29bc8a91d3
Teach basicaa that x|c == x+c when the c bits of x are clear. This
...
allows us to compile the example in readme.txt into:
LBB1_1: ## %bb
movl 4(%rdx,%rax), %ecx
movl %ecx, %esi
imull (%rdx,%rax), %esi
imull %esi, %ecx
movl %esi, 8(%rdx,%rax)
imull %ecx, %esi
movl %ecx, 12(%rdx,%rax)
movl %esi, 16(%rdx,%rax)
imull %ecx, %esi
movl %esi, 20(%rdx,%rax)
addq $16, %rax
cmpq $4000, %rax
jne LBB1_1
instead of:
LBB1_1:
movl (%rdx,%rax), %ecx
imull 4(%rdx,%rax), %ecx
movl %ecx, 8(%rdx,%rax)
imull 4(%rdx,%rax), %ecx
movl %ecx, 12(%rdx,%rax)
imull 8(%rdx,%rax), %ecx
movl %ecx, 16(%rdx,%rax)
imull 12(%rdx,%rax), %ecx
movl %ecx, 20(%rdx,%rax)
addq $16, %rax
cmpq $4000, %rax
jne LBB1_1
GCC (4.2) doesn't seem to be able to eliminate the loads in this
testcase either, it generates:
L2:
movl (%rdx), %eax
imull 4(%rdx), %eax
movl %eax, 8(%rdx)
imull 4(%rdx), %eax
movl %eax, 12(%rdx)
imull 8(%rdx), %eax
movl %eax, 16(%rdx)
imull 12(%rdx), %eax
movl %eax, 20(%rdx)
addl $4, %ecx
addq $16, %rdx
cmpl $1002, %ecx
jne L2
llvm-svn: 89952
2009-11-26 16:26:43 +00:00
12dacdd359
teach basicaa that A[i] != A[i+1].
...
llvm-svn: 89951
2009-11-26 16:18:10 +00:00
7a5b56aca9
Change the other half of aliasGEP (which handles GEP differencing) to use DecomposeGEPExpression. This dramatically simplifies and shrinks the code by eliminating the horrible CheckGEPInstructions method, fixes a miscompilation ( @test3 ) and makes the code more aggressive. In particular, we now handle the @test4 case, which is reduced from the SmallPtrSet constructor. Missing this caused us to emit a variable length memset instead of a fixed size one.
...
llvm-svn: 89922
2009-11-26 02:17:34 +00:00
5341c9679d
Generalize DecomposeGEPExpression to exactly handle what Value::getUnderlyingObject does (when TD is around). This allows us to avoid calling DecomposeGEPExpression unless the ultimate alias check we care about passes, speedup up BasicAA a bit.
...
llvm-svn: 89920
2009-11-26 02:14:59 +00:00
8928899413
Implement a new DecomposeGEPExpression method, which decomposes a GEP into a list of scaled offsets. Use this to eliminate some previous ad-hoc code which was subtly broken (it assumed all Constant*'s were non-zero, but strange constant express could be zero).
...
llvm-svn: 89915
2009-11-26 02:13:03 +00:00
a99edbedd1
Use GEPOperator more pervasively to simplify code.
...
llvm-svn: 89914
2009-11-26 02:11:08 +00:00
214ef9a4ef
fix comment, thanks all :)
...
llvm-svn: 89666
2009-11-23 17:07:35 +00:00
1e7b37ebba
use the new isNoAlias method to simplify some code, only do an escaping check if
...
we have a non-constant pointer. Constant pointers can't be local.
llvm-svn: 89665
2009-11-23 16:46:41 +00:00
98e25326a0
whitespace cleanup, tidying
...
llvm-svn: 89664
2009-11-23 16:45:27 +00:00
84ed59abcf
speed up BasicAA a bit by implementing a long-standing TODO.
...
llvm-svn: 89663
2009-11-23 16:44:43 +00:00
a13c9d1a5e
add fixme for dubious code. Duncan, what do you think?
