Commit Graph

277 Commits

Author SHA1 Message Date
Erik Schnetter 5e93e28d8b Enable constant propagation for more math functions
Constant propagation for single precision math functions (such as
tanf) is already working, but was not enabled. This patch enables
these for many single-precision functions, and adds respective test
cases.

Newly handled functions: acosf asinf atanf atan2f ceilf coshf expf
exp2f fabsf floorf fmodf logf log10f powf sinhf tanf tanhf

llvm-svn: 246194
2015-08-27 19:56:57 +00:00
Erik Schnetter ed6eab32b3 Revert 246186; still breaks on some systems
llvm-svn: 246191
2015-08-27 19:34:14 +00:00
Erik Schnetter 05845d31c9 Enable constant propagation for more math functions
Constant propagation for single precision math functions (such as
tanf) is already working, but was not enabled. This patch enables
these for many single-precision functions, and adds respective test
cases.

Newly handled functions: acosf asinf atanf atan2f ceilf coshf expf
exp2f fabsf floorf fmodf logf log10f powf sinhf tanf tanhf

llvm-svn: 246186
2015-08-27 18:56:23 +00:00
Erik Schnetter a23672626d Revert r246158 since it breaks LLVM.Transforms/ConstProp.calls.ll
llvm-svn: 246166
2015-08-27 17:24:01 +00:00
Erik Schnetter 694bf5c9b5 Enable constant propagation for more math functions
Constant propagation for single precision math functions (such as
tanf) is already working, but was not enabled. This patch enables
these for many single-precision functions, and adds respective test
cases.

Newly handled functions: acosf asinf atanf atan2f ceilf coshf expf
exp2f fabsf floorf fmodf logf log10f powf sinhf tanf tanhf

llvm-svn: 246158
2015-08-27 16:36:37 +00:00
Matt Arsenault 95365ca482 Fix assert when inlining a constantexpr addrspacecast
The pointer size of the addrspacecasted pointer might not have matched,
so this would have hit an assert in accumulateConstantOffset.

I think this was here to allow constant folding of a load of an
addrspacecasted constant. Accumulating the offset through the
addrspacecast doesn't make much sense, so something else is necessary
to allow folding the load through this cast.

llvm-svn: 243300
2015-07-27 18:31:03 +00:00
David Majnemer ed9abe119b [ConstantFolding] Support folding loads from a GlobalAlias
The MSVC ABI requires that we generate an alias for the vtable which
means looking through a GlobalAlias which cannot be overridden improves
our ability to devirtualize.

Found while investigating PR20801.

Patch by Andrew Zhogin!

Differential Revision: http://reviews.llvm.org/D11306

llvm-svn: 242955
2015-07-22 22:29:30 +00:00
Karthik Bhat d818e38ff9 Constfold trunc,rint,nearbyint,ceil and floor using APFloat
A patch by Chakshu Grover!
This patch allows constfolding of trunc,rint,nearbyint,ceil and floor intrinsics using APFloat class.
Differential Revision: http://reviews.llvm.org/D11144

llvm-svn: 242763
2015-07-21 08:52:23 +00:00
Karthik Bhat d2bc0d8423 Allow constfolding of llvm.sin.* and llvm.cos.* intrinsics
This patch const folds llvm.sin.* and llvm.cos.* intrinsics whenever feasible.

Differential Revision: http://reviews.llvm.org/D10836

llvm-svn: 241665
2015-07-08 03:55:47 +00:00
Andrea Di Biagio 2905999c22 [ConstantFolding] Fix wrong folding of intrinsic 'convert.from.fp16'.
Function 'ConstantFoldScalarCall' (in ConstantFolding.cpp) works under the
wrong assumption that a call to 'convert.from.fp16' returns a value of
type 'float'.
However, intrinsic 'convert.from.fp16' can be overloaded; for example, we
can call 'convert.from.fp16.f64' to convert from half to double; etc.

Before this patch, the following example would have triggered an assertion
failure in opt (with -constprop):

```
define double @foo() {
entry:
  %0 = call double @llvm.convert.from.fp16.f64(i16 0)
  ret double %0
}
```

This patch fixes the problem in ConstantFolding.cpp. When folding a call to
convert.from.fp16, we perform a different kind of conversion based on the call
return type.

