Commit Graph

7145 Commits

Author SHA1 Message Date
Hans Wennborg
1008467523 Merging r243500: (conflicts resolved manually since the branch doesn't have r243293)
------------------------------------------------------------------------
r243500 | spatel | 2015-07-28 16:28:22 -0700 (Tue, 28 Jul 2015) | 16 lines

ignore duplicate divisor uses when transforming into reciprocal multiplies (PR24141)

PR24141: https://llvm.org/bugs/show_bug.cgi?id=24141
contains a test case where we have duplicate entries in a node's uses() list.

After r241826, we use CombineTo() to delete dead nodes when combining the uses into
reciprocal multiplies, but this fails if we encounter the just-deleted node again in
the list.

The solution in this patch is to not add duplicate entries to the list of users that
we will subsequently iterate over. For the test case, this avoids triggering the
combine divisors logic entirely because there really is only one user of the divisor.

Differential Revision: http://reviews.llvm.org/D11345
------------------------------------------------------------------------


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_37@243524 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-29 15:38:37 +00:00
Pete Cooper
ba77f37392 Add allnodes() iterator range to SelectionDAG. NFC.
SelectionDAG already had begin/end methods for iterating over all
the nodes, but didn't define an iterator_range for us in foreach
loops.

This adds such a method and uses it in some of the eligible places
throughout the backends.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242212 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 22:10:54 +00:00
Pete Cooper
f1c70f9279 Constify parameters in SelectionDAG methods. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242210 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 21:54:52 +00:00
Pete Cooper
ec664779b3 Remove unnecessary .getNode() in SelectionDAG. NFC.
The simplify_type specialisation allows us to cast directly from
SDValue to an SDNode* subclass so we don't need to pass a SDNode*
to cast<>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242209 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 21:54:48 +00:00
Pete Cooper
6e6119a92e Use more foreach loops in SelectionDAG. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242208 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 21:54:45 +00:00
Matthias Braun
21910d8bd5 Revert "LegalizeDAG: Fix and improve FCOPYSIGN/FABS legalization"
Accidental commit, needs review first.

This reverts commit r242107.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242108 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 02:09:57 +00:00
Matthias Braun
2a46e4c020 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242107 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 02:08:26 +00:00
James Y Knight
af8cf90e2f Fix handling of the 'n' asm constraint with invalid operands.
It had accidently accepted a symbol+offset value (and emitted
incorrect code for it, keeping only the offset part) instead of
properly reporting the constraint as invalid.

Differential Revision: http://reviews.llvm.org/D11039

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242040 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 16:36:22 +00:00
Matt Arsenault
ee6d5d1c9e DAGCombiner: Assume invariant load cannot alias a store
The motivation is to allow GatherAllAliases / FindBetterChain
to not give up on dependent loads of a pointer from constant memory.

This is important for AMDGPU, because most loads are pointers
derived from a load of a kernel argument from constant memory.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241948 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-10 22:17:40 +00:00
Fiona Glaser
b0a2d8c5a5 ComputeKnownBits: be a bit smarter about ADDs
If our two inputs have known top-zero bit counts M and N, we trivially
know that the output cannot have any bits set in the top (min(M, N)-1)
bits, since nothing could carry past that point.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241927 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-10 18:29:02 +00:00
David Majnemer
eddf9e2057 Revert the new EH instructions
This reverts commits r241888-r241891, I didn't mean to commit them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241893 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-10 07:15:17 +00:00
David Majnemer
751c4be705 New EH representation for MSVC compatibility
Summary:
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support.  Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.

Reviewers: rnk, JosephTremoulet, reames, nlewycky, rjmccall

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11041

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241888 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-10 07:00:44 +00:00
Reid Kleckner
5574399e37 Remove dead code from old 64-bit SEH lowering
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241829 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 17:46:39 +00:00
Pat Gavlin
db5a82b861 Allow {e,r}bp as the target of {read,write}_register.
This patch allows the read_register and write_register intrinsics to
read/write the RBP/EBP registers on X86 iff the targeted register is
the frame pointer for the containing function.

