Commit Graph

4893 Commits

Author SHA1 Message Date
Chris Lattner
26698a600e Fix PR3452 (an infinite loop bootstrapping) by disabling the recent
improvements to the EvaluateInDifferentType code.  This code works 
by just inserted a bunch of new code and then seeing if it is 
useful.  Instcombine is not allowed to do this: it can only insert
new code if it is useful, and only when it is converging to a more
canonical fixed point.  Now that we iterate when DCE makes progress,
this causes an infinite loop when the code ends up not being used.

llvm-svn: 63483
2009-01-31 19:05:27 +00:00
Chris Lattner
c4729610fc now that all the pieces are in place, teach instcombine's
simplifydemandedbits to simplify instructions with *multiple
uses* in contexts where it can get away with it.  This allows
it to simplify the code in multi-use-or.ll into a single 'add 
double'.

This change is particularly interesting because it will cover
up for some common codegen bugs with large integers created due
to the recent SROA patch.  When working on fixing those bugs,
this should be disabled.

llvm-svn: 63481
2009-01-31 08:40:03 +00:00
Chris Lattner
85ecfee7f3 simplify/clarify control flow and improve comments, no functionality change.
llvm-svn: 63480
2009-01-31 08:24:16 +00:00
Chris Lattner
a899f8b75d make some fairly meaty internal changes to how SimplifyDemandedBits works.
Now, if it detects that "V" is the same as some other value, 
SimplifyDemandedBits returns the new value instead of RAUW'ing it immediately.
This has two benefits:
1) simpler code in the recursive SimplifyDemandedBits routine.
2) it allows future fun stuff in instcombine where an operation has multiple
   uses and can be simplified in one context, but not all.

#2 isn't implemented yet, this patch should have no functionality change.

llvm-svn: 63479
2009-01-31 08:15:18 +00:00
Chris Lattner
95fe6579dd minor cleanups
llvm-svn: 63477
2009-01-31 07:26:06 +00:00
Chris Lattner
abf34563ec make sure to set Changed=true when instcombine hacks on the code,
not doing so prevents it from properly iterating and prevents it
from deleting the entire body of dce-iterate.ll

llvm-svn: 63476
2009-01-31 07:04:22 +00:00
Chris Lattner
235913be77 Simplify and generalize the SROA "convert to scalar" transformation to
be able to handle *ANY* alloca that is poked by loads and stores of 
bitcasts and GEPs with constant offsets.  Before the code had a number
of annoying limitations and caused it to miss cases such as storing into
holes in structs and complex casts (as in bitfield-sroa) where we had
unions of bitfields etc.  This also handles a number of important cases
that are exposed due to the ABI lowering stuff we do to pass stuff by
value.

One case that is pretty great is that we compile 
2006-11-07-InvalidArrayPromote.ll into:

define i32 @func(<4 x float> %v0, <4 x float> %v1) nounwind {
	%tmp10 = call <4 x i32> @llvm.x86.sse2.cvttps2dq(<4 x float> %v1)
	%tmp105 = bitcast <4 x i32> %tmp10 to i128
	%tmp1056 = zext i128 %tmp105 to i256	
	%tmp.upgrd.43 = lshr i256 %tmp1056, 96
	%tmp.upgrd.44 = trunc i256 %tmp.upgrd.43 to i32	
	ret i32 %tmp.upgrd.44
}

which turns into:

_func:
	subl	$28, %esp
	cvttps2dq	%xmm1, %xmm0
	movaps	%xmm0, (%esp)
	movl	12(%esp), %eax
	addl	$28, %esp
	ret

Which is pretty good code all things considering :).

One effect of this is that SROA will start generating arbitrary bitwidth 
integers that are a multiple of 8 bits.  In the case above, we got a 
256 bit integer, but the codegen guys assure me that it can handle the 
simple and/or/shift/zext stuff that we're doing on these operations.

