In constant folding stage, "TRUNC" can't handle vector data type.

llvm-svn: 216149

llvm-svn: 216147

advanced copy optimization.

This is the final step patch toward transforming:
udiv    r0, r0, r2
udiv    r1, r1, r3
vmov.32 d16[0], r0
vmov.32 d16[1], r1
vmov    r0, r1, d16
bx      lr

into:
udiv    r0, r0, r2
udiv    r1, r1, r3
bx      lr

Indeed, thanks to this patch, this optimization is able to look through
vmov.32 d16[0], r0
vmov.32 d16[1], r1

and is able to rewrite the following sequence:
vmov.32 d16[0], r0
vmov.32 d16[1], r1
vmov    r0, r1, d16

into simple generic GPR copies that the coalescer managed to remove.

<rdar://problem/12702965>

llvm-svn: 216144

target hook.

This patch teaches the compiler that:
dX = VSETLNi32 dY, rZ, imm
is the same as:
dX = INSERT_SUBREG dY, rZ, translateImmToSubIdx(imm)

<rdar://problem/12702965>

llvm-svn: 216143

Only for Cortex-A57 and Cyclone for now, where it has shown wins.

llvm-svn: 216141

If we have a scalar reduction, we can increase the critical path length if the loop we're unrolling is inside another loop. Limit, by default to 2, so the critical path only gets increased by one reduction operation.

llvm-svn: 216140

This patch adds a new property: isInsertSubreg and the related target hooks:
TargetIntrInfo::getInsertSubregInputs and
TargetInstrInfo::getInsertSubregLikeInputs to specify that a target specific
instruction is a (kind of) INSERT_SUBREG.

The approach is similar to r215394.

<rdar://problem/12702965>

llvm-svn: 216139

On pre-v6 hardware, 'MOV lo, lo' gives undefined results, so such copies need to
be avoided. This patch trades simplicity for implementation time at the expense
of performance... As they say: correctness first, then performance.

See http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075998.html for a few
ideas on how to make this better.

llvm-svn: 216138

llvm-svn: 216137

advanced copy optimization.

This patch is a step toward transforming:
udiv	r0, r0, r2
udiv	r1, r1, r3
vmov.32	d16[0], r0
vmov.32	d16[1], r1
vmov	r0, r1, d16
bx	lr

into:
udiv	r0, r0, r2
udiv	r1, r1, r3
bx	lr

Indeed, thanks to this patch, this optimization is able to look through
vmov r0, r1, d16
but it does not understand yet
vmov.32 d16[0], r0
vmov.32 d16[1], r1

Comming patches will fix that and update the related test case.

<rdar://problem/12702965>

llvm-svn: 216136

New InstCombine pattern: (icmp ult/ule (A + C1), C3) | (icmp ult/ule (A + C2), C3)  to (icmp ult/ule ((A & ~(C1 ^ C2)) + max(C1, C2)), C3) under certain condition

llvm-svn: 216135

It makes no sense and can hide bugs. In particular, it lead
to left shift by 64 bits, which is an undefined behavior,
properly reported by UBSan.

llvm-svn: 216134

target hook.

This patch teaches the compiler that:
rX, rY = VMOVRRD dZ
is the same as:
rX = EXTRACT_SUBREG dZ, ssub_0
rY = EXTRACT_SUBREG dZ, ssub_1

<rdar://problem/12702965>

llvm-svn: 216132

This bug is reported by UBSan.

llvm-svn: 216131

This patch adds a new property: isExtractSubreg and the related target hooks:
TargetIntrInfo::getExtractSubregInputs and
TargetInstrInfo::getExtractSubregLikeInputs to specify that a target specific
instruction is a (kind of) EXTRACT_SUBREG.

The approach is similar to r215394.

<rdar://problem/12702965>

llvm-svn: 216130

Store TargetSelectionDAGInfo as a pointer instead of a reference:
getSelectionDAGInfo() may not be implemented for certain backends
(e.g. it's not currently implemented for R600).

This bug is reported by UBSan.

llvm-svn: 216129

This bug is reported by UBSan.

llvm-svn: 216125

llvm-svn: 216124

Fix for PR20648 - http://llvm.org/bugs/show_bug.cgi?id=20648

This patch checks the operands of a vselect to see if all values are constants.
If yes, bail out of any further attempts to create a blend or shuffle because
SelectionDAGLegalize knows how to turn this kind of vselect into a single load.

This already happens for machines without SSE4.1, so the added checks just send
more targets down that path.

Differential Revision: http://reviews.llvm.org/D4934

llvm-svn: 216121

llvm-svn: 216120

The goal of the patch is to implement section 3.2.3 of the AMD64 ABI
correctly.  The controlling sentence is, "The size of each argument gets
rounded up to eightbytes.  Therefore the stack will always be eightbyte
aligned." The equivalent sentence in the i386 ABI page 37 says, "At all
times, the stack pointer should point to a word-aligned area."  For both
architectures, the stack pointer is not being rounded up to the nearest
eightbyte or word between the last normal argument and the first
variadic argument.

Patch by Thomas Jablin!

llvm-svn: 216119

Both MachineLoopInfo and MachineDominatorTree may be null in ScheduleDAGMI
constructor call. It is undefined behavior to take references to these values.

