer. The BIC instruction was used for this.
However, the immediate field of the BIC instruction only allows to
encode an immediate that can zero out up to a maximum of the 8 lower
bits. When a larger alignment is requested, a BIC instruction cannot
be used; llvm was silently producing incorrect code in this case.

This commit fixes code generation for large stack aligments by
using the BFC instruction instead, when the BFC instruction is
available.  When not, it uses 2 instructions: a right shift,
followed by a left shift to zero out the lower bits.

The lowering of ARM::Int_eh_sjlj_dispatchsetup still has code
that unconditionally uses BIC to realign the stack pointer, so it
very likely has the same problem. However, I wasn't able to
produce a test case for that. This commit adds an assert so that
the compiler will fail the assert instead of silently generating
wrong code if this is ever reached.

llvm-svn: 225446
2015-01-08 15:09:14 +00:00
Duncan P. N. Exon Smith be7ea19b58 IR: Make metadata typeless in assembly
Now that `Metadata` is typeless, reflect that in the assembly.  These
are the matching assembly changes for the metadata/value split in
r223802.

  - Only use the `metadata` type when referencing metadata from a call
    intrinsic -- i.e., only when it's used as a `Value`.

  - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode`
    when referencing it from call intrinsics.

So, assembly like this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata !{i32 %v}, metadata !0)
      call void @llvm.foo(metadata !{i32 7}, metadata !0)
      call void @llvm.foo(metadata !1, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{metadata !3}, metadata !0)
      ret void, !bar !2
    }
    !0 = metadata !{metadata !2}
    !1 = metadata !{i32* @global}
    !2 = metadata !{metadata !3}
    !3 = metadata !{}

turns into this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata i32 %v, metadata !0)
      call void @llvm.foo(metadata i32 7, metadata !0)
      call void @llvm.foo(metadata i32* @global, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{!3}, metadata !0)
      ret void, !bar !2
    }
    !0 = !{!2}
    !1 = !{i32* @global}
    !2 = !{!3}
    !3 = !{}

I wrote an upgrade script that handled almost all of the tests in llvm
and many of the tests in cfe (even handling many `CHECK` lines).  I've
attached it (or will attach it in a moment if you're speedy) to PR21532
to help everyone update their out-of-tree testcases.

This is part of PR21532.

llvm-svn: 224257
2014-12-15 19:07:53 +00:00
Chad Rosier 620fb2206d [ARMConstantIsland] Insert tbb/tbh optimization where previous jump table resided.
llvm-svn: 224165
2014-12-12 23:27:40 +00:00
Tim Northover 631cc9ce1a ARM: allow constpool entry to be moved to the user's block in all cases.
Normally entries can only move to a lower address, but when that wasn't viable,
the user's block was considered anyway. Unfortunately, it went via
createNewWater which wasn't designed to handle the case where there's already
an island after the block.

Unfortunately, the test we have is slow and fragile, and I couldn't reduce it
to anything sane even with the @llvm.arm.space intrinsic. The test change here
is recreating the previous one after the change.

rdar://problem/18545506

llvm-svn: 221905
2014-11-13 17:58:53 +00:00
Akira Hatanaka 0d0c78180d ARM: Fix a bug which was causing convergence failure in constant-island pass.
The bug is in ARMConstantIslands::createNewWater where the upper bound of the
new water split point is computed:

// This could point off the end of the block if we've already got constant
// pool entries following this block; only the last one is in the water list.
// Back past any possible branches (allow for a conditional and a maximally
// long unconditional).
if (BaseInsertOffset + 8 >= UserBBI.postOffset()) {
  BaseInsertOffset = UserBBI.postOffset() - UPad - 8;
  DEBUG(dbgs() << format("Move inside block: %#x\n", BaseInsertOffset));
}

The split point is supposed to be somewhere between the machine instruction that
loads from the constant pool entry and the end of the basic block, before branch
instructions. The code above is fine if the basic block is large enough and
there are a sufficient number of instructions following the machine instruction.
However, if the machine instruction is near the end of the basic block,
BaseInsertOffset can point to the machine instruction or another instruction
that precedes it, and this can lead to convergence failure.

