4768 Commits

Author SHA1 Message Date
Robert Lougher
5a2ae98407 Test commit - added a new line to vec_shuf-insert.ll.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201083 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-10 12:42:13 +00:00
Elena Demikhovsky
27ef6eec41 AVX-512: Fixed extract_vector_elt for v16i1 and v8i1 vectors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201066 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-10 07:02:39 +00:00
Rafael Espindola
26baaa1efb Always create a temporary symbol to use with the cfi frame.
This is a small simplification and a small step in fixing pr18743 since
private functions on MachO should be using a 'l' prefix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200994 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-07 21:23:18 +00:00
Rafael Espindola
d413950a93 Use FileCheck variables to simplify this test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200992 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-07 21:11:33 +00:00
Rafael Espindola
0732e94378 Fix a bug with .weak_def_can_be_hidden: Mutable variables cannot use it.
Thanks to John McCall for noticing it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200977 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-07 16:21:30 +00:00
Jim Grosbach
1f65cfad96 X86: Resolve a long standing FIXME and properly isel pextr[bw].
Generalize the AArch64 .td nodes for AssertZext and AssertSext. Use
them to match the relevant pextr store instructions.

The test widen_load-2.ll requires a slight change because with the
stores gone, the remaining instructions are scheduled in a different
order.

Add test cases for SSE4 and AVX variants.

Resolves rdar://13414672.

Patch by Adam Nemet <anemet@apple.com>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200957 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-07 00:16:33 +00:00
Quentin Colombet
30c0f72237 [CodeGenPrepare] Move away sign extensions that get in the way of addressing
mode.

Basically the idea is to transform code like this:
%idx = add nsw i32 %a, 1
%sextidx = sext i32 %idx to i64
%gep = gep i8* %myArray, i64 %sextidx
load i8* %gep

Into:
%sexta = sext i32 %a to i64
%idx = add nsw i64 %sexta, 1
%gep = gep i8* %myArray, i64 %idx
load i8* %gep

That way the computation can be folded into the addressing mode.

This transformation is done as part of the addressing mode matcher.
If the matching fails (not profitable, addressing mode not legal, etc.), the
matcher will revert the related promotions.

<rdar://problem/15519855>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200947 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-06 21:44:56 +00:00
Quentin Colombet
1a10a51431 [RegAlloc] Add a last chance recoloring mechanism when everything else failed to
find a register.

The idea is to choose a color for the variable that cannot be allocated and
recolor its interferences around. Unlike the current register allocation scheme,
it is allowed to change the color of an already assigned (but maybe not
splittable or spillable) live interval while propagating this change to its
neighbors.
In other word, there are two things that may help finding an available color:
- Already assigned variables (RS_Done) can be recolored to different color.
- The recoloring allows to catch solutions that needs to touch more that just
  the neighbors of the current allocated variable.

E.g.,
vA can use {R1, R2    }
vB can use {    R2, R3}
vC can use {R1        }
Where vA, vB, and vC cannot be split anymore (they are reloads for instance) and
they all interfere.

vA is assigned R1
vB is assigned R2
vC tries to evict vA but vA is already done.
=> Regular register allocation heuristic fails.

Last chance recoloring kicks in:
vC does as if vA was evicted => vC uses R1.
vC is marked as fixed.
vA needs to find a color.
None are available.
vA cannot evict vC: vC is a fixed virtual register now.
vA does as if vB was evicted => vA uses R2.
vB needs to find a color.
R3 is available.
Recoloring => vC = R1, vA = R2, vB = R3.