...
llvm-svn: 89602
2009-11-22 16:16:48 +00:00
db1e9f1290
remove a silly condition that doesn't make a lot of sense anymore.
...
llvm-svn: 89601
2009-11-22 16:15:59 +00:00
d6a49ad25a
reduce indentation, no functionality change.
...
llvm-svn: 89600
2009-11-22 16:05:05 +00:00
88874ec60a
Remove the AliasAnalysis::getMustAliases method, which is dead.
...
The hasNoModRefInfoForCalls isn't worth it as a filter because
basicaa provides m/r info and everything chains to it, so remove
it.
llvm-svn: 89599
2009-11-22 16:01:44 +00:00
94e617627d
Extend CaptureTracking to indicate when a value is never stored, even
...
if it is not ultimately captured. Teach BasicAliasAnalysis that a
local object address which does not escape and is never stored does
not alias with a value resulting from a load.
llvm-svn: 89398
2009-11-19 21:57:48 +00:00
c53e2ecf02
Teach BasicAA that a constant expression can't alias memory provably not
...
allocated until runtime (such as an alloca). Patch by Hans Wennborg!
llvm-svn: 88760
2009-11-14 06:15:14 +00:00
ccb4584edd
Default-addressspace null pointers don't alias anything. This allows
...
GVN to be more aggressive. Patch by Hans Wennborg! (with a comment added by me)
llvm-svn: 86582
2009-11-09 19:29:11 +00:00
46b5c642b9
remove a bunch of extraneous LLVMContext arguments
...
from various APIs, addressing PR5325.
llvm-svn: 86231
2009-11-06 04:27:31 +00:00
f390e04a47
Rename MallocFreeHelper as MemoryBuiltins
...
llvm-svn: 85286
2009-10-27 20:05:49 +00:00
762195bd01
Rename MallocHelper as MallocFreeHelper, since it now also identifies calls to free()
...
llvm-svn: 85181
2009-10-26 23:58:56 +00:00
3b7ba5f35b
Teach BasicAA how to analyze Select instructions, and make it more
...
aggressive on PHI instructions.
llvm-svn: 85158
2009-10-26 21:55:43 +00:00
974e12b2d3
Remove includes of Support/Compiler.h that are no longer needed after the
...
VISIBILITY_HIDDEN removal.
llvm-svn: 85043
2009-10-25 06:57:41 +00:00
02d5f77d26
Remove VISIBILITY_HIDDEN from class/struct found inside anonymous namespaces.
...
Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit.
llvm-svn: 85042
2009-10-25 06:33:48 +00:00
8acf2956b8
Remove AllocationInst. Since MallocInst went away, AllocaInst is the only subclass of AllocationInst, so it no longer is necessary.
...
llvm-svn: 84969
2009-10-23 21:09:37 +00:00
b2647b9e67
inline isGEP away.
...
llvm-svn: 84373
2009-10-17 23:48:54 +00:00
8ec25937f1
When checking aliases between phi sources and V2, we know the sources are not themselves phi nodes. However, V2 may be. Call aliasCheck with V2 first to potentially eliminate a std::swap call.
...
llvm-svn: 84226
2009-10-16 00:33:09 +00:00
d708a4908c
Add missing break statements! Thanks to Duncan Sands for pointing this out!
...
llvm-svn: 84191
2009-10-15 18:48:58 +00:00
9cec2380f2
Teach basicaa about memcpy/memmove/memset. The length argument can be used to
...
improve alias results if constant, and the source pointer can't be modified.
llvm-svn: 84175
2009-10-15 07:11:24 +00:00
d7216cf74c
Teach BasicAA to use the size parameter of the memory use marker intrinsics.
...
llvm-svn: 84174
2009-10-15 06:12:11 +00:00
fcb27ad54c
Take advantage of TargetData when available; we know that the atomic intrinsics
...
only dereference the element they point to directly with no pointer arithmetic.
llvm-svn: 84159
2009-10-15 00:36:35 +00:00
b3ccb6498c
Clear VisitedPHIs after use.
