1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-10-21 03:53:04 +02:00
Commit Graph

179 Commits

Author SHA1 Message Date
Benjamin Kramer
90b7dad7cf [InstSimplify] Fold away ord/uno fcmps when nnan is present.
This is important to fold away the slow case of complex multiplies
emitted by clang.

llvm-svn: 241911
2015-07-10 14:02:02 +00:00
David Majnemer
c8b1f095a3 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
Benjamin Kramer
ed6c97dbb7 [InstSimplify] Allow folding of fdiv X, X with just NaNs ignored
Any combination of +-inf/+-inf is NaN so it's already ignored with
nnan and we can skip checking for ninf. Also rephrase logic in comments
a bit.

llvm-svn: 239821
2015-06-16 14:57:29 +00:00
Benjamin Kramer
ea33a66cc1 [InstSimplify] fsub nnan x, x -> 0.0 is valid without ninf
Both inf - inf and (-inf) - (-inf) are NaN, so it's already covered by
nnan.

llvm-svn: 239702
2015-06-14 21:01:20 +00:00
Benjamin Kramer
fea304711c [InstSimplify] Add self-fdiv identities for -ffinite-math-only.
When NaNs and Infs are ignored we can fold
 X /  X -> 1.0
-X /  X -> -1.0
 X / -X -> -1.0

llvm-svn: 239701
2015-06-14 18:53:58 +00:00
David Majnemer
e7a303ac2b [InstSimplify] Handle some overflow intrinsics in InstSimplify
This change does a few things:
- Move some InstCombine transforms to InstSimplify
- Run SimplifyCall from within InstCombine::visitCallInst
- Teach InstSimplify to fold [us]mul_with_overflow(X, undef) to 0.

llvm-svn: 237995
2015-05-22 03:56:46 +00:00
David Blaikie
dfadb4e9ee [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
Ahmed Bougacha
b8ea46fe37 Add a bunch of CHECK missing colons in tests. NFC.
Some wouldn't pass;  fixed most, the rest will be fixed separately.

llvm-svn: 232239
2015-03-14 01:43:57 +00:00
David Blaikie
3ea2df7c7b [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
David Blaikie
ab043ff680 [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
0d99339102 [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
Sanjay Patel
5a3bbd8851 Fix really obscure bug in CannotBeNegativeZero() (PR22688)
With a diabolically crafted test case, we could recurse
through this code and return true instead of false.

The larger engineering crime is the use of magic numbers. 
Added FIXME comments for those.

llvm-svn: 230515
2015-02-25 18:00:15 +00:00
Mehdi Amini
1b3cca0d56 InstSimplify: simplify 0 / X if nnan and nsz
From: Fiona Glaser <fglaser@apple.com>
llvm-svn: 230238
2015-02-23 18:30:25 +00:00
David Majnemer
2b452a1df4 IR: Properly return nullptr when getAggregateElement is out-of-bounds
We didn't properly handle the out-of-bounds case for
ConstantAggregateZero and UndefValue.  This would manifest as a crash
when the constant folder was asked to fold a load of a constant global
whose struct type has no operands.

This fixes PR22595.

llvm-svn: 229352
2015-02-16 04:02:09 +00:00
Elena Demikhovsky
e46025656d Fold fcmp in cases where value is provably non-negative. By Arch Robison.
This patch folds fcmp in some cases of interest in Julia. The patch adds a function CannotBeOrderedLessThanZero that returns true if a value is provably not less than zero. I.e. the function returns true if the value is provably -0, +0, positive, or a NaN. The patch extends InstructionSimplify.cpp to fold instances of fcmp where:
 - the predicate is olt or uge
 - the first operand is provably not less than zero
 - the second operand is zero
The motivation for handling these cases optimizing away domain checks for sqrt in Julia for common idioms such as sqrt(x*x+y*y)..

http://reviews.llvm.org/D6972

llvm-svn: 227298
2015-01-28 08:03:58 +00:00
David Majnemer
e2cf8f21e0 InstSimplify: Optimize away pointless comparisons
(X & INT_MIN) ? X & INT_MAX : X  into  X & INT_MAX
(X & INT_MIN) ? X : X & INT_MAX  into  X
(X & INT_MIN) ? X | INT_MIN : X  into  X
(X & INT_MIN) ? X : X | INT_MIN  into  X | INT_MIN

llvm-svn: 224669
2014-12-20 03:04:38 +00:00
David Majnemer
273acc7601 ConstantFold: Shifting undef by zero results in undef
llvm-svn: 224553
2014-12-18 23:54:43 +00:00
David Majnemer
fe299df41a InstSimplify: shl nsw/nuw undef, %V -> undef
We can always choose an value for undef which might cause %V to shift
out an important bit except for one case, when %V is zero.

