195 Commits

Author SHA1 Message Date
Reid Kleckner
27d17d1713 Rename AttributeSet to AttributeList
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.

Rename AttributeSetImpl to AttributeListImpl to follow suit.

It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.

Reviewers: sanjoy, javed.absar, chandlerc, pete

Reviewed By: pete

Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits

Differential Revision: https://reviews.llvm.org/D31102

llvm-svn: 298393
2017-03-21 16:57:19 +00:00
Justin Lebar
a8dfb91650 [LangRef] Make @llvm.sqrt(x) return undef, rather than have UB, for negative x.
Summary:
Some frontends emit a speculate-and-select idiom for sqrt, wherein they compute
sqrt(x), check if x is negative, and select NaN if it is:

  %cmp = fcmp olt double %a, -0.000000e+00
  %sqrt = call double @llvm.sqrt.f64(double %a)
  %ret = select i1 %cmp, double 0x7FF8000000000000, double %sqrt

This is technically UB as the LangRef is written today if %a is ever less than
-0.  But emitting code that's compliant with the current definition of sqrt
would require a branch, which would then prevent us from matching this idiom in
SelectionDAG (which we do today -- ISD::FSQRT has defined behavior on negative
inputs), because SelectionDAG looks at one BB at a time.

Nothing in LLVM takes advantage of this undefined behavior, as far as we can
tell, and the fact that llvm.sqrt has UB dates from its initial addition to the
LangRef.

Reviewers: arsenm, mehdi_amini, hfinkel

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D28797

llvm-svn: 293242
2017-01-27 00:58:03 +00:00
Matt Arsenault
4249853cf1 SimplifyLibCalls: Replace more unary libcalls with intrinsics
llvm-svn: 292855
2017-01-23 23:55:08 +00:00
David L. Jones
268960185f [Analysis] Add LibFunc_ prefix to enums in TargetLibraryInfo. (NFC)
Summary:
The LibFunc::Func enum holds enumerators named for libc functions.
Unfortunately, there are real situations, including libc implementations, where
function names are actually macros (musl uses "#define fopen64 fopen", for
example; any other transitively visible macro would have similar effects).

Strictly speaking, a conforming C++ Standard Library should provide any such
macros as functions instead (via <cstdio>). However, there are some "library"
functions which are not part of the standard, and thus not subject to this
rule (fopen64, for example). So, in order to be both portable and consistent,
the enum should not use the bare function names.

The old enum naming used a namespace LibFunc and an enum Func, with bare
enumerators. This patch changes LibFunc to be an enum with enumerators prefixed
with "LibFFunc_". (Unfortunately, a scoped enum is not sufficient to override
macros.)

There are additional changes required in clang.

Reviewers: rsmith

Subscribers: mehdi_amini, mzolotukhin, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D28476

llvm-svn: 292848
2017-01-23 23:16:46 +00:00
Matt Arsenault
018a8adda0 SimplifyLibCalls: Remove checks for fabs
Use the intrinsic instead of emitting the libcall which
will be replaced by the intrinsic.

llvm-svn: 292176
2017-01-17 00:30:31 +00:00
Matt Arsenault
ccfb3dd68e SimplifyLibCalls: Replace fabs libcalls with intrinsics
Add missing fabs(fpext) optimzation that worked with the call,
and also fixes it creating a second fpext when there were multiple
uses.

llvm-svn: 292172
2017-01-17 00:10:40 +00:00
Davide Italiano
ba6e5d0a9e [SimplifyLibCalls] Propagate fast math flags while optimizing pow().
llvm-svn: 291577
2017-01-10 18:02:05 +00:00
Davide Italiano
bc2b08fb6d [SimplifyLibCalls] pow(x, -0.5) -> 1.0 / sqrt(x).
Differential Revision:  https://reviews.llvm.org/D28479

llvm-svn: 291486
2017-01-09 21:55:23 +00:00
Matt Arsenault
b5e40e0ffe SimplifyLibCalls: Remove incorrect optimization of fabs
fabs(x * x) is not generally safe to assume x is positive if x is a NaN.
This is also less general than it could be, so this will be replaced
with a transformation on the intrinsic.