...
llvm-svn: 84080
2009-10-14 06:46:26 +00:00
c1eed9d120
Another BasicAA fix. If a value does not alias a GEP's base pointer, then it
...
cannot alias the GEP. GEP pointer alias rule states this clearly:
A pointer value formed from a getelementptr instruction is associated with the
addresses associated with the first operand of the getelementptr.
llvm-svn: 84079
2009-10-14 06:41:49 +00:00
f92f5557ee
More code clean up based on patch feedback.
...
llvm-svn: 84074
2009-10-14 05:22:03 +00:00
31565b3e9f
Change VisitedPHIs into an instance variable that's freed by each alias() call.
...
llvm-svn: 84072
2009-10-14 05:05:02 +00:00
c10e88db22
Teach basic AA about PHI nodes. If all operands of a phi NoAlias another value than it's safe to declare the PHI NoAlias the value. Ditto for MustAlias.
...
llvm-svn: 84038
2009-10-13 22:02:20 +00:00
f1f3dd3c3c
Refactor some code. No functionality changes.
...
llvm-svn: 84000
2009-10-13 18:42:04 +00:00
e2782c7614
Teach BasicAA a little something about the atomic intrinsics: they can only
...
modify through the pointer they're given.
llvm-svn: 83959
2009-10-13 07:48:38 +00:00
537d8d99be
Enhance analysis passes so that they apply the same analysis to malloc calls as to MallocInst.
...
Reviewed by Eli Friedman.
llvm-svn: 82281
2009-09-18 21:34:51 +00:00
bc1d841a63
Use stripPointerCasts instead of doing the same manually.
...
llvm-svn: 80267
2009-08-27 18:02:03 +00:00
55f1c09e31
Push LLVMContexts through the IntegerType APIs.
...
llvm-svn: 78948
2009-08-13 21:58:54 +00:00
5a1acd9912
Move a few more APIs back to 2.5 forms. The only remaining ones left to change back are
...
metadata related, which I'm waiting on to avoid conflicting with Devang.
llvm-svn: 77721
2009-07-31 20:28:14 +00:00
487375e9a2
Move ConstantExpr to 2.5 API.
...
llvm-svn: 77494
2009-07-29 18:55:55 +00:00
43d19d61d4
Make AliasAnalysis and related classes use
...
getAnalysisIfAvailable<TargetData>().
llvm-svn: 77028
2009-07-25 00:48:42 +00:00
edb4a70325
Revert the ConstantInt constructors back to their 2.5 forms where possible, thanks to contexts-on-types. More to come.
...
llvm-svn: 77011
2009-07-24 23:12:02 +00:00
47db941fd3
Get rid of the Pass+Context magic.
...
llvm-svn: 76702
2009-07-22 00:24:57 +00:00
33a3fd0b9c
Revert the addition of hasNoPointerOverflow to GEPOperator.
...
Getelementptrs that are defined to wrap are virtually useless to
optimization, and getelementptrs that are undefined on any kind
of overflow are too restrictive -- it's difficult to ensure that
all intermediate addresses are within bounds. I'm going to take
a different approach.
Remove a few optimizations that depended on this flag.
llvm-svn: 76437
2009-07-20 17:43:30 +00:00
1d548d851a
Make BasicAliasAnalysis and Value::getUnderlyingObject use
...
GEPOperator's hasNoPointer0verflow(), and make a few places in instcombine
that create GEPs that may overflow clear the NoOverflow value. Among
other things, this partially addresses PR2831.
llvm-svn: 76252
2009-07-17 22:25:10 +00:00
20b34ac794
Move the ConstantInt uniquing table into LLVMContextImpl. This exposed a number of issues in
...
our current context-passing stuff, which is also fixed here
llvm-svn: 76089
2009-07-16 18:04:31 +00:00
fbcc663cbf
llvm_unreachable->llvm_unreachable(0), LLVM_UNREACHABLE->llvm_unreachable.
...
This adds location info for all llvm_unreachable calls (which is a macro now) in
!NDEBUG builds.