This addresses rdar://6532315

llvm-svn: 63469
2009-01-31 02:28:54 +00:00
Gabor Greif
690930270b use precise getters
llvm-svn: 63402
2009-01-30 18:21:13 +00:00
Chris Lattner
f9dd07a3c3 Fix some issues with volatility, move "CanConvertToScalar" check
after the others.

llvm-svn: 63227
2009-01-28 20:16:43 +00:00
Duncan Sands
aee16d4916 Rename getAnalysisToUpdate to getAnalysisIfAvailable.
llvm-svn: 63198
2009-01-28 13:14:17 +00:00
Mon P Wang
80efbf07bd Fixed optimization of combining two shuffles where the first shuffle inputs
has a different number of elements than the output.

llvm-svn: 62998
2009-01-26 04:39:00 +00:00
Chris Lattner
f93b292d9b Handle single-entry phi nodes gracefully in condprop.
llvm-svn: 62985
2009-01-26 02:18:20 +00:00
Chris Lattner
5549fb4e74 Fix PR3408 by making a non-obvious assumption very obvious, and
handling the flaw inherent in that assumption.  :)

llvm-svn: 62984
2009-01-26 02:11:30 +00:00
Chris Lattner
e9c2c98b59 More cleanups and simplifications, no functionality change.
llvm-svn: 62983
2009-01-26 01:57:01 +00:00
Chris Lattner
1e52603152 tidy asserts
llvm-svn: 62982
2009-01-26 01:38:24 +00:00
Nick Lewycky
459667b48d The function that does nothing but call malloc is noalias return.
llvm-svn: 62956
2009-01-25 07:59:57 +00:00
Dale Johannesen
b818fa1bd3 Revert previous change; even this mild and clearly
more accurate change loses more than it gains on
benchmarks.

llvm-svn: 62938
2009-01-24 21:49:34 +00:00
Torok Edwin
2a7e7066b3 testcase for PR3381.
Also it was an empty struct, not a void after all.

llvm-svn: 62920
2009-01-24 17:16:04 +00:00
Torok Edwin
726354d4ce void* is represented as pointer to empty struct {}.
Thus we need to check whether the struct is empty before trying to index into
it. This fixes PR3381.

llvm-svn: 62918
2009-01-24 11:30:49 +00:00
Dale Johannesen
1867040e00 Improve the inlining cost function a bit.
Little practical effect.

llvm-svn: 62908
2009-01-24 01:27:33 +00:00
Chris Lattner
d386e82ec9 Make InstCombineStoreToCast handle aggregates more aggressively,
handling the case in Transforms/InstCombine/cast-store-gep.ll, which
is a heavily reduced testcase from Clang on x86-64.

llvm-svn: 62904
2009-01-24 01:00:13 +00:00
Gabor Greif
2d7bf2a76c use CallSite::isCalle instead of slow getOperandNo
llvm-svn: 62877
2009-01-23 21:17:04 +00:00
Gabor Greif
fbd40904c1 Simplify the logic of getting hold of a PHI predecessor block.
There is now a direct way from value-use-iterator to incoming block in PHINode's API.
This way we avoid the iterator->index->iterator trip, and especially the costly
getOperandNo() invocation. Additionally there is now an assertion that the iterator
really refers to one of the PHI's Uses.

llvm-svn: 62869
2009-01-23 19:40:15 +00:00
Gabor Greif
d56b0a8c03 introduce a useful abstraction to find out if a Use is in the call position of an instruction
llvm-svn: 62788
2009-01-22 21:35:57 +00:00
Chris Lattner
ca83aa289a Remove uses of uint32_t in favor of 'unsigned' for better
compatibility with cygwin.  Patch by Jay Foad!

llvm-svn: 62695
2009-01-21 18:09:24 +00:00
Dale Johannesen
6854f86296 Make special cases (0 inf nan) work for frem.
Besides APFloat, this involved removing code
from two places that thought they knew the
result of frem(0., x) but were wrong.

llvm-svn: 62645
2009-01-21 00:35:19 +00:00
Chris Lattner
6ade48fcaa another fix for PR3354
llvm-svn: 62561
2009-01-20 01:15:41 +00:00
Bill Wendling
5281f4fb64 Doxygen-ify comments.
llvm-svn: 62546
2009-01-19 23:43:56 +00:00
Chris Lattner
e8fa6f2468 Fix a problem exposed by PR3354: simplifycfg was making a potentially
trapping instruction be executed unconditionally.

