Commit Graph

907 Commits

Author SHA1 Message Date
Ulrich Weigand 8a9c531e9a [PowerPC] Load BlockAddress values from the TOC in 64-bit SVR4 code
Since block address values can be larger than 2GB in 64-bit code, they
cannot be loaded simply using an @l / @ha pair, but instead must be
loaded from the TOC, just like GlobalAddress, ConstantPool, and
JumpTable values are.

The commit also fixes a bug in PPCLinuxAsmPrinter::doFinalization where
temporary labels could not be used as TOC values, since code would
attempt (and fail) to use GetOrCreateSymbol to create a symbol of the
same name as the temporary label.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220959 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-31 10:33:14 +00:00
Sanjay Patel a46f06efe2 Use rsqrt (X86) to speed up reciprocal square root calcs
This is a first step for generating SSE rsqrt instructions for
reciprocal square root calcs when fast-math is allowed.

For now, be conservative and only enable this for AMD btver2
where performance improves significantly - for example, 29%
on llvm/projects/test-suite/SingleSource/Benchmarks/BenchmarkGame/n-body.c
(if we convert the data type to single-precision float).

This patch adds a two constant version of the Newton-Raphson
refinement algorithm to DAGCombiner that can be selected by any target
via a parameter returned by getRsqrtEstimate()..

See PR20900 for more details:
http://llvm.org/bugs/show_bug.cgi?id=20900

Differential Revision: http://reviews.llvm.org/D5658



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220570 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-24 17:02:16 +00:00
Bill Schmidt 55321cd8a7 [PATCH] Support select-cc for VSFRC when VSX is enabled
A previous patch enabled SELECT_VSRC and SELECT_CC_VSRC for VSX to
handle <2 x double> cases.  This patch adds SELECT_VSFRC and
SELECT_CC_VSFRC to allow use of all 64 vector-scalar registers for the
f64 type when VSX is enabled.  The changes are analogous to those in
the previous patch.  I've added a new variant to vsx.ll to test the
code generation.

(I also cleaned up a little formatting in PPCInstrVSX.td from the
previous patch.)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220395 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-22 16:58:20 +00:00
Bill Schmidt 013cbf2f1a [PowerPC] Support select-cc for VSX
The tests test/CodeGen/Generic/select-cc.ll and
test/CodeGen/PowerPC/select-cc.ll both fail with VSX enabled.  The
problem is that the lowering logic for the SELECT and SELECT_CC
operations doesn't currently support the VSX registers.  This patch
fixes that.

In lib/Target/PowerPC/PPCInstrInfo.td, we have pseudos to handle this
for other register classes.  Similar pseudos are added in
PPCInstrVSX.td (they must be there, because the "vsrc" register class
definition appears there) for the VSRC register class.  The
SELECT_VSRC pseudo is then used in pattern matching for SELECT_CC.

The rest of the patch just adds logic for SELECT_VSRC wherever similar
logic appears for SELECT_VRRC.

There are no new test cases because the existing tests above test
this, along with a variant in test/CodeGen/PowerPC/vsx.ll.

After discussion with Hal, a future patch will add similar _VSFRC
variants to override f64 type handling (currently using F8RC).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220385 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-22 13:13:40 +00:00
Bill Schmidt b76f5ba103 [PowerPC] Enable use of lxvw4x/stxvw4x in VSX code generation
Currently the VSX support enables use of lxvd2x and stxvd2x for 2x64
types, but does not yet use lxvw4x and stxvw4x for 4x32 types.  This
patch adds that support.

As with lxvd2x/stxvd2x, this involves straightforward overriding of
the patterns normally recognized for lvx/stvx, with preference given
to the VSX patterns when VSX is enabled.

In addition, the logic for permitting misaligned memory accesses is
modified so that v4r32 and v4i32 are treated the same as v2f64 and
v2i64 when VSX is enabled.  Finally, the DAG generation for unaligned
loads is changed to just use a normal LOAD (which will become lxvw4x)
on P8 and later hardware, where unaligned loads are preferred over
lvsl/lvx/lvx/vperm.