In NDEBUG builds location info and the message is off (it only prints
"UREACHABLE executed").
llvm-svn: 75640
2009-07-14 16:55:14 +00:00
56d0659726
assert(0) -> LLVM_UNREACHABLE.
...
Make llvm_unreachable take an optional string, thus moving the cerr<< out of
line.
LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for
NDEBUG builds.
llvm-svn: 75379
2009-07-11 20:10:48 +00:00
38264b1554
"LLVMContext* " --> "LLVMContext *"
...
llvm-svn: 74878
2009-07-06 23:00:19 +00:00
39f00cc1d4
Thread LLVMContext through the constant folding APIs, which touches a lot of files.
...
llvm-svn: 74844
2009-07-06 18:42:36 +00:00
e9454e8c25
Remove unneeded #include.
...
llvm-svn: 73911
2009-06-22 22:09:07 +00:00
776e4c8d35
Teach BasicAliasAnalysis to understand constant gep indices that fall
...
beyond their associated static array type.
I believe that this fixes a legitimate bug, because BasicAliasAnalysis
already has code to check for this condition that works for non-constant
indices, however it was missing the case of constant indices. With this
change, it checks for both.
This fixes PR4267, and miscompiles of SPEC 188.ammp and 464.h264.href.
llvm-svn: 72451
2009-05-27 01:48:27 +00:00
af9eaa830a
Rename PaddedSize to AllocSize, in the hope that this
...
will make it more obvious what it represents, and stop
it being confused with the StoreSize.
llvm-svn: 71349
2009-05-09 07:06:46 +00:00
73247d2edc
Generalize some alias analysis logic from atomic
...
intrinsics to any IntrWriteArgMem intrinsics.
llvm-svn: 64551
2009-02-14 10:56:35 +00:00
c60bd012bc
BasicAA was making the assumption that a local allocation which hadn't escaped
...
couldn't ever be the return of call instruction. However, it's quite possible
that said local allocation is itself the return of a function call. That's
what malloc and calloc are for, actually.
llvm-svn: 64442
2009-02-13 07:06:27 +00:00
98a3617fba
Refactor my previous change to maintain the distinction between AliasAnalysis and BasicAliasAnalysis. This involves some wider changes because it
...
folds away some never-used methods.
llvm-svn: 63900
2009-02-05 23:36:27 +00:00
1caf7fef8e
Finish making AliasAnalysis aware of the fact that most atomic intrinsics only dereference their arguments, and enhance
...
BasicAA to make use of this fact when computing ModRef info.
llvm-svn: 63718
2009-02-04 05:16:46 +00:00
fb306c0a10
Move isIdentifiedObject and isNoAliasCall into AliasAnalysis.cpp since
...
they are useful to analyses other than BasicAliasAnalysis.cpp. Include
the full comment for isIdentifiedObject in the header file. Thanks to
Chris for suggeseting this.
llvm-svn: 63589
2009-02-03 01:28:32 +00:00
1ee0d41ef8
Fix a post-RA scheduling dependency bug.
...
If a MachineInstr doesn't have a memoperand but has an opcode that
is known to load or store, assume its memory reference may alias
*anything*, including stack slots which the compiler completely
controls.
To partially compensate for this, teach the ScheduleDAG building
code to do basic getUnderlyingValue analysis. This greatly
reduces the number of instructions that require restrictive
dependencies. This code will need to be revisited when we start
doing real alias analysis, but it should suffice for now.
llvm-svn: 63370
2009-01-30 02:49:14 +00:00
e0aa0d677d
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
1b94d420ae
add a comment
...
llvm-svn: 62436
2009-01-18 00:27:21 +00:00
dc020f9c3c
Rename getABITypeSize to getTypePaddedSize, as
...
suggested by Chris.
llvm-svn: 62099
2009-01-12 20:38:59 +00:00
2089cd09ba
make tblgen autogenerate the nocapture intrinsics for
...
llvm.memcpy/memset/memmove. This allows removal of some
hackish code from basicaa.
llvm-svn: 62071
2009-01-12 02:41:37 +00:00
8d65f3690e
When checking if an Argument escapes, check if
...
the argument is marked nocapture - no need to
analyze the argument if the answer is already
known!
llvm-svn: 61753
2009-01-05 21:19:53 +00:00
2abb108f1b
Resubmit support for the 'nocapture' attribute.