llvm-svn: 291359
2017-01-07 19:55:12 +00:00
Daniel Jasper
162ffcacd6 Revert @llvm.assume with operator bundles (r289755-r289757)
This creates non-linear behavior in the inliner (see more details in
r289755's commit thread).

llvm-svn: 290086
2016-12-19 08:22:17 +00:00
Davide Italiano
c2513a6aa0 [SimplifyLibCalls] Use a lambda. NFCI.
llvm-svn: 289911
2016-12-16 02:28:38 +00:00
Davide Italiano
1b19bf8526 [SimplifyLibCalls] Lower fls() to llvm.ctlz().
Differential Revision:  https://reviews.llvm.org/D14590

llvm-svn: 289894
2016-12-15 23:45:11 +00:00
Davide Italiano
71113df20d [SimplifyLibCalls] Remove redundant folding logic for ffs().
Lowering to llvm.cttz() will result in constant folding anyway
if the argument to ffs is a constant. Pointed out by Eli for
fls() in D14590.

llvm-svn: 289888
2016-12-15 23:11:00 +00:00
Hal Finkel
f224db75d2 Remove the AssumptionCache
After r289755, the AssumptionCache is no longer needed. Variables affected by
assumptions are now found by using the new operand-bundle-based scheme. This
new scheme is more computationally efficient, and also we need much less
code...

llvm-svn: 289756
2016-12-15 03:02:15 +00:00
Stephan Bergmann
aba15d97df Replace APFloatBase static fltSemantics data members with getter functions
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
2016-12-14 11:57:17 +00:00
Sam Parker
76f0fe4eea Enable simplify libcalls for ARM PCS
Teach SimplifyLibcalls that in can treat functions annotated with
apcs, aapcs or aapcs_vfp like normal C functions if they only take
and return integer or pointer values, and the target is not iOS.

Differential Revision: https://reviews.llvm.org/D24453

llvm-svn: 281322
2016-09-13 12:10:14 +00:00
David Majnemer
5423e4bff5 Use range algorithms instead of unpacking begin/end
No functionality change is intended.

llvm-svn: 278417
2016-08-11 21:15:00 +00:00
Davide Italiano
767e338578 [SimplifyLibCalls] Restore the old behaviour, emit a libcall.
Hal pointed out that the semantic of our intrinsic and the libc
call are slightly different. Add a comment while I'm here to
explain why we can't emit an intrinsic. Thanks Hal!

llvm-svn: 278200
2016-08-10 06:33:32 +00:00
Davide Italiano
d5f633ab43 [SimplifyLibCalls] Emit sqrt intrinsic instead of a libcall.
llvm-svn: 277972
2016-08-08 03:23:01 +00:00
Davide Italiano
fa5db7cc65 [SLC] Emit an intrinsic instead of a libcall for pow.
Differential Revision:  https://reviews.llvm.org/D22104

llvm-svn: 277963
2016-08-07 20:27:03 +00:00
Sjoerd Meijer
48e7c80f18 Addressing post-commit comments for not rewriting fputs:
moved the optimise for size check inside function optimizeFPuts.

llvm-svn: 274758
2016-07-07 14:31:19 +00:00
Sjoerd Meijer
fade1bf838 Code size optimisation: don't rewrite fputs to fwrite when optimising for size
because fwrite requires more arguments and thus extra MOVs are required.

llvm-svn: 274753
2016-07-07 13:56:23 +00:00
Joerg Sonnenberger
30460c8dd2 Optimize a printf with a double procent to putchar.
llvm-svn: 268922
2016-05-09 14:36:16 +00:00
Ahmed Bougacha
fff706e40a [TLI] Unify LibFunc signature checking. NFCI.
I tried to be as close as possible to the strongest check that
existed before; cleaning these up properly is left for future work.

Differential Revision: http://reviews.llvm.org/D19469

llvm-svn: 267758
2016-04-27 19:04:35 +00:00
David Majnemer
67f60eaa89 Revert "[SimplifyLibCalls] sprintf doesn't copy null bytes"
The destination buffer that sprintf uses is restrict qualified, we do
not need to worry about derived pointers referenced via format
specifiers.