This commit fixes this bug by ensuring BaseInsertOffset is larger than the
offset of the instruction following the constant-loading instruction.

rdar://problem/18581150

llvm-svn: 220015
2014-10-17 01:31:47 +00:00
Rafael Espindola 11aaaeebe0 Delete -std-compile-opts.
These days -std-compile-opts was just a silly alias for -O3.

llvm-svn: 219951
2014-10-16 20:00:02 +00:00
Oliver Stannard d4e0a4fd2c [ARM] Allow selecting VRINT[APMXZR] and VCVT[BT] instructions for FPv5
Currently, we only codegen the VRINT[APMXZR] and VCVT[BT] instructions
when targeting ARMv8, but they are actually present on any target with
FP-ARMv8. Note that FP-ARMv8 is called FPv5 when is is part of an
M-profile core, but they have the same instructions so we model them
both as FPARMv8 in the ARM backend.

llvm-svn: 218763
2014-10-01 13:13:18 +00:00
Oliver Stannard 37e4daab05 [ARM] Add support for Cortex-M7, FPv5-SP and FPv5-DP (LLVM)
The Cortex-M7 has 3 options for its FPU: none, FPv5-SP-D16 and
FPv5-DP-D16. FPv5 has the same instructions as FP-ARMv8, so it can be
modelled using the same target feature, and all double-precision
operations are already disabled by the fp-only-sp target features.

llvm-svn: 218747
2014-10-01 09:02:17 +00:00
Reid Kleckner 2d9bb65b3d ARM / x86_64 varargs: Don't save regparms in prologue without va_start
There's no need to do this if the user doesn't call va_start. In the
future, we're going to have thunks that forward these register
parameters with musttail calls, and they won't need these spills for
handling va_start.

Most of the test suite changes are adding va_start calls to existing
tests to keep things working.

llvm-svn: 216294
2014-08-22 21:59:26 +00:00
Oliver Stannard 51b1d460cb [ARM] Enable DP copy, load and store instructions for FPv4-SP
The FPv4-SP floating-point unit is generally referred to as
single-precision only, but it does have double-precision registers and
load, store and GPR<->DPR move instructions which operate on them.
This patch enables the use of these registers, the main advantage of
which is that we now comply with the AAPCS-VFP calling convention.
This partially reverts r209650, which added some AAPCS-VFP support,
but did not handle return values or alignment of double arguments in
registers.

This patch also adds tests for Thumb2 code generation for
floating-point instructions and intrinsics, which previously only
existed for ARM.

llvm-svn: 216172
2014-08-21 12:50:31 +00:00
Tim Northover 2a417b96d4 ARM: do not generate BLX instructions on Cortex-M CPUs.
Particularly on MachO, we were generating "blx _dest" instructions on M-class
CPUs, which don't actually exist. They happen to get fixed up by the linker
into valid "bl _dest" instructions (which is why such a massive issue has
remained largely undetected), but we shouldn't rely on that.

llvm-svn: 214959
2014-08-06 11:13:14 +00:00
Akira Hatanaka dc08c30df9 [ARM] In dynamic-no-pic mode, ARM's post-RA pseudo expansion was incorrectly
expanding pseudo LOAD_STATCK_GUARD using instructions that are normally used
in pic mode. This patch fixes the bug.

<rdar://problem/17886592>

llvm-svn: 214614
2014-08-02 05:40:40 +00:00
Akira Hatanaka ba3af24c25 [stack protector] Add test cases for thumb and thumb2.
<rdar://problem/12475629>

llvm-svn: 213970
2014-07-25 19:47:46 +00:00
Tim Northover 14ff2df05c ARM: spot SBFX-compatbile code expressed with sign_extend_inreg
We were assuming all SBFX-like operations would have the shl/asr form, but
often when the field being extracted is an i8 or i16, we end up with a
SIGN_EXTEND_INREG acting on a shift instead. Simple enough to check for though.

llvm-svn: 213754
2014-07-23 13:59:12 +00:00
Tim Northover 7ad2a0e0c2 ARM: add patterns for [su]xta[bh] from just a shift.
Although the final shifter operand is a rotate, this actually only matters for
the half-word extends when the amount == 24. Otherwise folding a shift in is
just as good.

llvm-svn: 213753
2014-07-23 13:59:07 +00:00
Chandler Carruth 9a0051cd59 [SDAG] Make the DAGCombine worklist not grow endlessly due to duplicate
insertions.

The old behavior could cause arbitrarily bad memory usage in the DAG
combiner if there was heavy traffic of adding nodes already on the
worklist to it. This commit switches the DAG combine worklist to work
the same way as the instcombine worklist where we null-out removed
entries and only add new entries to the worklist. My measurements of
codegen time shows slight improvement. The memory utilization is
unsurprisingly dominated by other factors (the IR and DAG itself
I suspect).