However, shl behaves like an identity function when the right hand side
is zero.

llvm-svn: 224405
2014-12-17 01:54:33 +00:00
David Majnemer
1181854a21 InstSimplify: Remove usesless %a parameter from tests
No functional change intended.

llvm-svn: 224016
2014-12-11 12:56:17 +00:00
David Majnemer
56c5d273bf ConstantFold: an undef shift amount results in undef
X shifted by undef results in undef because the undef value can
represent values greater than the width of the operands.

llvm-svn: 223968
2014-12-10 21:38:05 +00:00
David Majnemer
fdaa66cd59 ConstantFold: div undef, 0 should fold to undef, not zero
Dividing by zero yields an undefined value.

llvm-svn: 223924
2014-12-10 09:14:55 +00:00
David Majnemer
59eb07e1c0 InstSimplify: [al]shr exact undef, %X -> undef
Exact shifts always keep the non-zero bits of their input.  This means
it keeps it's undef bits.

llvm-svn: 223923
2014-12-10 09:14:52 +00:00
David Majnemer
8ec2668c75 InstSimplify: div %X, 0 -> undef
We already optimized rem %X, 0 to undef, we should do the same for div.

llvm-svn: 223919
2014-12-10 07:52:18 +00:00
David Majnemer
be867a5e8b InstSimplify: Try to bring back the rest of r223583
This reverts r223624 with a small tweak, hopefully this will make stage3
equivalent.

llvm-svn: 223679
2014-12-08 18:30:43 +00:00
NAKAMURA Takumi
953adcfdf0 Revert a part of r223583, for now. It seems causing different emission between stage2(gcc-clang) and stage3 clang. Investigating.
llvm-svn: 223624
2014-12-08 02:07:22 +00:00
David Majnemer
4388d93ae3 InstSimplify: Optimize away useless unsigned comparisons
Code like X < Y && Y == 0 should always be folded away to false.

llvm-svn: 223583
2014-12-06 10:51:40 +00:00
Hal Finkel
207573f122 Revert "r223364 - Revert r223347 which has caused crashes on bootstrap bots."
Reapply r223347, with a fix to not crash on uninserted instructions (or more
precisely, instructions in uninserted blocks). bugpoint was able to reduce the
test case somewhat, but it is still somewhat large (and relies on setting
things up to be simplified during inlining), so I've not included it here.
Nevertheless, it is clear what is going on and why.

Original commit message:

Restrict somewhat the memory-allocation pointer cmp opt from r223093

Based on review comments from Richard Smith, restrict this optimization from
applying to globals that might resolve lazily to other dynamically-loaded
modules, and also from dynamic allocas (which might be transformed into malloc
calls). In short, take extra care that the compared-to pointer is really
simultaneously live with the memory allocation.

llvm-svn: 223371
2014-12-04 17:45:19 +00:00
Alexander Potapenko
a5817ca5e9 Revert r223347 which has caused crashes on bootstrap bots.
llvm-svn: 223364
2014-12-04 14:22:27 +00:00
Hal Finkel
a127d156af Restrict somewhat the memory-allocation pointer cmp opt from r223093
Based on review comments from Richard Smith, restrict this optimization from
applying to globals that might resolve lazily to other dynamically-loaded
modules, and also from dynamic allocas (which might be transformed into malloc
calls). In short, take extra care that the compared-to pointer is really
simultaneously live with the memory allocation.

llvm-svn: 223347
2014-12-04 09:22:28 +00:00
Hal Finkel
f84be383f3 Simplify pointer comparisons involving memory allocation functions
System memory allocation functions, which are identified at the IR level by the
noalias attribute on the return value, must return a pointer into a memory region
disjoint from any other memory accessible to the caller. We can use this
property to simplify pointer comparisons between allocated memory and local
stack addresses and the addresses of global variables. Neither the stack nor
global variables can overlap with the region used by the memory allocator.