Differential Revision: http://reviews.llvm.org/D10977

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241827 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 17:40:29 +00:00
Sanjay Patel
dc219dddde fix an invisible bug when combining repeated FP divisors
This patch fixes bugs that were exposed by the addition of fast-math-flags in the DAG:
r237046 ( http://reviews.llvm.org/rL237046 ):

1. When replacing a division node, it's not enough to RAUW.
   We should call CombineTo() to delete dead nodes and combine again.
2. Because we are changing the DAG, we can't return an empty SDValue
   after the transform. As the code comments say:

    Visitation implementation - Implement dag node combining for different node types.
    The semantics are as follows: Return Value:
      SDValue.getNode() == 0 - No change was made
      SDValue.getNode() == N - N was replaced, is dead and has been handled.
      otherwise - N should be replaced by the returned Operand.

The new test case shows no difference with or without this patch, but it will crash if
we re-apply r237046 or enable FMF via the current -enable-fmf-dag cl::opt.

Differential Revision: http://reviews.llvm.org/D9893



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241826 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 17:28:37 +00:00
Mehdi Amini
cdc323b2b7 Re-instate the EVT parameter to getScalarShiftAmountTy() for OOT user
A documentation for this function would be nice by the way.

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241807 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 15:12:23 +00:00
Pawel Bylica
dbbfabaf01 Reapply fixed r241790: Fix shift legalization and lowering for big constants.
Summary: If shift amount is a constant value > 64 bit it is handled incorrectly during type legalization and X86 lowering. This patch the type of shift amount argument in function DAGTypeLegalizer::ExpandShiftByConstant from unsigned to APInt.

Reviewers: nadav, majnemer, sanjoy, RKSimon

Subscribers: RKSimon, llvm-commits

Differential Revision: http://reviews.llvm.org/D10767

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241806 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 14:58:04 +00:00
Pawel Bylica
b0205f5937 Revert r241790: Fix shift legalization and lowering for big constants.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241792 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 09:50:54 +00:00
Pawel Bylica
71386b0e04 Fix shift legalization and lowering for big constants.
Summary: If shift amount is a constant value > 64 bit it is handled incorrectly during type legalization and X86 lowering. This patch the type of shift amount argument in function DAGTypeLegalizer::ExpandShiftByConstant from unsigned to APInt.

Reviewers: nadav, majnemer, sanjoy, RKSimon

Subscribers: RKSimon, llvm-commits

Differential Revision: http://reviews.llvm.org/D10767

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241790 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 08:01:36 +00:00
Elena Demikhovsky
43afab3bdb Extended syntax of vector version of getelementptr instruction.
The justification of this change is here: http://lists.cs.uiuc.edu/pipermail/llvmdev/2015-March/082989.html

According to the current GEP syntax, vector GEP requires that each index must be a vector with the same number of elements.

%A = getelementptr i8, <4 x i8*> %ptrs, <4 x i64> %offsets

In this implementation I let each index be or vector or scalar. All vector indices must have the same number of elements. The scalar value will mean the splat vector value.

(1) %A = getelementptr i8, i8* %ptr, <4 x i64> %offsets
or
(2) %A = getelementptr i8, <4 x i8*> %ptrs, i64 %offset

In all cases the %A type is <4 x i8*>

In the case (2) we add the same offset to all pointers.

The case (1) covers C[B[i]] case, when we have the same base C and different offsets B[i].

The documentation is updated.

http://reviews.llvm.org/D10496




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241788 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 07:42:48 +00:00
Mehdi Amini
dc4dccabf3 Remove getDataLayout() from TargetSelectionDAGInfo (had no users)
Summary:
Remove empty subclass in the process.

This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren, ted

Differential Revision: http://reviews.llvm.org/D11045

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241780 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:10:08 +00:00
Mehdi Amini
691b2ff11e Remove getDataLayout() from TargetLowering
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: yaron.keren, rafael, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D11042

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241779 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:52 +00:00
Mehdi Amini
0e496c884c Make isLegalAddressingMode() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11040

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241778 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:40 +00:00
Mehdi Amini
027a9f4561 Make getByValTypeAlignment() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: yaron.keren, rafael, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D11038

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241777 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:28 +00:00
Mehdi Amini
29a2d864d4 Make TargetLowering::getShiftAmountTy() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11037

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241776 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:20 +00:00
Mehdi Amini
f29cc18dcb Make TargetLowering::getPointerTy() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, ted, yaron.keren, rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D11028

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241775 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:04 +00:00
Mehdi Amini
103bdfccee Redirect DataLayout from TargetMachine to Module in ComputeValueVTs()
Summary:
Avoid using the TargetMachine owned DataLayout and use the Module owned
one instead. This requires passing the DataLayout up the stack to
ComputeValueVTs().