...
The problematic part of this patch is that we were out of attribute bits,
requiring some fancy bit hacking to make it fit (by shrinking alignment)
without breaking existing users or the file format.
This change will require users to rebuild llvm-gcc to match llvm.
llvm-svn: 61239
2008-12-19 06:39:12 +00:00
a397baea88
Temporarily revert r61019, r61030, and r61040. These were breaking LLVM Release
...
builds.
llvm-svn: 61094
2008-12-16 19:06:48 +00:00
e3401db1f3
Teach basicaa to use the nocapture attribute when possible. When the
...
intrinsics are properly marked nocapture, the fixme should be addressed.
llvm-svn: 61040
2008-12-15 18:59:22 +00:00
2e84a548d6
Allow basicaa to walk through geps with identical indices in
...
parallel, allowing it to decide that P/Q must alias if A/B
must alias in things like:
P = gep A, 0, i, 1
Q = gep B, 0, i, 1
This allows GVN to delete 62 more instructions out of 403.gcc.
llvm-svn: 60820
2008-12-10 01:04:47 +00:00
702e46ed54
Teach BasicAA::getModRefInfo(CallSite, CallSite) some
...
tricks based on readnone/readonly functions.
Teach memdep to look past readonly calls when analyzing
deps for a readonly call. This allows elimination of a
few more calls from 403.gcc:
before:
63 gvn - Number of instructions PRE'd
153986 gvn - Number of instructions deleted
50069 gvn - Number of loads deleted
after:
63 gvn - Number of instructions PRE'd
153991 gvn - Number of instructions deleted
50069 gvn - Number of loads deleted
5 calls isn't much, but this adds plumbing for the next change.
llvm-svn: 60794
2008-12-09 21:19:42 +00:00
714ffa36d3
Fix comment typo.
...
llvm-svn: 60697
2008-12-08 14:01:59 +00:00
2f9d8458c8
Some minor optimizations for isObjectSmallerThan.
...
llvm-svn: 60687
2008-12-08 06:28:54 +00:00
d59572cb22
Seriously strengthen the guarantee offered by noalias on a function's return
...
value. It must now be as if the pointer were allocated and has not escaped to
the caller. Thanks to Dan Gohman for pointing out the error in the original
and helping devise this definition.
llvm-svn: 59940
2008-11-24 05:00:44 +00:00
f5ffcbcd0b
Extend the 'noalias' attribute to function return values. This is intended to
...
indicate functions that allocate, such as operator new, or list::insert. The
actual definition is slightly less strict (for now).
No changes to the bitcode reader/writer, asm printer or verifier were needed.
llvm-svn: 59934
2008-11-24 03:41:24 +00:00
d65a4daeea
Factorize code: remove variants of "strip off
...
pointer bitcasts and GEP's", and centralize the
logic in Value::getUnderlyingObject. The
difference with stripPointerCasts is that
stripPointerCasts only strips GEPs if all
indices are zero, while getUnderlyingObject
strips GEPs no matter what the indices are.
llvm-svn: 56922
2008-10-01 15:25:41 +00:00
ba3fa6c6e1
s/ParameterAttributes/Attributes/g
...
llvm-svn: 56513
2008-09-23 23:03:40 +00:00
a79db30d28
Tidy up several unbeseeming casts from pointer to intptr_t.