<rdar://problem/15947839>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200883 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-05 22:13:59 +00:00
Rafael Espindola
f39297678b Remove support for not using .loc directives.
Clang itself was not using this. The only way to access it was via llc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200862 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-05 18:00:21 +00:00
Elena Demikhovsky
c341b7c0ef AVX-512: optimized icmp -> sext -> icmp pattern
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200849 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-05 16:17:36 +00:00
Elena Demikhovsky
002683abc7 AVX-512: Added intrinsic for cvtph2ps.
Added VPTESTNM instruction.
Added a pattern to vselect (lit tests will follow).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200823 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-05 07:05:03 +00:00
David Blaikie
cec7ce78d7 DebugInfo: Remove some unneeded conditionals now that DIBuilder no longer emits zero-length arrays as {i32 0}
A bunch of test cases needed to be cleaned up for this, many my fault -
when implementid imported modules I updated test cases by simply
duplicating the prior metadata field - which wasn't always the empty
metadata entry.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200731 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-04 01:23:52 +00:00
Hal Finkel
e6c04bff3c Expand vector bswap in LegalizeVectorOps
ISD::BSWAP was missing from the list of node types that should be expanded
element-wise.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200705 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-03 17:27:25 +00:00
Josh Magee
cde5c26c46 [stackprotector] Implement the sspstrong rules for stack layout.
This changes the PrologueEpilogInserter and LocalStackSlotAllocation passes to
follow the extended stack layout rules for sspstrong and sspreq.

The sspstrong layout rules are:
 1. Large arrays and structures containing large arrays (>= ssp-buffer-size)
are closest to the stack protector.
 2. Small arrays and structures containing small arrays (< ssp-buffer-size) are
2nd closest to the protector.
 3. Variables that have had their address taken are 3rd closest to the
protector.


Differential Revision: http://llvm-reviews.chandlerc.com/D2546


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200601 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-01 01:36:16 +00:00
Reid Kleckner
8a24e83550 Implement inalloca codegen for x86 with the new inalloca design
Calls with inalloca are lowered by skipping all stores for arguments
passed in memory and the initial stack adjustment to allocate argument
memory.

Now the frontend is responsible for the memory layout, and the backend
doesn't have to do any work.  As a result these changes are pretty
minimal.

Reviewers: echristo

Differential Revision: http://llvm-reviews.chandlerc.com/D2637

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200596 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-31 23:50:57 +00:00
Reid Kleckner
f10743d765 Don't put non-static allocas in the static alloca map
Allocas marked inalloca are never static, but we were trying to put them
into the static alloca map if they were in the entry block.  Also add an
assertion in x86 fastisel.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200593 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-31 23:45:12 +00:00
Reid Kleckner
9934ff2b7f Set -mcpu to make this test pass on atom bots
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200588 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-31 22:58:10 +00:00
Lang Hames
f96f832a3c Replace X86 FMA intrinsic pseduo-instructions with def pats.
It looks like these pseudos were only used for pattern matching. Def pats are
the appropriate way to do that. As a bonus, these intrinsics will now have
memory operands folded properly, and better FMA3 variants selected where
appropriate (see r199933).

<rdar://problem/15611947>



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200577 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-31 21:29:19 +00:00
Reid Kleckner
65c98b9da4 [ms-cxxabi] Add a new calling convention that swaps 'this' and 'sret'
MSVC always places the 'this' parameter for a method first.  The
implicit 'sret' pointer for methods always comes second.  We already
implement this for __thiscall by putting sret parameters on the stack,
but __cdecl methods require putting both parameters on the stack in
opposite order.

Using a special calling convention allows frontends to keep the sret
parameter first, which avoids breaking lots of assumptions in LLVM and
Clang.

Fixes PR15768 with the corresponding change in Clang.

Reviewers: ributzka, majnemer

Differential Revision: http://llvm-reviews.chandlerc.com/D2663

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200561 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-31 17:41:22 +00:00
Manman Ren
05324ab015 This patch teaches the DAGCombiner how to fold insert_subvector nodes
when the input is a concat_vectors and the insert replaces one of the
concat halves:

Lower half: fold (insert_subvector (concat_vectors X, Y), Z) ->
(concat_vectors Z, Y)
Upper half: fold (insert_subvector (concat_vectors X, Y), Z) ->
(concat_vectors X, Z)

This can be seen with the following IR:

define <8 x float> @lower_half(<4 x float> %v1, <4 x float> %v2, <4 x
float> %v3) {
  %1 = shufflevector <4 x float> %v1, <4 x float> %v2, <8 x i32> <i32
0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
  %2 = tail call <8 x float> @llvm.x86.avx.vinsertf128.ps.256(<8 x
float> %1, <4 x float> %v3, i8 0)

The vinsertf128 intrinsic is converted into an insert_subvector node
in SelectionDAGBuilder.cpp.