This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, yaron.keren, rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D11019

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241773 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 01:57:34 +00:00
Sanjay Patel
ea64a51108 early exits -> less indenting; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241716 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-08 19:32:39 +00:00
Mehdi Amini
7bcdaa6978 Remove IsLittleEndian from TargetLowering and redirect to DataLayout
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11017

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241655 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-08 01:00:38 +00:00
Reid Kleckner
39ee70ca76 [WinEH] Make llvm.x86.seh.restoreframe work for stack realignment prologues
The incoming EBP value points to the end of a local stack allocation, so
we can use that to restore ESI, the base pointer. Once we do that, we
can use local stack allocations. If we know we need stack realignment,
spill the original frame pointer in the prologue and reload it after
restoring ESI.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241648 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-07 23:45:58 +00:00
Reid Kleckner
8f32e5f0d6 Rename llvm.frameescape and llvm.framerecover to localescape and localrecover
Summary:
Initially, these intrinsics seemed like part of a family of "frame"
related intrinsics, but now I think that's more confusing than helpful.
Initially, the LangRef specified that this would create a new kind of
allocation that would be allocated at a fixed offset from the frame
pointer (EBP/RBP). We ended up dropping that design, and leaving the
stack frame layout alone.

These intrinsics are really about sharing local stack allocations, not
frame pointers. I intend to go further and add an `llvm.localaddress()`
intrinsic that returns whatever register (EBP, ESI, ESP, RBX) is being
used to address locals, which should not be confused with the frame
pointer.

Naming suggestions at this point are welcome, I'm happy to re-run sed.

Reviewers: majnemer, nicholas

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11011

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241633 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-07 22:25:32 +00:00
Mehdi Amini
298a718c94 Redirect DataLayout from TargetMachine to Module in SelectionDAG
Summary:
SelectionDAG itself is not invoking directly the DataLayout in the
TargetMachine, but the "TargetLowering" class is still using it. I'll
address it in a following commit.

This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11000

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241618 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-07 19:07:19 +00:00
Mehdi Amini
26a2a4b4ed Redirect DataLayout from TargetMachine to Module in FastISel
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10985

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241613 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-07 18:39:02 +00:00
Peter Collingbourne
ce2b45bd7d IR: Do not consider available_externally linkage to be linker-weak.
From the linker's perspective, an available_externally global is equivalent
to an external declaration (per isDeclarationForLinker()), so it is incorrect
to consider it to be a weak definition.

Also clean up some logic in the dead argument elimination pass and clarify
its comments to better explain how its behavior depends on linkage,
introduce GlobalValue::isStrongDefinitionForLinker() and start using
it throughout the optimizers and backend.

Differential Revision: http://reviews.llvm.org/D10941

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241413 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-05 20:52:35 +00:00
Benjamin Kramer
54b3b4c15e [TargetLowering] StringRefize asm constraint getters.
There is some functional change here because it changes target code from
atoi(3) to StringRef::getAsInteger which has error checking. For valid
constraints there should be no difference.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241411 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-05 19:29:18 +00:00
Nadav Rotem
6890be345e Fix an overly aggressive assertion in getCopyFromPartsVector.
The assertion in getCopyFromPartsVector assumed that the vector 'part' must
match the type of argument (arguments are potentially split into multiple
parts). However, in some cases the targets return a 'part' of the right size
but with a different type. We already handle this case correctly later on
and generate a bitcast. This commit just makes sure that we are actually
checking the property that we care about.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241312 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-02 23:23:52 +00:00
Akira Hatanaka
516286ff69 Use function attribute "trap-func-name" and remove TargetOptions::TrapFuncName.
This commit changes normal isel and fast isel to read the user-defined trap
function name from function attribute "trap-func-name" attached to llvm.trap or
llvm.debugtrap instead of from TargetOptions::TrapFuncName. This is needed to
use clang's command line option "-ftrap-function" for LTO and enable changing
the trap function name on a per-call-site basis.