...
llvm-svn: 55779
2008-09-04 17:05:41 +00:00
fb46605e47
simplify some code by using a helper function. This really really
...
wants a 'nocapture' predicate.
llvm-svn: 52304
2008-06-16 06:38:26 +00:00
2d33297d00
move a bunch of predicates up into their own section
...
in this file, no other changes.
llvm-svn: 52303
2008-06-16 06:30:22 +00:00
fa48258a61
Other parts of this code treat noalias arguments as objects for
...
the purposes of escape analysis.
llvm-svn: 52302
2008-06-16 06:28:01 +00:00
b35d9b5e07
If we are checking to see if the result of a call aliases a
...
pointer derived from a local allocation, if the local allocation
never escapes, the pointers can't alias. This implements PR2436
llvm-svn: 52301
2008-06-16 06:19:11 +00:00
98ad816f58
Refactor basicaa's main alias function somethin' fierce.
...
This fixes several minor bugs (such as returning noalias
for comparisons between external weak functions an null) but
is mostly a cleanup.
llvm-svn: 52299
2008-06-16 06:10:11 +00:00
416867a81b
Fixes PR2395. Looking for a constant in a GEP tail (when the first GEP
...
is longer than the second one) should stop after finding one. Added break
instruction guarantees it. It also changes difference between offsets to
absolute value of this difference in the condition.
llvm-svn: 51875
2008-06-02 17:26:12 +00:00
d78c400b5b
Clean up the use of static and anonymous namespaces. This turned up
...
several things that were neither in an anonymous namespace nor static
but not intended to be global.
llvm-svn: 51017
2008-05-13 00:00:25 +00:00
5429033c03
Fix a "large integer implicitly truncated to unsigned type"
...
warning.
llvm-svn: 50033
2008-04-21 07:35:28 +00:00
8fc8a272e0
Don't assume a tail call can't reference a byval
...
argument to the outer function, this isn't correct.
llvm-svn: 49731
2008-04-15 17:41:34 +00:00
80e43fa744
Restore isCFGOnly property of various analysis passes.
...
llvm-svn: 48579
2008-03-20 02:25:21 +00:00
718da668ab
PassInfo keep tracks whether a pass is an analysis pass or not.
...
llvm-svn: 48554
2008-03-19 21:56:59 +00:00
eec73618af
Fix a compiler warning.
...
llvm-svn: 47328
2008-02-19 09:28:48 +00:00
d2d7c6b309
In addition to arguments passed to it, memcpy (and all other calls) can ModRef pointers that alias their arguments as well. This fixes PR2057.
...
llvm-svn: 47317
2008-02-19 06:47:18 +00:00
8ed77c41d8
don't bother calling getUnderlyingObject for non-pointers.
...
llvm-svn: 47272
2008-02-18 17:28:21 +00:00
cc01ebbac6
Since we're not checking for the more general AllocationInst first, we need to explicitly check
...
that Object is an Argument before casting it to one.
llvm-svn: 47268
2008-02-18 10:11:00 +00:00
bdf7ed9495
This check is not correct for mallocs, so exclude them earlier.
...
llvm-svn: 47263
2008-02-18 09:11:02 +00:00
57a98b7f4b
Fix a comment, and a bug where we weren't applying the tail call logic in cases that failed the first test.
...
llvm-svn: 47253
2008-02-18 03:52:21 +00:00
fa2ba5352f
Fix bugs that Chris noticed in my last patch.
...
llvm-svn: 47252
2008-02-18 02:31:23 +00:00
8432cc662f
bitcasts of pointers are always pointers.
...
If we see a memcpy of a pointer, make sure to check later
uses of the pointer as well.
llvm-svn: 47250
2008-02-18 02:11:28 +00:00
2e3edf193a
Teach getModRefInfo that memcpy, memmove, and memset don't "capture" memory addresses.
...
Also, noalias arguments are be considered "like" stack allocated ones for this purpose, because
the only way they can be modref'ed is if they escape somewhere in the current function.
llvm-svn: 47247
2008-02-17 21:29:08 +00:00
23dd05514e
getUnderlyingObject can return null, handle this.
...
llvm-svn: 46318
2008-01-24 19:07:10 +00:00
9104d71269
Teach basicaa that 'byval' arguments define a new memory location that
...
can't be aliased to other known objects. This allows us to know that byval
pointer args don't alias globals, etc.
llvm-svn: 46315
2008-01-24 18:00:32 +00:00
Chris Lattner