Using AVX, without the patch this generates two vinsertf128 instructions:

vinsertf128 $1, %xmm1, %ymm0, %ymm0
vinsertf128 $0, %xmm2, %ymm0, %ymm0

With the patch this is optimized into:

vinsertf128 $1, %xmm1, %ymm2, %ymm0

Patch by Robert Lougher.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200506 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-31 01:10:35 +00:00
Manman Ren
21f09088d3 PGO branch weight: update edge weights in SelectionDAGBuilder.
When converting from "or + br" to two branches, or converting from
"and + br" to two branches, we correctly update the edge weights of
the two branches.

The previous attempt at r200431 was reverted at r200434 because of
two testing case failures. I modified my patch a little, but forgot
to re-run "make check-all".

Testing case CodeGen/ARM/lsr-unfolded-offset.ll is updated because of
the patch's impact on branch probability which causes changes in
spill placement.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200502 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-31 00:42:44 +00:00
Juergen Ributzka
014fdcdaf0 [Stackmaps] Record the stack size of each function that contains a stackmap/patchpoint intrinsic.
Re-applying the patch, but this time without using AsmPrinter methods.

Reviewed by Andy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200481 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-30 18:58:27 +00:00
Juergen Ributzka
d26c0e731c Revert "[Stackmaps] Record the stack size of each function that contains a stackmap/patchpoint intrinsic."
This reverts commit r200444 to unbreak buildbots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200445 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-30 03:34:02 +00:00
Juergen Ributzka
2baaf25bf5 [Stackmaps] Record the stack size of each function that contains a stackmap/patchpoint intrinsic.
Reviewed by Andy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200444 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-30 03:06:14 +00:00
Manman Ren
2227f98e32 Revert r200431 due to bot failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200434 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-30 00:53:27 +00:00
Manman Ren
0bdaca5058 PGO branch weight: update edge weights in SelectionDAGBuilder.
When converting from "or + br" to two branches, or converting from
"and + br" to two branches, we correctly update the edge weights of
the two branches.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200431 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-30 00:24:37 +00:00
Rafael Espindola
916d3120b3 Use a raw_stream to implement the mangler.
This is a bit more convenient for some callers, but more importantly, it is
easier to implement correctly. Doing this removes the patching of already
printed data that was used for fastcall, fixing a crash with private fastcall
symbols.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200367 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-29 02:30:38 +00:00
Andrea Di Biagio
106b79744b [X86] Add extra rules for combining vselect dag nodes into movsd.
This improves the fix committed at revision 199683 adding the
following new target specific combine rules:

1) fold (v4i32: vselect <0,0,-1,-1>, A, B) ->
        (v4i32 (bitcast (movsd (v2i64 (bitcast A)), (v2i64 (bitcast B))) ))

2) fold (v4f32: vselect <0,0,-1,-1>, A, B) ->
        (v4f32 (bitcast (movsd (v2f64 (bitcast A)), (v2f64 (bitcast B))) ))

3) fold (v4i32: vselect <-1,-1,0,0>, A, B) ->
        (v4i32 (bitcast (movsd (v2i64 (bitcast B)), (v2i64 (bitcast A))) ))

4) fold (v4f32: vselect <-1,-1,0,0>, A, B) ->
        (v4f32 (bitcast (movsd (v2i64 (bitcast B)), (v2i64 (bitcast A))) ))




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200324 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-28 18:14:21 +00:00
Andrea Di Biagio
5144469bb4 [DAGCombiner] Avoid introducing an illegal build_vector when folding a sign_extend.
Make sure that we don't introduce illegal build_vector dag nodes
when trying to fold a sign_extend of a build_vector.