Added test 'Transform/ConstProp/convert-from-fp16.ll'.

Differential Revision: http://reviews.llvm.org/D9771

llvm-svn: 237377
2015-05-14 18:01:48 +00:00
Pete Cooper 833f34d837 Convert PHI getIncomingValue() to foreach over incoming_values(). NFC.
We already had a method to iterate over all the incoming values of a PHI.  This just changes all eligible code to use it.

Ineligible code included anything which cared about the index, or was also trying to get the i'th incoming BB.

llvm-svn: 237169
2015-05-12 20:05:31 +00:00
Vince Harron d528112b41 Added support for building against Android API-9 SDK
Created an abstraction for log2, llvm::Log2 in Support/MathExtras.h

Hid Android problems inside of it

Differential Revision: http://reviews.llvm.org/D9467

llvm-svn: 236680
2015-05-07 00:05:26 +00:00
David Blaikie 4a2e73b066 [opaque pointer type] API migration for GEP constant factories
Require the pointee type to be passed explicitly and assert that it is
correct. For now it's possible to pass nullptr here (and I've done so in
a few places in this patch) but eventually that will be disallowed once
all clients have been updated or removed. It'll be a long road to get
all the way there... but if you have the cahnce to update your callers
to pass the type explicitly without depending on a pointer's element
type, that would be a good thing to do soon and a necessary thing to do
eventually.

llvm-svn: 233938
2015-04-02 18:55:32 +00:00
David Blaikie d288fb8681 [opaque pointer type] Change GetElementPtrInst::getIndexedType to take the pointee type
This pushes the use of PointerType::getElementType up into several
callers - I'll essentially just have to keep pushing that up the stack
until I can eliminate every call to it...

llvm-svn: 233604
2015-03-30 21:41:43 +00:00
Mehdi Amini a28d91d81b DataLayout is mandatory, update the API to reflect it with references.
Summary:
Now that the DataLayout is a mandatory part of the module, let's start
cleaning the codebase. This patch is a first attempt at doing that.

This patch is not exactly NFC as for instance some places were passing
a nullptr instead of the DataLayout, possibly just because there was a
default value on the DataLayout argument to many functions in the API.
Even though it is not purely NFC, there is no change in the
validation.

I turned as many pointer to DataLayout to references, this helped
figuring out all the places where a nullptr could come up.

I had initially a local version of this patch broken into over 30
independant, commits but some later commit were cleaning the API and
touching part of the code modified in the previous commits, so it
seemed cleaner without the intermediate state.

Test Plan:

Reviewers: echristo

Subscribers: llvm-commits

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231740
2015-03-10 02:37:25 +00:00
Benjamin Kramer 37dce44f73 Drop the hacks used for partial C99 math libraries.
All supported platforms have half-way decent C99 support.

llvm-svn: 231679
2015-03-09 18:35:18 +00:00
Chandler Carruth 62d4215baa [PM] Move TargetLibraryInfo into the Analysis library.
While the term "Target" is in the name, it doesn't really have to do
with the LLVM Target library -- this isn't an abstraction which LLVM
targets generally need to implement or extend. It has much more to do
with modeling the various runtime libraries on different OSes and with
different runtime environments. The "target" in this sense is the more
general sense of a target of cross compilation.

This is in preparation for porting this analysis to the new pass
manager.

No functionality changed, and updates inbound for Clang and Polly.

llvm-svn: 226078
2015-01-15 02:16:27 +00:00
David Blaikie 70573dcd9f Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool>
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.