Out-of-tree projects currently using TargetOptions::TrapFuncName to specify the
trap function name should attach attribute "trap-func-name" to the call sites
of llvm.trap and llvm.debugtrap instead.

rdar://problem/21225723

Differential Revision: http://reviews.llvm.org/D10832


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241305 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-02 22:13:27 +00:00
Pawel Bylica
074d71dea6 Reapply r240291: Fix shl folding in DAG combiner.
The code responsible for shl folding in the DAGCombiner was assuming incorrectly that all constants are less than 64 bits. This patch simply changes the way values are compared.

It has been reverted previously because of some problems with comparing APInt with raw uint64_t. That has been fixed/changed with r241204.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241254 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-02 11:44:54 +00:00
Sanjoy Das
d0872b393c [NFC] Make the Statepoint class more like CallSite
Summary: Rename some methods to make Statepoint look more like CallSite.

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10756

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241235 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-02 02:53:45 +00:00
Benjamin Kramer
3690da1dfa [SDAG] Give InstrEmitter hidden visibility
NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241165 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-01 14:55:10 +00:00
Pawel Bylica
4c81aa2602 [DAGCombiner] Fix & simplify constant folding of sext/zext.
Summary: This patch fixes the cases of sext/zext constant folding in DAG combiner where constans do not fit 64 bits. The fix simply removes un$

Test Plan: New regression test included.

Reviewers: RKSimon

Reviewed By: RKSimon

Subscribers: RKSimon, llvm-commits

Differential Revision: http://reviews.llvm.org/D10607

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240991 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-29 20:28:47 +00:00
Benjamin Kramer
45b5f7e457 [SDAG] Now that we have a way to communicate the exact bit on sdiv use it to simplify sdiv by a constant.
We had a hack in SDAGBuilder in place to work around this but now we
can avoid that. Call BuildExactSDIV from BuildSDIV so DAGCombiner can
perform this trick automatically.

The added check in DAGCombiner is necessary to prevent exact sdiv by pow2
from regressing as the target-specific pow2 lowering is not aware of
exact bits yet.

This is mostly covered by existing tests. One side effect is that we
get the better lowering for exact vector sdivs now too :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240891 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-27 20:33:26 +00:00
Pete Cooper
6d5c43889e Convert a bunch of loops to foreach. NFC.
This uses the new SDNode::op_values() iterator range committed in r240805.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240822 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-26 19:37:02 +00:00
Pete Cooper
a5d25f61ae Wrap assert loops in #ifndef NDEBUG
The body of the loops here only contained asserts.  This triggered an unused variable
warning on release builds and -Werror on the bots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240819 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-26 19:23:20 +00:00
Pete Cooper
e0e37a2382 Convert a bunch of loops to foreach. NFC.
This uses the new SDNode::op_values() iterator range committed in r240805.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240817 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-26 19:18:49 +00:00
Pete Cooper
226505c0a1 Convert a bunch of loops to foreach. NFC.
This uses the new SDNode::op_values() iterator range committed in r240805.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240815 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-26 19:08:33 +00:00
Pete Cooper
e89ab0eff9 Convert a bunch of loops to foreach. NFC.
This uses the new SDNode::op_values() iterator range committed in r240805.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240809 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-26 18:41:54 +00:00
Benjamin Kramer
23a207d839 [DAGCombine] Fix demanded bits computation for exact shifts.
Fixes a miscompilation of MultiSource/Benchmarks/MallocBench/gs

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240796 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-26 16:59:31 +00:00
Benjamin Kramer
875007d3c4 [DAGCombiner] Preserve the exact bit when simplifying SRA to SRL.
Allows more aggressive folding of ashr/shl pairs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240788 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-26 14:51:49 +00:00
Benjamin Kramer
3791d56da6 [DAGCombine] fold (X >>?,exact C1) << C2 --> X << (C2-C1)
Instcombine also does this but many opportunities only become visible
after GEPs are lowered.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240787 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-26 14:51:36 +00:00