This reverts commit r267580.

llvm-svn: 267605
2016-04-26 21:04:47 +00:00
David Majnemer
5541fe7f24 [SimplifyLibCalls] sprintf doesn't copy null bytes
sprintf doesn't read or copy the terminating null byte from it's string
operands.  sprintf will append it's own after processing all of the
format specifiers.

This fixes PR27526.

llvm-svn: 267580
2016-04-26 18:16:49 +00:00
Mehdi Amini
9ff867f98c [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
David L Kreitzer
cc655b3f3d Simplify strlen to a subtraction for certain cases.
Patch by Li Huang (li1.huang@intel.com)

Differential Revision: http://reviews.llvm.org/D18230

llvm-svn: 266200
2016-04-13 14:31:06 +00:00
Davide Italiano
52a0dab957 [SimplifyLibCalls] Garbage collect dead code.
We already skip optimizations if the return value
of printf() is used, so CI->use_empty() is always
true.

Differential Revision:  http://reviews.llvm.org/D18656

llvm-svn: 265253
2016-04-03 01:46:52 +00:00
Davide Italiano
09b1f874a9 [SimplifyLibCalls] Transform printf("%s", "a") -> putchar('a').
llvm-svn: 264588
2016-03-28 15:54:01 +00:00
David Majnemer
ab6aef2bdd [SimplifyLibCalls] Only consider sinpi/cospi functions within the same function
The sinpi/cospi can be replaced with sincospi to remove unnecessary
computations.  However, we need to make sure that the calls are within
the same function!

This fixes PR26993.

llvm-svn: 263875
2016-03-19 04:53:02 +00:00
Sanjay Patel
906306d436 [LibCallSimplifier] fold memset(malloc(x), 0, x) --> calloc(1, x)
This is a step towards solving PR25892:
https://llvm.org/bugs/show_bug.cgi?id=25892

It won't handle the reported case. As noted by the 'TODO' comments in the patch, 
we need to relax the hasOneUse() constraint and also match patterns that include
memset_chk() and the llvm.memset() intrinsic in addition to memset().

Differential Revision: http://reviews.llvm.org/D16337

llvm-svn: 258816
2016-01-26 16:17:24 +00:00
Sanjay Patel
ef7cae166d move function definitions so we don't need separate declarations ; NFCI
llvm-svn: 258455
2016-01-21 23:38:43 +00:00
Sanjay Patel
ff5da390f5 [LibCallSimplifier] refactor FP function signature checks ; NFCI
Use the helper function added in r258428.

The check should really be hoisted to the caller of all of these
optimize* functions, but that's another step.

llvm-svn: 258446
2016-01-21 22:58:01 +00:00
Sanjay Patel
7c9dc49b45 avoid variable shadowing; NFC
llvm-svn: 258445
2016-01-21 22:41:16 +00:00
Sanjay Patel
4a76c00379 remove unnecessary variable; NFC
llvm-svn: 258444
2016-01-21 22:31:18 +00:00
Sanjay Patel
1087b8fb2a [LibCallSimplifier] don't get fooled by a fake fmin()
This is similar to the bug/fix:
https://llvm.org/bugs/show_bug.cgi?id=26211
http://reviews.llvm.org/rL258325

The fmin() test case reveals another bug caused by sloppy
code duplication. It will crash without this patch because
fp128 is a valid floating-point type, but we would think
that we had matched a function that used doubles.

The new helper function can be used to replace similar
checks that are used in several other places in this file.

llvm-svn: 258428
2016-01-21 20:19:54 +00:00
Sanjay Patel
9447739046 make helper functions static; NFCI
llvm-svn: 258416
2016-01-21 18:01:57 +00:00
Sanjay Patel
3635b71b45 [LibCallSimplifier] don't get fooled by a fake sqrt()
The test case will crash without this patch because the subsequent call to
hasUnsafeAlgebra() assumes that the call instruction is an FPMathOperator
(ie, returns an FP type).

This part of the function signature check was omitted for the sqrt() case, 
but seems to be in place for all other transforms.