llvm-svn: 62541
2009-01-19 23:03:13 +00:00
Chris Lattner
45a7b5ce57 improve compatibility with cygwin, patch by Jay Foad!
llvm-svn: 62535
2009-01-19 22:00:18 +00:00
Chris Lattner
b88febb5cd Fix PR3353, infinitely jump threading an infinite loop make from switches.
llvm-svn: 62529
2009-01-19 21:20:34 +00:00
Bill Wendling
bf83203ae6 Temporarily revert r62487. It's causing this error during a release bootstrap of
llvm-gcc. Most likely, it's miscompiling one of the "gen*" programs:

/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm-gcc.obj/./prev-gcc/xgcc -B/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm-gcc.obj/./prev-gcc/ -B/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm-gcc.install/i386-apple-darwin9.6.0/bin/ -c -g -O2 -mdynamic-no-pic -DIN_GCC -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -mdynamic-no-pic -DHAVE_CONFIG_H -DGENERATOR_FILE -I. -Ibuild -I../../llvm-gcc.src/gcc -I../../llvm-gcc.src/gcc/build -I../../llvm-gcc.src/gcc/../include -I./../intl -I../../llvm-gcc.src/gcc/../libcpp/include  -I../../llvm-gcc.src/gcc/../libdecnumber -I../libdecnumber -I/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.obj/include -I/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/include -DENABLE_LLVM -I/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.obj/../llvm.src/include  -D_DEBUG  -D_GNU_SOURCE -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS   -o build/gencondmd.o build/gencondmd.c
../../llvm-gcc.src/gcc/config/i386/mmx.md:926: error: expected '}' before ')' token
../../llvm-gcc.src/gcc/config/i386/mmx.md:926: warning: excess elements in struct initializer
../../llvm-gcc.src/gcc/config/i386/mmx.md:926: warning: (near initialization for 'insn_conditions[4]')
../../llvm-gcc.src/gcc/config/i386/mmx.md:926: error: expected '}' before ')' token
../../llvm-gcc.src/gcc/config/i386/mmx.md:926: error: expected ',' or ';' before ')' token
../../llvm-gcc.src/gcc/config/i386/mmx.md:927: error: expected identifier or '(' before ',' token
../../llvm-gcc.src/gcc/config/i386/sse.md:3458: error: expected identifier or '(' before ',' token
...

llvm-svn: 62506
2009-01-19 08:46:20 +00:00
Chris Lattner
bb76cc9447 Fix PR3016, a bug which can occur do to an invalid assumption:
we assumed a CFG structure that would be valid when all code in 
the function is reachable, but not all code is necessarily 
reachable.  Do a simple, but horrible, CFG walk to check for this
case.

llvm-svn: 62487
2009-01-19 02:46:28 +00:00
Chris Lattner
af6f58bbf4 reduce indentation by using 'continue', no functionality change.
llvm-svn: 62477
2009-01-19 02:07:32 +00:00
Chris Lattner
c03b442e54 Fix some problems in SpeculativelyExecuteBB. Basically,
because of dead code, a phi could use the speculated instruction
that was not in "BB2".  Make this check explicit and tighten up 
some other corners.  This fixes PR3292.  No testcase becauase this
depends entirely on visitation order of blocks and requires a 
sequence of 8 passes to repro.

llvm-svn: 62476
2009-01-19 00:36:37 +00:00
Chris Lattner
ead19aaccb Make this a bit more explicit about which cases need the
check.  No functionality change.

llvm-svn: 62474
2009-01-18 23:22:07 +00:00
Chris Lattner
6f03811071 Fix rdar://6505632, an llc crash on 483.xalancbmk
llvm-svn: 62470
2009-01-18 20:35:00 +00:00
Duncan Sands
ddfeabbab7 BasicAliasAnalysis and FunctionAttrs were both
doing very similar pointer capture analysis.
Factor out the common logic.  The new version
is from FunctionAttrs since it does a better
job than the version in BasicAliasAnalysis

llvm-svn: 62461
2009-01-18 12:19:30 +00:00
Nick Lewycky
39fcb513ca Fix copy and pasted typos that prevented strtok_r, realloc, getenv, ungetc,
putc, puts, perror, vscanf and vsscanf from getting annotations.

Add annotations for eight printf functions, memalign, pread and pwrite.

On Linux, llvm-gcc sometimes renames strdup, getc, putc, strtok_r, scanf and
sscanf. Match the alternate function names.

Fix a crash annotating opendir.