This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...

llvm-svn: 222334
2014-11-19 07:49:26 +00:00
Bruno Cardoso Lopes c29520c5b3 [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
Matt Arsenault d6511b49ac Add minnum / maxnum intrinsics
These are named following the IEEE-754 names for these
functions, rather than the libm fmin / fmax to avoid
possible ambiguities. Some languages may implement something
resembling fmin / fmax which return NaN if either operand is
to propagate errors. These implement the IEEE-754 semantics
of returning the other operand if either is a NaN representing
missing data.

llvm-svn: 220341
2014-10-21 23:00:20 +00:00
Sanjay Patel 0d7dee654d Remove duplicate function names from comments. NFC.
llvm-svn: 218875
2014-10-02 15:13:22 +00:00
Sanjay Patel 7b2cd9ad86 Make the sqrt intrinsic return undef for a negative input.
As discussed here:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20140609/220598.html

And again here:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-September/077168.html

The sqrt of a negative number when using the llvm intrinsic is undefined. 
We should return undef rather than 0.0 to match the definition in the LLVM IR lang ref.

This change should not affect any code that isn't using "no-nans-fp-math"; 
ie, no-nans is a requirement for generating the llvm intrinsic in place of a sqrt function call.

Unfortunately, the behavior introduced by this patch will not match current gcc, xlc, icc, and 
possibly other compilers. The current clang/llvm behavior of returning 0.0 doesn't either. 
We knowingly approve of this difference with the other compilers in an attempt to flag code 
that is invoking undefined behavior.

A front-end warning should also try to convince the user that the program will fail:
http://llvm.org/bugs/show_bug.cgi?id=21093

Differential Revision: http://reviews.llvm.org/D5527

llvm-svn: 218803
2014-10-01 20:36:33 +00:00
Craig Topper 71b7b68b74 Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.
llvm-svn: 216158
2014-08-21 05:55:13 +00:00
Craig Topper 6230691c91 Revert "Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size."
Getting a weird buildbot failure that I need to investigate.

llvm-svn: 215870
2014-08-18 00:24:38 +00:00
Craig Topper 5229cfd163 Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.
llvm-svn: 215868
2014-08-17 23:47:00 +00:00
Matt Arsenault caa9c71f32 Look through addrspacecast in IsConstantOffsetFromGlobal
llvm-svn: 213000
2014-07-14 22:39:26 +00:00
Alp Toker 51420a8d62 Remove old fenv.h workaround for a historic clang driver bug
Tested and works fine with clang using libstdc++.

All indications are that this was fixed some time ago and isn't a problem with
any clang version we support.

I've added a note in PR6907 which is still open for some reason.

llvm-svn: 210485
2014-06-09 19:00:52 +00:00
Alp Toker c817d6a5b5 Fold FEnv.h into the implementation
Support headers shouldn't use config.h definitions, and they should never be
undefined like this.

ConstantFolding.cpp was the only user of this facility and already includes
config.h for other math features, so it makes sense to move the checks there at
point of use.

(The implicit config.h was also quite dangerous -- removing the FEnv.h include
would have silently disabled math constant folding without causing any tests to
fail. Need to investigate -Wundef once the cleanup is done.)

This eliminates the last config.h include from LLVM headers, paving the way for
more consistent configuration checks.

llvm-svn: 210483
2014-06-09 18:28:53 +00:00
Rafael Espindola 78598d9ab5 Add a Constant version of stripPointerCasts.
Thanks to rnk for the suggestion.

llvm-svn: 210205
2014-06-04 19:01:48 +00:00
Chandler Carruth a0e5695ad9 Teach the constant folder to look through bitcast constant expressions
much more effectively when trying to constant fold a load of a constant.
Previously, we only handled bitcasts by trying to find a totally generic
byte representation of the constant and use that. Now, we look through
the bitcast to see what constant we might fold the load into, and then
try to form a constant expression cast of the found value that would be
equivalent to loading the value.

You might wonder why on earth this actually matters. Well, turns out
that the Itanium ABI causes us to create a single array for a vtable
where the first elements are virtual base offsets, followed by the
virtual function pointers. Because the array is homogenous the element
type is consistently i8* and we inttoptr the virtual base offsets into
the initial elements.

Then constructors bitcast these pointers to i64 pointers prior to
loading them. Boom, no more constant folding of virtual base offsets.
This is the first fix to LLVM to address the *insane* performance Eric
Niebler discovered with Clang on his range comprehensions[1]. There is
more to come though, this doesn't *really* fix the problem fully.