This bug is reported by UBSan.

llvm-svn: 216118

Summary: This fixes http://llvm.org/bugs/show_bug.cgi?id=19530.
The problem is that X86ISelLowering erroneously thought the third call
was eligible for tail call elimination.
It would have been if it's return value was actually the one returned
by the calling function, but here that is not the case and
additional values are being returned.

Test Plan: Test case from the original bug report is included.

Reviewers: rafael

Reviewed By: rafael

Subscribers: rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D4968

llvm-svn: 216117

This bug is reported by UBSan.

llvm-svn: 216116

In PR20308 ( http://llvm.org/bugs/show_bug.cgi?id=20308 ), the critical-anti-dependency breaker
caused a miscompile because it broke a WAR hazard using a register that it thinks is available
based on info from a kill inst. Until PR18663 is solved, we shouldn't use any def/use info from
a kill because they are really just nops.

This patch adds guard checks for kills around calls to ScanInstruction() where the DefIndices
array is set. For good measure, add an assert in ScanInstruction() so we don't hit this bug again.

The test case is a reduced version of the code from the bug report.

Differential Revision: http://reviews.llvm.org/D4977

llvm-svn: 216114

the isRegSequence property.

This is a follow-up of r215394 and r215404, which respectively introduces the
isRegSequence property and uses it for ARM.

Thanks to the property introduced by the previous commits, this patch is able
to optimize the following sequence:
vmov	d0, r2, r3
vmov	d1, r0, r1
vmov	r0, s0
vmov	r1, s2
udiv	r0, r1, r0
vmov	r1, s1
vmov	r2, s3
udiv	r1, r2, r1
vmov.32	d16[0], r0
vmov.32	d16[1], r1
vmov	r0, r1, d16
bx	lr

into:
udiv	r0, r0, r2
udiv	r1, r1, r3
vmov.32	d16[0], r0
vmov.32	d16[1], r1
vmov	r0, r1, d16
bx	lr

This patch refactors how the copy optimizations are done in the peephole
optimizer. Prior to this patch, we had one copy-related optimization that
replaced a copy or bitcast by a generic, more suitable (in terms of register
file), copy.

With this patch, the peephole optimizer features two copy-related optimizations:
1. One for rewriting generic copies to generic copies:
PeepholeOptimizer::optimizeCoalescableCopy.
2. One for replacing non-generic copies with generic copies:
PeepholeOptimizer::optimizeUncoalescableCopy.

The goals of these two optimizations are slightly different: one rewrite the
operand of the instruction (#1), the other kills off the non-generic instruction
and replace it by a (sequence of) generic instruction(s).

Both optimizations rely on the ValueTracker introduced in r212100.

The ValueTracker has been refactored to use the information from the
TargetInstrInfo for non-generic instruction. As part of the refactoring, we
switched the tracking from the index of the definition to the actual register
(virtual or physical). This one change is to provide better consistency with
register related APIs and to ease the use of the TargetInstrInfo.

Moreover, this patch introduces a new helper class CopyRewriter used to ease the
rewriting of generic copies (i.e., #1).

Finally, this patch adds a dead code elimination pass right after the peephole
optimizer to get rid of dead code that may appear after rewriting.

This is related to <rdar://problem/12702965>.

Review: http://reviews.llvm.org/D4874
llvm-svn: 216088

I added wrapping to the CFGPrinter a while back so the -view-cfg
output is actually viewable. I've since enountered very long mangled
names with the same problem, so I'm slightly tweaking this code to
work in that case.

llvm-svn: 216087

llvm-svn: 216086

This fixes a bug I introduced in a previous commit (r216033). Sign-/Zero-
extension from i1 cannot be folded into the ADDS/SUBS instructions. Instead both
operands have to be sign-/zero-extended with separate instructions.

Related to <rdar://problem/17913111>.

llvm-svn: 216073

llvm-svn: 216071

how this affects the numbering of unnamed temporaries.

llvm-svn: 216070

llvm-svn: 216068

Silencing an MSVC C4334 warning ('<<' : result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)). NFC.

llvm-svn: 216067

legalization stage. With those two optimizations, fewer signed/zero extension
instructions can be inserted, and then we can expose more opportunities to
Machine CSE pass in back-end.

llvm-svn: 216066

Summary:
Fixes http://llvm.org/bugs/show_bug.cgi?id=20016 reproducible on new
lea-5.ll case.
Also use RSP/RBP for x32 lea to save 1 byte used for 0x67 prefix in
ESP/EBP case.

Test Plan: lea tests modified to include x32/nacl and new test added

Reviewers: nadav, dschuff, t.p.northover

Subscribers: llvm-commits, zinovy.nis

Differential Revision: http://reviews.llvm.org/D4929

llvm-svn: 216065

LLVM generates illegal `rbit r0, #352` instruction for rbit intrinsic.
According to ARM ARM, rbit only takes register as argument, not immediate.
The correct instruction should be rbit <Rd>, <Rm>.

The bug was originally introduced in r211057.

Differential Revision: http://reviews.llvm.org/D4980

llvm-svn: 216064

llvm-svn: 216048

llvm-svn: 216047

We can prove that a 'sub' can be a 'sub nuw' if the left-hand side is
negative and the right-hand side is non-negative.

llvm-svn: 216045

Fix an off by 1 bug that prevented SmallPtrSet from using all of its 'small' capacity. Then fix the early return in the move constructor that prevented 'small' moves from clearing the NumElements in the moved from object. The directed test missed this because it was always testing large moves due to the off by 1 bug.

llvm-svn: 216044