Don't mark fsetpos's second parameter as nocapture. It's supposed to be
captured.

Do mark fopen's path and mode strings as nocapture. Mark ferror as readonly,
but not fileno which may set errno.

llvm-svn: 62456
2009-01-18 04:34:36 +00:00
Gabor Greif
20f36c51bd introduce typedef for complicated vector, and use it too
llvm-svn: 62384
2009-01-17 00:09:08 +00:00
Gabor Greif
0d0908d06a typo
llvm-svn: 62377
2009-01-16 23:08:50 +00:00
Chris Lattner
5d1ed9ed1f Fix PR3335 by not turning a store to one address space into a store to another.
llvm-svn: 62351
2009-01-16 20:12:52 +00:00
Chris Lattner
59dfd7d4af reduce indentation by using early exits, no functionality change.
llvm-svn: 62350
2009-01-16 20:08:59 +00:00
Evan Cheng
e7c9310d1b Clean up previous cast optimization a bit. Also make zext elimination a bit more aggressive: if it's not necessary to emit an AND (i.e. high bits are already zero), it's profitable to evaluate the operand at a different type.
llvm-svn: 62297
2009-01-16 02:11:43 +00:00
Rafael Espindola
0aba6c9435 Add the private linkage.
llvm-svn: 62279
2009-01-15 20:18:42 +00:00
Gabor Greif
b1f92de36f avoid using iterators when they get invalidated potentially
this fixes PR3332

llvm-svn: 62271
2009-01-15 18:40:09 +00:00
Evan Cheng
340e5fe0a6 Eliminate a redundant check.
llvm-svn: 62264
2009-01-15 17:09:07 +00:00
Evan Cheng
d504f9fe27 - Teach CanEvaluateInDifferentType of this xform: sext (zext ty1), ty2 -> zext ty2
- Looking at the number of sign bits of the a sext instruction to determine  whether new trunc + sext pair should be added when its source is being evaluated in a different type.

llvm-svn: 62263
2009-01-15 17:01:23 +00:00
Chris Lattner
fa0c0e19f6 Fix PR3325, a miscompilation of invokes by IPSCCP. Patch by Jay Foad!
llvm-svn: 62244
2009-01-14 21:01:16 +00:00
Dale Johannesen
816f9bc81d Fix the time regression I introduced in 464.h264ref with
my earlier patch to this file.

The issue there was that all uses of an IV inside a loop
are actually references to Base[IV*2], and there was one
use outside that was the same but LSR didn't see the base
or the scaling because it didn't recurse into uses outside
the loop; thus, it used base+IV*scale mode inside the loop
instead of pulling base out of the loop.  This was extra bad
because register pressure later forced both base and IV into
memory.  Doing that recursion, at least enough
to figure out addressing modes, is a good idea in general;
the change in AddUsersIfInteresting does this.  However,
there were side effects....

It is also possible for recursing outside the loop to
introduce another IV where there was only 1 before (if
the refs inside are not scaled and the ref outside is).
I don't think this is a common case, but it's in the testsuite.
It is right to be very aggressive about getting rid of
such introduced IVs (CheckForIVReuse and the handling of
nonzero RewriteFactor in StrengthReduceStridedIVUsers).
In the testcase in question the new IV produced this way
has both a nonconstant stride and a nonzero base, neither
of which was handled before.  And when inserting 
new code that feeds into a PHI, it's right to put such 
code at the original location rather than in the PHI's 
immediate predecessor(s) when the original location is outside 
the loop (a case that couldn't happen before)
(RewriteInstructionToUseNewBase); better to avoid making
multiple copies of it in this case.

Also, the mechanism for keeping SCEV's corresponding to GEP's
no longer works, as the GEP might change after its SCEV
is remembered, invalidating the SCEV, and we might get a bad
SCEV value when looking up the GEP again for a later loop.  
This also couldn't happen before, as we weren't recursing
into GEP's outside the loop.

Also, when we build an expression that involves a (possibly
non-affine) IV from a different loop as well as an IV from
the one we're interested in (containsAddRecFromDifferentLoop),
don't recurse into that.  We can't do much with it and will
get in trouble if we try to create new non-affine IVs or something.

More testcases are coming.

llvm-svn: 62212
2009-01-14 02:35:31 +00:00