Before:
http://reviews.llvm.org/rL257400
...we would have needlessly continued execution in optimizeSqrt(), but the
bug was harmless because we'd eventually fail some other check and return
without damage.

This should fix:
https://llvm.org/bugs/show_bug.cgi?id=26211

Differential Revision: http://reviews.llvm.org/D16198

llvm-svn: 258325
2016-01-20 17:41:14 +00:00
Sanjay Patel
73930e2b84 function names start with a lowercase letter; NFC
Note: There are no uses of these functions outside of
SimplifyLibCalls, so they could be static functions in
that file.

llvm-svn: 258172
2016-01-19 19:46:10 +00:00
Sanjay Patel
a2ab3d6165 [LibCallSimplifier] use instruction-level fast-math-flags to shrink calls
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555

llvm-svn: 258158
2016-01-19 18:38:52 +00:00
Sanjay Patel
a46637dede [LibCallSimplifier] use instruction-level fast-math-flags to transform pow(x, [small integer]) calls
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555

As with D15937, the intent of the patch is to preserve the current behavior of the transform
except that we use the pow call's 'fast' attribute as a trigger rather than a function-level
attribute.

The TODO comment notes a potential follow-on patch that would propagate FMF to the new
instructions.

Differential Revision: http://reviews.llvm.org/D16122

llvm-svn: 258153
2016-01-19 18:15:12 +00:00
Sanjay Patel
489a46e98d [LibCallSimplifier] use instruction-level fast-math-flags to transform pow(x, 0.5) calls
Also, propagate the FMF to the newly created sqrt() call.

llvm-svn: 257503
2016-01-12 19:06:35 +00:00
Sanjay Patel
eb6cf93f57 function names start with a lower case letter ; NFC
llvm-svn: 257496
2016-01-12 18:03:37 +00:00
Sanjay Patel
91e6a8ee15 [LibCallSimplifier] use instruction-level fast-math-flags to transform pow(exp(x)) calls
See also:
http://reviews.llvm.org/rL255555
http://reviews.llvm.org/rL256871
http://reviews.llvm.org/rL256964
http://reviews.llvm.org/rL257400
http://reviews.llvm.org/rL257404
http://reviews.llvm.org/rL257414

llvm-svn: 257491
2016-01-12 17:30:37 +00:00
Sanjay Patel
42e7daf81c [LibCallSimplifier] use instruction-level fast-math-flags to transform log calls
Also, add tests to verify that we're checking 'fast' on both calls of each transform pair,
tighten the CHECK lines, and give the tests more meaningful names.

This is a continuation of:
http://reviews.llvm.org/rL255555
http://reviews.llvm.org/rL256871
http://reviews.llvm.org/rL256964
http://reviews.llvm.org/rL257400
http://reviews.llvm.org/rL257404

llvm-svn: 257414
2016-01-11 23:31:48 +00:00
Sanjay Patel
dfd0791d6d [LibCallSimplifier] don't allow sqrt transform unless all ops are unsafe
Fix the FIXME added with:
http://reviews.llvm.org/rL257400

llvm-svn: 257404
2016-01-11 22:50:36 +00:00
Sanjay Patel
68ad8ce279 more space; NFC
llvm-svn: 257401
2016-01-11 22:35:39 +00:00
Sanjay Patel
9ac7e74796 [LibCallSimplifier] use instruction-level fast-math-flags to transform sqrt calls
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555

The intent of the patch is to preserve the current behavior of the transform except
that we use the sqrt instruction's 'fast' attribute as a trigger rather than the
function-level attribute.

But this raises a bug noted by the new FIXME comment.

In order to do this transform:
sqrt((x * x) * y) ---> fabs(x) * sqrt(y)

...we need all of the sqrt, the first fmul, and the second fmul to be 'fast'. 
If any of those ops is strict, we should bail out.

Differential Revision: http://reviews.llvm.org/D15937

llvm-svn: 257400
2016-01-11 22:34:19 +00:00
Sanjay Patel
6307d280cd [LibCallSimplifier] less indenting; NFCI
llvm-svn: 256973
2016-01-06 20:52:21 +00:00