Fixes PR21556.

llvm-svn: 223093
2014-12-01 23:38:06 +00:00
David Majnemer
d9ae958b9b InstSimplify: Restore optimizations lost in r210006
This restores our ability to optimize:
(X & C) ? X & ~C : X  into  X & ~C
(X & C) ? X : X & ~C  into  X
(X & C) ? X | C : X  into  X
(X & C) ? X : X | C  into  X | C

llvm-svn: 222868
2014-11-27 06:32:46 +00:00
David Majnemer
4e5c0f46f5 InstSimplify: Handle some simple tautological comparisons
This handles cases where we are comparing a masked value against itself.
The analysis could be further improved by making it recursive but such
expense is not currently justified.

llvm-svn: 222716
2014-11-25 02:55:48 +00:00
David Majnemer
26583aff1f InstSimplify: Simplify (sub 0, X) -> X if it's NUW
This is a generalization of the X - (0 - Y) -> X transform.

llvm-svn: 222611
2014-11-22 07:15:16 +00:00
David Majnemer
a8f61a4be6 InstSimplify: Exact shifts of X by Y are X if X has the lsb set
Exact shifts may not shift out any non-zero bits. Use computeKnownBits
to determine when this occurs and just return the left hand side.

This fixes PR21477.

llvm-svn: 221325
2014-11-05 00:59:59 +00:00
Bruno Cardoso Lopes
245f9d6493 [InstSimplify] Support constant folding to vector of pointers
ConstantFolding crashes when trying to InstSimplify the following load:

@a = private unnamed_addr constant %mst {
     i8* inttoptr (i64 -1 to i8*),
     i8* inttoptr (i64 -1 to i8*)
}, align 8

%x = load <2 x i8*>* bitcast (%mst* @a to <2 x i8*>*), align 8

This patch fix this by adding support to this type of folding:

%x = load <2 x i8*>* bitcast (%mst* @a to <2 x i8*>*), align 8
==> gets folded to:
  %x = <2 x i8*> <i8* inttoptr (i64 -1 to i8*), i8* inttoptr (i64 -1 to i8*)>

llvm-svn: 220380
2014-10-22 12:18:48 +00:00
David Majnemer
ebf53c54ae InstCombine: Simplify FoldICmpCstShrCst
This function was complicated by the fact that it tried to perform
canonicalizations that were already preformed by InstSimplify.  Remove
this extra code and move the tests over to InstSimplify.  Add asserts to
make sure our preconditions hold before we make any assumptions.

llvm-svn: 220314
2014-10-21 19:51:55 +00:00
Philip Reames
cb6ff55dfa Introduce a 'nonnull' metadata on Load instructions.
The newly introduced 'nonnull' metadata is analogous to existing 'nonnull' attributes, but applies to load instructions rather than call arguments or returns.  Long term, it would be nice to combine these into a single construct.   The value of the load is allowed to vary between successive loads, but null is not a valid value to be loaded by any load marked nonnull.

Reviewed by: Hal Finkel
Differential Revision:  http://reviews.llvm.org/D5220

llvm-svn: 220240
2014-10-20 22:40:55 +00:00
Hal Finkel
717a51f66b Revert "r216914 - Revert: [APFloat] Fixed a bug in method 'fusedMultiplyAdd'"
Reapply r216913, a fix for PR20832 by Andrea Di Biagio. The commit was reverted
because of buildbot failures, and credit goes to Ulrich Weigand for isolating
the underlying issue (which can be confirmed by Valgrind, which does helpfully
light up like the fourth of July). Uli explained the problem with the original
patch as:

  It seems the problem is calling multiplySignificand with an addend of category
  fcZero; that is not expected by this routine.  Note that for fcZero, the
  significand parts are simply uninitialized, but the code in (or rather, called
  from) multiplySignificand will unconditionally access them -- in effect using
  uninitialized contents.

This version avoids using a category == fcZero addend within
multiplySignificand, which avoids this problem (the Valgrind output is also now
clean).

Original commit message:

[APFloat] Fixed a bug in method 'fusedMultiplyAdd'.

When folding a fused multiply-add builtin call, make sure that we propagate the
correct result in the case where the addend is zero, and the two other operands
are finite non-zero.

Example:
  define double @test() {
    %1 = call double @llvm.fma.f64(double 7.0, double 8.0, double 0.0)
    ret double %1
  }

Before this patch, the instruction simplifier wrongly folded the builtin call
in function @test to constant 'double 7.0'.
With this patch, method 'fusedMultiplyAdd' correctly evaluates the multiply and
propagates the expected result (i.e. 56.0).

Added test fold-builtin-fma.ll with the reproducible from PR20832 plus extra
test cases to verify the behavior of method 'fusedMultiplyAdd' in the presence
of NaN/Inf operands.