A number of tests now generate the VSX loads/stores instead of
lvx/stvx, so this patch adds VSX variants to those tests.  I've also
added <4 x float> tests to the vsx.ll test case, and created a
vsx-p8.ll test case to be used for testing code generation for the
P8Vector feature.  For now, that simply tests the unaligned load/store
behavior.

This has been tested along with a temporary patch to enable the VSX
and P8Vector features, with no new regressions encountered with or
without the temporary patch applied.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220047 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-17 15:13:38 +00:00
Robin Morisset 2b1874cbd4 [Power] Improve the expansion of atomic loads/stores
Summary:
Atomic loads and store of up to the native size (32 bits, or 64 for PPC64)
can be lowered to a simple load or store instruction (as the synchronization
is already handled by AtomicExpand, and the atomicity is guaranteed thanks to
the alignment requirements of atomic accesses). This is exactly what this patch
does. Previously, these were implemented by complex
load-linked/store-conditional loops.. an obvious performance problem.

For example, this patch turns
```
define void @store_i8_unordered(i8* %mem) {
  store atomic i8 42, i8* %mem unordered, align 1
  ret void
}
```
from
```
_store_i8_unordered:                    ; @store_i8_unordered
; BB#0:
    rlwinm r2, r3, 3, 27, 28
    li r4, 42
    xori r5, r2, 24
    rlwinm r2, r3, 0, 0, 29
    li r3, 255
    slw r4, r4, r5
    slw r3, r3, r5
    and r4, r4, r3
LBB4_1:                                 ; =>This Inner Loop Header: Depth=1
    lwarx r5, 0, r2
    andc r5, r5, r3
    or r5, r4, r5
    stwcx. r5, 0, r2
    bne cr0, LBB4_1
; BB#2:
    blr
```
into
```
_store_i8_unordered:                    ; @store_i8_unordered
; BB#0:
    li r2, 42
    stb r2, 0(r3)
    blr

```
which looks like a pretty clear win to me.

Test Plan:
fixed the tests + new test for indexed accesses + make check-all

Reviewers: jfb, wschmidt, hfinkel

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5587

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218922 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 22:27:07 +00:00
Eric Christopher 300743f74a constify the TargetMachine argument used in the subtarget and
lowering constructors.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218832 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 21:36:28 +00:00
Sanjay Patel cafc85bf1e Split the estimate() interface into separate functions for each type. NFC.
It was hacky to use an opcode as a switch because it won't always match
(rsqrte != sqrte), and it looks like we'll need to add more special casing
per arch than I had hoped for. Eg, x86 will prefer a different NR estimate
implementation. ARM will want to use it's 'step' instructions. There also
don't appear to be any new estimate instructions in any arch in a long,
long time. Altivec vloge and vexpte may have been the first and last in
that field...



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218698 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-30 20:28:48 +00:00
Sanjay Patel 676af35b38 Refactor reciprocal and reciprocal square root estimate into target-independent functions (part 2).
This is purely refactoring. No functional changes intended. PowerPC is the only target
that is currently using this interface.

The ultimate goal is to allow targets other than PowerPC (certainly X86 and Aarch64) to turn this:

z = y / sqrt(x)

into:

z = y * rsqrte(x)

And:

z = y / x

into:

z = y * rcpe(x)

using whatever HW magic they can use. See http://llvm.org/bugs/show_bug.cgi?id=20900 .

There is one hook in TargetLowering to get the target-specific opcode for an estimate instruction
along with the number of refinement steps needed to make the estimate usable.

Differential Revision: http://reviews.llvm.org/D5484



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218553 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 23:01:47 +00:00
Robin Morisset 58bca6e8ec [Power] Use AtomicExpandPass for fence insertion, and use lwsync where appropriate
Summary:
This patch makes use of AtomicExpandPass in Power for inserting fences around
atomic as part of an effort to remove fence insertion from SelectionDAGBuilder.
As a big bonus, it lets us use sync 1 (lightweight sync, often used by the mnemonic
lwsync) instead of sync 0 (heavyweight sync) in many cases.