This fixes a regression introduced by r200234.
Added test CodeGen/X86/fold-vector-sext-crash.ll
to verify that llc no longer crashes with an assertion failure
due to an illegal build_vector of type MVT::v4i64.

Thanks to Ilia Filippov for spotting this regression and for
providing a reproducible test case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200313 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-28 12:53:56 +00:00
Andrea Di Biagio
e9c0b5aba6 [DAGCombiner] Teach how to fold sext/aext/zext of constant build vectors.
This patch teaches the DAGCombiner how to fold a sext/aext/zext dag node when
the operand in input is a build vector of constants (or UNDEFs).

The inability to fold a sext/zext of a constant build_vector was the root
cause of some pcg bugs affecting vselect expansion on x86-64 with AVX support.

Before this change, the DAGCombiner only knew how to fold a sext/zext/aext of a
ConstantSDNode.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200234 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-27 18:45:30 +00:00
Stepan Dyatkovskiy
9019340120 Additional fix for 200201: due to dependence on bitwidth test was moved to X86 directory.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200202 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-27 09:43:10 +00:00
Juergen Ributzka
943ce55f39 Revert "Revert "Add Constant Hoisting Pass" (r200034)"
This reverts commit r200058 and adds the using directive for
ARMTargetTransformInfo to silence two g++ overload warnings.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200062 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-25 02:02:55 +00:00
Hans Wennborg
503793e834 Revert "Add Constant Hoisting Pass" (r200034)
This commit caused -Woverloaded-virtual warnings. The two new
TargetTransformInfo::getIntImmCost functions were only added to the superclass,
and to the X86 subclass. The other targets were not updated, and the
warning highlighted this by pointing out that e.g. ARMTTI::getIntImmCost was
hiding the two new getIntImmCost variants.

We could pacify the warning by adding "using TargetTransformInfo::getIntImmCost"
to the various subclasses, or turning it off, but I suspect that it's wrong to
leave the functions unimplemnted in those targets. The default implementations
return TCC_Free, which I don't think is right e.g. for ARM.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200058 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-25 01:18:18 +00:00
Juergen Ributzka
96172cb4a4 Add Constant Hoisting Pass
Retry commit r200022 with a fix for the build bot errors. Constant expressions
have (unlike instructions) module scope use lists and therefore may have users
in different functions. The fix is to simply ignore these out-of-function uses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200034 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 20:18:00 +00:00
Lang Hames
a9699d475f Add a testcase for the changes in r199938.
<rdar://problem/15611947>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200027 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 19:00:19 +00:00
Juergen Ributzka
dc6f9b9a4f Revert "Add Constant Hoisting Pass"
This reverts commit r200022 to unbreak the build bots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200024 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 18:40:30 +00:00
Juergen Ributzka
fb282c68b7 Add Constant Hoisting Pass
This pass identifies expensive constants to hoist and coalesces them to
better prepare it for SelectionDAG-based code generation. This works around the
limitations of the basic-block-at-a-time approach.

First it scans all instructions for integer constants and calculates its
cost. If the constant can be folded into the instruction (the cost is
TCC_Free) or the cost is just a simple operation (TCC_BASIC), then we don't
consider it expensive and leave it alone. This is the default behavior and
the default implementation of getIntImmCost will always return TCC_Free.

If the cost is more than TCC_BASIC, then the integer constant can't be folded
into the instruction and it might be beneficial to hoist the constant.
Similar constants are coalesced to reduce register pressure and
materialization code.

When a constant is hoisted, it is also hidden behind a bitcast to force it to
be live-out of the basic block. Otherwise the constant would be just
duplicated and each basic block would have its own copy in the SelectionDAG.
The SelectionDAG recognizes such constants as opaque and doesn't perform
certain transformations on them, which would create a new expensive constant.