This change results in subtle, frustrating churn in the particular order
in which DAG combines are applied which causes a number of minor
regressions where we fail to match a pattern previously matched by
accident. AFAICT, all of these should be using AddToWorklist to directly
or should be written in a less brittle way. None of the changes seem
drastically bad, and a few of the changes seem distinctly better.

A major change required to make this work is to significantly harden the
way in which the DAG combiner handle nodes which become dead
(zero-uses). Previously, we relied on the ability to "priority-bump"
them on the combine worklist to achieve recursive deletion of these
nodes and ensure that the frontier of remaining live nodes all were
added to the worklist. Instead, I've introduced a routine to just
implement that precise logic with no indirection. It is a significantly
simpler operation than that of the combiner worklist proper. I suspect
this will also fix some other problems with the combiner.

I think the x86 changes are really minor and uninteresting, but the
avx512 change at least is hiding a "regression" (despite the test case
being just noise, not testing some performance invariant) that might be
looked into. Not sure if any of the others impact specific "important"
code paths, but they didn't look terribly interesting to me, or the
changes were really minor. The consensus in review is to fix any
regressions that show up after the fact here.

Thanks to the other reviewers for checking the output on other
architectures. There is a specific regression on ARM that Tim already
has a fix prepped to commit.

Differential Revision: http://reviews.llvm.org/D4616

llvm-svn: 213727
2014-07-23 07:08:53 +00:00
Christian Pirker c6308f59b2 ARM: Fix TPsoft for Thumb mode
Reviewed at http://reviews.llvm.org/D4230

llvm-svn: 211601
2014-06-24 15:45:59 +00:00
Alp Toker d3d017cf00 Reduce verbiage of lit.local.cfg files
We can just split targets_to_build in one place and make it immutable.

llvm-svn: 210496
2014-06-09 22:42:55 +00:00
Tim Northover b4ddc0845a ARM & AArch64: make use of common cmpxchg idioms after expansion
The C and C++ semantics for compare_exchange require it to return a bool
indicating success. This gets mapped to LLVM IR which follows each cmpxchg with
an icmp of the value loaded against the desired value.

When lowered to ldxr/stxr loops, this extra comparison is redundant: its
results are implicit in the control-flow of the function.

This commit makes two changes: it replaces that icmp with appropriate PHI
nodes, and then makes sure earlyCSE is called after expansion to actually make
use of the opportunities revealed.

I've also added -{arm,aarch64}-enable-atomic-tidy options, so that
existing fragile tests aren't perturbed too much by the change. Many
of them either rely on undef/unreachable too pervasively to be
restored to something well-defined (particularly while making sure
they test the same obscure assert from many years ago), or depend on a
particular CFG shape, which is disrupted by SimplifyCFG.

rdar://problem/16227836

llvm-svn: 209883
2014-05-30 10:09:59 +00:00
James Molloy 556763d2ef Fix the Load/Store optimization pass to work with Thumb1.
Patch by Moritz Roth!

llvm-svn: 208992
2014-05-16 14:14:30 +00:00
Reid Kleckner 9c6582129a Move the segmented stack switch to a function attribute
This removes the -segmented-stacks command line flag in favor of a
per-function "split-stack" attribute.

Patch by Luqman Aden and Alex Crichton!

llvm-svn: 205997
2014-04-10 22:58:43 +00:00
Saleem Abdulrasool c351ed2966 ARM: fix test case missed in previous roundup
This should hopefully bring the last MSVC buildbot back to green!

llvm-svn: 205596
2014-04-04 01:19:56 +00:00
Saleem Abdulrasool 905b6d192c ARM: yet another round of ARM test clean ups
llvm-svn: 205586
2014-04-03 23:47:24 +00:00
Saleem Abdulrasool 717c991923 ARM: update even more tests
More updating of tests to be explicit about the target triple rather than
relying on the default target triple supporting ARM mode.