I also added a test, as there was no test for the barriers emitted by the Power
backend for atomic loads and stores.

Test Plan: new test + make check-all

Reviewers: jfb

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5180

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218331 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-23 20:46:49 +00:00
Sanjay Patel 3e05b40fd0 Refactor reciprocal square root estimate into target-independent function; NFC.
This is purely a plumbing patch. No functional changes intended.

The ultimate goal is to allow targets other than PowerPC (certainly X86 and Aarch64) to turn this:

z = y / sqrt(x)

into:

z = y * rsqrte(x)

using whatever HW magic they can use. See http://llvm.org/bugs/show_bug.cgi?id=20900 .

The first step is to add a target hook for RSQRTE, take the already target-independent code selfishly hoarded by PPC, and put it into DAGCombiner.

Next steps:

    The code in DAGCombiner::BuildRSQRTE() should be refactored further; tests that exercise that logic need to be added.
    Logic in PPCTargetLowering::BuildRSQRTE() should be hoisted into DAGCombiner.
    X86 and AArch64 overrides for TargetLowering.BuildRSQRTE() should be added.

Differential Revision: http://reviews.llvm.org/D5425



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218219 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-21 15:19:15 +00:00
Hal Finkel c404e8208c Optionally enable more-aggressive FMA formation in DAGCombine
The heuristic used by DAGCombine to form FMAs checks that the FMUL has only one
use, but this is overly-conservative on some systems. Specifically, if the FMA
and the FADD have the same latency (and the FMA does not compete for resources
with the FMUL any more than the FADD does), there is no need for the
restriction, and furthermore, forming the FMA leaving the FMUL can still allow
for higher overall throughput and decreased critical-path length.

Here we add a new TLI callback, enableAggressiveFMAFusion, false by default, to
elide the hasOneUse check. This is enabled for PowerPC by default, as most
PowerPC systems will benefit.

Patch by Olivier Sallenave, thanks!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218120 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-19 11:42:56 +00:00
Craig Topper c4e394a333 Use cast to MVT instead of EVT on a couple calls to getSizeInBits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217473 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-10 04:51:36 +00:00
Eric Christopher d5dd8ce2a5 Reinstate "Nuke the old JIT."
Approved by Jim Grosbach, Lang Hames, Rafael Espindola.

This reinstates commits r215111, 215115, 215116, 215117, 215136.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216982 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-02 22:28:02 +00:00
Sanjay Patel d1a09c47d2 name change: isPow2DivCheap -> isPow2SDivCheap
isPow2DivCheap

That name doesn't specify signed or unsigned.

Lazy as I am, I eventually read the function and variable comments. It turns out that this is strictly about signed div. But I discovered that the comments are wrong:

   srl/add/sra

is not the general sequence for signed integer division by power-of-2. We need one more 'sra':

   sra/srl/add/sra

That's the sequence produced in DAGCombiner. The first 'sra' may be removed when dividing by exactly '2', but that's a special case.

This patch corrects the comments, changes the name of the flag bit, and changes the name of the accessor methods.

No functional change intended.

Differential Revision: http://reviews.llvm.org/D5010


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216237 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-21 22:31:48 +00:00
Hal Finkel 5dc48ac04a [PowerPC] Mark fixed-offset byvals as pointed-to by IR values
A byval object, even if allocated at a fixed offset (prescribed by the ABI) is
pointed to by IR values. Most fixed-offset stack objects are not pointed-to by
IR values, so the default is to assume this is not possible. However, we need
to override the default in this case (instruction scheduling can cause
miscompiles otherwise).