This optimization is only applied to integer constants in instructions and
simple (this means not nested) constant cast experessions. For example:
%0 = load i64* inttoptr (i64 big_constant to i64*)

Reviewed by Eric

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200022 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 18:23:08 +00:00
Alp Toker
ae43cab6ba Fix known typos
Sweep the codebase for common typos. Includes some changes to visible function
names that were misspelt.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200018 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 17:20:08 +00:00
Juergen Ributzka
fe08a38a2c [X86] Prevent the creation of redundant ops for sadd and ssub with overflow.
This commit teaches the X86 backend to create the same X86 instructions when it
lowers an sadd/ssub with overflow intrinsic and a conditional branch that uses
that overflow result. This allows SelectionDAG to recognize and remove one of
the redundant operations.

This fixes <rdar://problem/15874016> and <rdar://problem/15661073>.

Reviewed by Nadav

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199976 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 06:47:57 +00:00
Lang Hames
d8f4348cab Replace vfmaddxx213 instructions with their 231-type equivalents in accumulator
loops. Writing back to the accumulator (231-type) allows the coalescer to
eliminate an extra copy.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199933 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-23 20:23:36 +00:00
Elena Demikhovsky
e1a621d84f AVX-512: added VPERM2D VPERM2Q VPERM2PS VPERM2PD instructions,
they give better sequences than VPERMI


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199893 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-23 14:27:26 +00:00
Owen Anderson
9920bd341a Revert r162101 and replace it with a solution that works for targets where the pointer type is illegal.
This is a horrible bit of code.  We're calling a simplification routine *in the middle* of type legalization.  We tell the
simplification routine that it's running after legalization, but some of the types it will encounter will be illegal!  The
fix is only to invoke the simplification if the types in question were legal, so that none of its invariants will be violated.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199847 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-22 22:34:17 +00:00
Quentin Colombet
8b594ba851 Add a testcase for r199430.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199831 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-22 20:11:50 +00:00
Elena Demikhovsky
c75a44cda7 AVX512: combining setcc and zext is wrong on AVX512
because vector compare instruction puts result in mask register.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199798 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-22 12:26:19 +00:00
James Molloy
bb96dfcf4f MachineCopyPropagation has special logic for removing COPY instructions. It will remove plain COPYs using eraseFromParent(), but if the COPY has imp-defs/imp-uses it will convert it to a KILL, to keep the imp-def around.
This actually totally breaks and causes the machine verifier to cry in several cases, one of which being:

%RAX<def> = COPY %RCX<kill>
%ECX<def> = COPY %EAX<kill>, %RAX<imp-use,kill>

These subregister copies are together identified as noops, so are both removed. However, the second one as it has an imp-use gets converted into a kill:

%ECX<def> = KILL %EAX<kill>, %RAX<imp-use,kill>

As the original COPY has been removed, the verifier goes into tears at the use of undefined EAX and RAX.

There are several hacky solutions to this hacky problem (which is all to do with imp-use/def weirdnesses), but the least hacky I've come up with is to *always* remove COPYs by converting to KILLs. KILLs are no-ops to the code generator so the generated code doesn't change (which is why they were partially used in the first place), but using them also keeps the def/use and imp-def/imp-use chains alive:

%RAX<def> = KILL %RCX<kill>
%ECX<def> = KILL %EAX<kill>, %RAX<imp-use,kill>

The patch passes all test cases including the ones that check the removal of MOVs in this circumstance, along with an extra test I added to check subregister behaviour (which made the machine verifier fall over before my patch).

The patch also adds some DEBUG() statements because the file hadn't got any.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199797 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-22 09:12:27 +00:00
Chandler Carruth
182a02a8dc Tweak the spelling of the asserts requirement a bit more. This makes it
match the (reasonably prevelant) usage in Clang's test suite and so
seems more "canonical".

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199767 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-21 22:39:19 +00:00
Andrea Di Biagio
825b93b2df [X86] Teach how to combine a vselect into a movss/movsd
Add target specific rules for combining vselect dag nodes into movss/movsd
when possible.