This fixes PR20832.

llvm-svn: 219708
2014-10-14 19:23:07 +00:00
David Majnemer
475b056c9a InstCombine, InstSimplify: (%X /s C1) /s C2 isn't always 0 when C1 * C2 overflow
consider:
C1 = INT_MIN
C2 = -1

C1 * C2 overflows without a doubt but consider the following:
%x = i32 INT_MIN

This means that (%X /s C1) is 1 and (%X /s C1) /s C2 is -1.

N. B.  Move the unsigned version of this transform to InstSimplify, it
doesn't create any new instructions.

This fixes PR21243.

llvm-svn: 219567
2014-10-11 10:20:01 +00:00
David Majnemer
780406b9cc InstSimplify: Don't allow (x srem y) urem y -> x srem y
Let's consider the case where:
%x i16 = 32768
%y i16 = 384

%x srem %y = 65408
(%x srem %y) urem %y = 128

llvm-svn: 217939
2014-09-17 04:16:35 +00:00
David Majnemer
9a670c8293 InstSimplify: ((X % Y) % Y) -> (X % Y)
Patch by Sonam Kumari!

Differential Revision: http://reviews.llvm.org/D5350

llvm-svn: 217937
2014-09-17 03:34:34 +00:00
David Majnemer
9985d36f3b InstSimplify: Simplify trivial and/or of icmps
Some ICmpInsts when anded/ored with another ICmpInst trivially reduces
to true or false depending on whether or not all integers or no integers
satisfy the intersected/unioned range.

This sort of trivial looking code can come about when InstCombine
performs a range reduction-type operation on sdiv and the like.

This fixes PR20916.

llvm-svn: 217750
2014-09-15 08:15:28 +00:00
Andrea Di Biagio
ef361be676 Revert: [APFloat] Fixed a bug in method 'fusedMultiplyAdd'.
This reverts revision 216913; the new test added at revision 216913
caused regression failures on a couple of buildbots.

llvm-svn: 216914
2014-09-02 17:22:49 +00:00
Andrea Di Biagio
2b24c712b1 [APFloat] Fixed a bug in method 'fusedMultiplyAdd'.
When folding a fused multiply-add builtin call, make sure that we propagate the
correct result in the case where the addend is zero, and the two other operands
are finite non-zero.

Example:
  define double @test() {
    %1 = call double @llvm.fma.f64(double 7.0, double 8.0, double 0.0)
    ret double %1
  }

Before this patch, the instruction simplifier wrongly folded the builtin call
in function @test to constant 'double 7.0'.
With this patch, method 'fusedMultiplyAdd' correctly evaluates the multiply and
propagates the expected result (i.e. 56.0).

Added test fold-builtin-fma.ll with the reproducible from PR20832 plus extra
test cases to verify the behavior of method 'fusedMultiplyAdd' in the presence
of NaN/Inf operands.

This fixes PR20832.

Differential Revision: http://reviews.llvm.org/D5152

llvm-svn: 216913
2014-09-02 16:44:56 +00:00
David Majnemer
e48fe8e34c InstSimplify: Move a transform from InstCombine to InstSimplify
Several combines involving icmp (shl C2, %X) C1 can be simplified
without introducing any new instructions.  Move them to InstSimplify;
while we are at it, make them more powerful.

llvm-svn: 216642
2014-08-28 03:34:28 +00:00
David Majnemer
26488cdc00 InstSimplify: Don't simplify gep X, (Y-X) to Y if types differ
It's incorrect to perform this simplification if the types differ.
A bitcast would need to be inserted for this to work.

This fixes PR20771.

llvm-svn: 216597
2014-08-27 20:08:34 +00:00
Nico Weber
6595699903 Reland r216439 215441, majnemer has a real fix for PR20771.
llvm-svn: 216586
2014-08-27 20:06:19 +00:00
Nico Weber
10e86f2a15 Revert r216439 (and r216441, else the former doesn't revert cleanly).
It caused PR 20771. I'll land a test on the clang side.

llvm-svn: 216582
2014-08-27 20:00:13 +00:00
David Majnemer
6ca502a667 InstSimplify: Compute comparison ranges for left shift instructions
'shl nuw CI, x' produces [CI, CI << CLZ(CI)]
'shl nsw CI, x' produces [CI << CLO(CI)-1, CI] if CI is negative
'shl nsw CI, x' produces [CI, CI << CLZ(CI)-1] if CI is non-negative

llvm-svn: 216570
2014-08-27 18:03:46 +00:00
David Majnemer
635dd8cd82 InstSimplify: Fold gep X, (sub 0, ptrtoint(X)) to null
Save InstCombine some work if we can perform this fold during
InstSimplify.

llvm-svn: 216441
2014-08-26 07:08:03 +00:00