Indicate to lit that object emission is not yet available for Windows on ARM.

llvm-svn: 205545
2014-04-03 17:35:22 +00:00
Oliver Stannard b14c625111 ARM: Add support for segmented stacks
Patch by Alex Crichton, ILyoan, Luqman Aden and Svetoslav.

llvm-svn: 205430
2014-04-02 16:10:33 +00:00
Artyom Skrobov 1a6cd1d912 ARMv8 IfConversion must skip narrow instructions that a) define CPSR and b) wouldn't affect CPSR in an IT block
llvm-svn: 202257
2014-02-26 11:27:28 +00:00
Nico Rieck 5ba5226ab9 Add extra CHECK prefix to tests with explicit prefix
These tests mistakenly assume that CHECK is still available even if an
explicit prefix is specified.

llvm-svn: 201492
2014-02-16 13:28:15 +00:00
Renato Golin 78a6eba862 Remove -arm-disable-ehabi option
llvm-svn: 200988
2014-02-07 20:12:49 +00:00
Manman Ren b681918ddd PGO branch weight: update edge weights in IfConverter.
This commit only handles IfConvertTriangle. To update edge weights
of a successor, one interface is added to MachineBasicBlock:
/// Set successor weight of a given iterator.
setSuccWeight(succ_iterator I, uint32_t weight)

An existing testing case test/CodeGen/Thumb2/v8_IT_5.ll is updated,
since we now correctly update the edge weights, the cold block
is placed at the end of the function and we jump to the cold block.

llvm-svn: 200428
2014-01-29 23:18:47 +00:00
Renato Golin 8cea6e8fc6 Enable EHABI by default
After all hard work to implement the EHABI and with the test-suite
passing, it's time to turn it on by default and allow users to
disable it as a work-around while we fix the eventual bugs that show
up.

This commit also remove the -arm-enable-ehabi-descriptors, since we
want the tables to be printed every time the EHABI is turned on
for non-Darwin ARM targets.

Although MCJIT EHABI is not working yet (needs linking with the right
libraries), this commit also fixes some relocations on MCJIT regarding
the EH tables/lib calls, and update some tests to avoid using EH tables
when none are needed.

The EH tests in the test-suite that were previously disabled on ARM
now pass with these changes, so a follow-up commit on the test-suite
will re-enable them.

llvm-svn: 200388
2014-01-29 11:50:56 +00:00
Weiming Zhao 5930ae6cc2 [Thumbv8] Fix the value of BLXOperandIndex of isV8EligibleForIT
Originally, BLX was passed as operand #0 in MachineInstr and as operand
#2 in MCInst. But now, it's operand #2 in both cases.

This patch also removes unnecessary FileCheck in the test case added by r199127.

llvm-svn: 199928
2014-01-23 19:55:33 +00:00
Weiming Zhao f66be56bf7 Fix PR 18369: [Thumbv8] asserts due to inconsistent CPSR liveness of IT blocks
The issue is caused when Post-RA scheduler reorders a bundle instruction
(IT block). However, it only flips the CPSR liveness of the bundle instruction,
leaves the instructions inside the bundle unchanged, which causes inconstancy and crashes
Thumb2SizeReduction.cpp::ReduceMBB().

llvm-svn: 199127
2014-01-13 18:47:54 +00:00
Benjamin Kramer c10563d14e Fix broken CHECK lines.
llvm-svn: 199016
2014-01-11 21:06:00 +00:00
Joerg Sonnenberger 002a14765e Enabling thumb2 mode used to force support for armv6t2. Replace this
with a temporary assertion and adjust the various test cases.

llvm-svn: 197224
2013-12-13 11:16:00 +00:00
David Peixotto 8ad70b3542 Add support for parsing ARM symbol variants on ELF targets
ARM symbol variants are written with parens instead of @ like this:

  .word __GLOBAL_I_a(target1)

This commit adds support for parsing these symbol variants in
expressions. We introduce a new flag to MCAsmInfo that indicates the
parser should use parens to parse the symbol variant. The expression
parser is modified to look for symbol variants using parens instead
of @ when the corresponding MCAsmInfo flag is true.

The MCAsmInfo parens flag is enabled only for ARM on ELF.

By adding this flag to MCAsmInfo, we are able to get rid of
redundant ARM-specific symbol variants and use the generic variants
instead (e.g. VK_GOT instead of VK_ARM_GOT). We use the new
UseParensForSymbolVariant attribute in MCAsmInfo to correctly print
the symbol variants for arm.

To achive this we need to keep a handle to the MCAsmInfo in the
MCSymbolRefExpr class that we can check when printing the symbol
variant.

Updated Tests:
  Changed case of symbol variant to match the generic kind.
  test/CodeGen/ARM/tls-models.ll
  test/CodeGen/ARM/tls1.ll
  test/CodeGen/ARM/tls2.ll
  test/CodeGen/Thumb2/tls1.ll
  test/CodeGen/Thumb2/tls2.ll

PR18080

llvm-svn: 196424
2013-12-04 22:43:20 +00:00