If the vector type of the vselect dag node in input is either MVT::v4i13 or
MVT::v4f32, then try to fold according to rules:

  1) fold (vselect (build_vector (0, -1, -1, -1)), A, B) -> (movss A, B)
  2) fold (vselect (build_vector (-1, 0, 0, 0)), A, B) -> (movss B, A)

If the vector type of the vselect dag node in input is either MVT::v2i64 or
MVT::v2f64 (and we have SSE2), then try to fold according to rules:

  3) fold (vselect (build_vector (0, -1)), A, B) -> (movsd A, B)
  4) fold (vselect (build_vector (-1, 0)), A, B) -> (movsd B, A)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199683 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-20 19:35:22 +00:00
Hal Finkel
54c251c77f Fix misched-aa-colored.ll to require asserts (trying again)
Perhaps it needs to be in caps.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199661 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-20 14:15:28 +00:00
Hal Finkel
42691ad862 Fix misched-aa-colored.ll to require asserts.
-misched=shuffle is NDEBUG only. Maybe we should change that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199659 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-20 14:09:34 +00:00
Hal Finkel
48f7a2389e Update IR when merging slots in stack coloring
The way that stack coloring updated MMOs when merging stack slots, while
correct, is suboptimal, and is incompatible with the use of AA during
instruction scheduling. The solution, which involves the use of const_cast (and
more importantly, updating the IR from within an MI-level pass), obviously
requires some explanation:

When the stack coloring pass was originally committed, the code in
ScheduleDAGInstrs::buildSchedGraph tracked possible alias sets by using
GetUnderlyingObject, and all load/store and store/store memory control
dependencies where added between SUs at the object level (where only one
object, that returned by GetUnderlyingObject, was used to identify the object
associated with each MMO). When stack coloring merged stack slots, it would
replace MMOs derived from the remapped alloca with the alloca with which the
remapped alloca was being replaced. Because ScheduleDAGInstrs only used single
objects, and tracked alias sets at the object level, this was a fine solution.

In r169744, (Andy and) I updated the code in ScheduleDAGInstrs to use
GetUnderlyingObjects, and track alias sets using, potentially, multiple
underlying objects for each MMO. This was done, primarily, to provide the
ability to look through PHIs, and provide better scheduling for
induction-variable-dependent loads and stores inside loops. At this point, the
MMO-updating code in stack coloring became suboptimal, because it would clear
the MMOs for (i.e. completely pessimize) all instructions for which r169744
might help in scheduling. Updating the IR directly is the simplest fix for this
(and the one with, by far, the least compile-time impact), but others are
possible (we could give each MMO a small vector of potential values, or make
use of a remapping table, constructed from MFI, inside ScheduleDAGInstrs).

Unfortunately, replacing all MMO values derived from the remapped alloca with
the base replacement alloca fundamentally breaks our ability to use AA during
instruction scheduling (which is critical to performance on some targets). The
reason is that the original MMO might have had an offset (either constant or
dynamic) from the base remapped alloca, and that offset is not present in the
updated MMO. One possible way around this would be to use
GetPointerBaseWithConstantOffset, and update not only the MMO's value, but also
its offset based on the original offset. Unfortunately, this solution would
only handle constant offsets, and for safety (because AA is not completely
restricted to deducing relationships with constant offsets), we would need to
clear all MMOs without constant offsets over the entire function. This would be
an even worse pessimization than the current single-object restriction. Any
other solution would involve passing around a vector of remapped allocas, and
teaching AA to use it, introducing additional complexity and overhead into AA.

Instead, when remapping an alloca, we replace all IR uses of that alloca as
well (optionally inserting a bitcast as necessary). This is even more efficient
that the old MMO-updating code in the stack coloring pass (because it removes
the need to call GetUnderlyingObject on all MMO values), removes the
single-object pessimization in the default configuration, and enables the
correct use of AA during instruction scheduling (all without any additional
overhead).

LLVM now no longer miscompiles itself on x86_64 when using -enable-misched
-enable-aa-sched-mi -misched-bottomup=0 -misched-topdown=0 -misched=shuffle!
Fixed PR18497.

Because the alloca replacement is now done at the IR level, unless the MMO
directly refers to the remapped alloca, the change cannot be seen at the MI
level. As a result, there is no good way to fix test/CodeGen/X86/pr14090.ll.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199658 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-20 14:03:16 +00:00