[1]: http://ericniebler.com/2014/04/27/range-comprehensions/

llvm-svn: 208856
2014-05-15 09:56:28 +00:00
Jay Foad a0653a3e6c Rename ComputeMaskedBits to computeKnownBits. "Masked" has been
inappropriate since it lost its Mask parameter in r154011.

llvm-svn: 208811
2014-05-14 21:14:37 +00:00
Craig Topper 9f008867c0 [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr.
llvm-svn: 206243
2014-04-15 04:59:12 +00:00
Karthik Bhat 195e9dd91b Allow constant folding of ceil function whenever feasible
llvm-svn: 204583
2014-03-24 04:36:06 +00:00
Karthik Bhat b67688a87c Allow constant folding of round function whenever feasible
llvm-svn: 203198
2014-03-07 04:36:21 +00:00
Karthik Bhat daa8cd10d9 Allow constant folding of copysign
llvm-svn: 203076
2014-03-06 05:32:52 +00:00
Benjamin Kramer 061d147f74 ConstantFolding: Also fold the vector overloads of our math intrinsics.
llvm-svn: 202997
2014-03-05 19:41:48 +00:00
Matt Arsenault 8377858c55 Allow constant folding of fma and fmuladd
llvm-svn: 202914
2014-03-05 00:02:00 +00:00
Matt Arsenault f8ecf9b447 Fix duplicate code in ConstantFolding
llvm-svn: 202913
2014-03-05 00:01:58 +00:00
Chandler Carruth 03eb0de93d [Modules] Move GetElementPtrTypeIterator into the IR library. As its
name might indicate, it is an iterator over the types in an instruction
in the IR.... You see where this is going.

Another step of modularizing the support library.

llvm-svn: 202815
2014-03-04 10:40:04 +00:00
Matt Arsenault b03bd4d96b Add addrspacecast instruction.
Patch by Michele Scandale!

llvm-svn: 194760
2013-11-15 01:34:59 +00:00
Matt Arsenault a8e894405c Fix another constant folding address space place I missed.
This fixes an assertion failure with a different sized address space.

llvm-svn: 194014
2013-11-04 20:46:52 +00:00
Matt Arsenault d12e8020ec Fix a constant folding address space place I missed.
If address space 0 was smaller than the address space
in a constant inttoptr/ptrtoint pair, the wrong mask size
would be used.

llvm-svn: 190899
2013-09-17 23:23:16 +00:00
Matt Arsenault bed5bf2e90 Move variable under condition where it is used
llvm-svn: 190567
2013-09-12 01:07:58 +00:00
Matt Arsenault 7a960a8455 Teach ConstantFolding about pointer address spaces
llvm-svn: 188831
2013-08-20 21:20:04 +00:00
Matt Arsenault 8c789099b9 Slightly simplify code with helper functions
e.g. Use Ty->getPointerElementType()
instead of cast<PointerType>(Ty)->getElementType()

llvm-svn: 188223
2013-08-12 23:15:58 +00:00
Matt Arsenault a5e5698441 Add some braces, and spaces around operators
llvm-svn: 188219
2013-08-12 22:56:15 +00:00
Benjamin Kramer ec1bb4fdaf ConstantFolding: ComputeMaskedBits wants the scalar size for vectors.
Fixes PR15791.

llvm-svn: 179859
2013-04-19 16:56:24 +00:00
Benjamin Kramer 89ca4bc6d4 Fix a scalability issue with complex ConstantExprs.
This is basically the same fix in three different places. We use a set to avoid
walking the whole tree of a big ConstantExprs multiple times.

For example: (select cmp, (add big_expr 1), (add big_expr 2))
We don't want to visit big_expr twice here, it may consist of thousands of
nodes.

The testcase exercises this by creating an insanely large ConstantExprs out of
a loop. It's questionable if the optimizer should ever create those, but this
can be triggered with real C code. Fixes PR15714.

llvm-svn: 179458
2013-04-13 12:53:18 +00:00
Michael Ilseman a7b93c1e5f Constant fold vector bitcasts of halves similarly to how floats and doubles are folded. Test case included.
llvm-svn: 176131
2013-02-26 22:51:07 +00:00
Chad Rosier c0955a57df Formatting.
llvm-svn: 175692
2013-02-20 23:57:30 +00:00