Fixes PR20280.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215795 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-16 00:17:05 +00:00
Hal Finkel bdd8b6bfb9 [PowerPC] Darwin byval arguments are not immutable
On PPC/Darwin, byval arguments occur at fixed stack offsets in the callee's
frame, but are not immutable -- the pointer value is directly available to the
higher-level code as the address of the argument, and the value of the byval
argument can be modified at the IR level.

This is necessary, but not sufficient, to fix PR20280. When PR20280 is fixed in
a follow-up commit, its test case will cover this change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215793 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-16 00:16:29 +00:00
Hal Finkel e693d3c558 [PowerPC] Implement PPCTargetLowering::getTgtMemIntrinsic
This implements PPCTargetLowering::getTgtMemIntrinsic for Altivec load/store
intrinsics. As with the construction of the MachineMemOperands for the
intrinsic calls used for unaligned load/store lowering, the only slight
complication is that we need to represent a larger memory range than the
loaded/stored value-type size (because the address is rounded down to an
aligned address, and we need to conservatively represent the entire possible
range of the actual access). This required adding an extra size field to
TargetLowering::IntrinsicInfo, and this was done in a way that required no
modifications to other targets (the size defaults to the store size of the
provided memory data type).

This fixes test/CodeGen/PowerPC/unal-altivec-wint.ll (so it can be un-XFAILed).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215512 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-13 01:15:40 +00:00
Joerg Sonnenberger 6f3e49e03c Add low-level option for avoiding float stores from va_start until
soft-float is properly supported.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215221 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-08 16:46:10 +00:00
Eric Christopher aa5b9c0f6f Temporarily Revert "Nuke the old JIT." as it's not quite ready to
be deleted. This will be reapplied as soon as possible and before
the 3.6 branch date at any rate.

Approved by Jim Grosbach, Lang Hames, Rafael Espindola.

This reverts commits r215111, 215115, 215116, 215117, 215136.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215154 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 22:02:54 +00:00
Rafael Espindola 875710a2fd Nuke the old JIT.
I am sure we will be finding bits and pieces of dead code for years to
come, but this is a good start.

Thanks to Lang Hames for making MCJIT a good replacement!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215111 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 14:21:18 +00:00
Eric Christopher 41612a9b85 Remove the target machine from CCState. Previously it was only used
to get the subtarget and that's accessible from the MachineFunction
now. This helps clear the way for smaller changes where we getting
a subtarget will require passing in a MachineFunction/Function as
well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214988 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 18:45:26 +00:00
Bill Schmidt bb639a1f96 [PowerPC] Swap arguments and adjust shift count for vsldoi on little endian
Commits r213915 and r214718 fix recognition of shuffle masks for vmrg*
and vpku*um instructions for a little-endian target, by swapping the
input arguments.  The vsldoi instruction requires similar treatment,
and also needs its shift count adjusted for little endian.

Reviewed by Ulrich Weigand.

This is a bug fix candidate for release 3.5 (and hopefully the last of
those for PowerPC).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214923 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-05 20:47:25 +00:00
Eric Christopher 6035518e3b Have MachineFunction cache a pointer to the subtarget to make lookups
shorter/easier and have the DAG use that to do the same lookup. This
can be used in the future for TargetMachine based caching lookups from
the MachineFunction easily.

Update the MIPS subtarget switching machinery to update this pointer
at the same time it runs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214838 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-05 02:39:49 +00:00
Bill Schmidt 84fef1f55d [PPC64LE] Fix wrong IR for vec_sld and vec_vsldoi
My original LE implementation of the vsldoi instruction, with its
altivec.h interfaces vec_sld and vec_vsldoi, produces incorrect
shufflevector operations in the LLVM IR.  Correct code is generated
because the back end handles the incorrect shufflevector in a
consistent manner.

This patch and a companion patch for Clang correct this problem by
removing the fixup from altivec.h and the corresponding fixup from the
PowerPC back end.  Several test cases are also modified to reflect the
now-correct LLVM IR.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214800 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-04 23:21:01 +00:00