Commit Graph

320 Commits

Author SHA1 Message Date
Gabor Greif 9d5ae03404 cache result of operator*
llvm-svn: 107990
2010-07-09 16:51:20 +00:00
Gabor Greif 218f5541b2 use ArgOperand API and CallSite for arg range; add necessary casts and perform some cosmetics
llvm-svn: 106747
2010-06-24 14:42:01 +00:00
Gabor Greif 27b3d55194 use abstract accessors to CallInst
llvm-svn: 101899
2010-04-20 13:13:04 +00:00
Eric Christopher 7258dcd77f Revert 101465, it broke internal OpenGL testing.
Probably the best way to know that all getOperand() calls have been handled
is to replace that API instead of updating.

llvm-svn: 101579
2010-04-16 23:37:20 +00:00
Gabor Greif f375520f7b reapply r101434
with a fix for self-hosting

rotate CallInst operands, i.e. move callee to the back
of the operand array

the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary

llvm-svn: 101465
2010-04-16 15:33:14 +00:00
Gabor Greif 403e9694f9 back out r101423 and r101397, they break llvm-gcc self-host on darwin10
llvm-svn: 101434
2010-04-16 01:16:20 +00:00
Gabor Greif 33ae80bff7 reapply r101364, which has been backed out in r101368
with a fix

rotate CallInst operands, i.e. move callee to the back
of the operand array

the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary

llvm-svn: 101397
2010-04-15 20:51:13 +00:00
Gabor Greif 9fd00c7d25 back out r101364, as it trips the linux nightlybot on some clang C++ tests
llvm-svn: 101368
2010-04-15 12:46:56 +00:00
Gabor Greif aafd209632 rotate CallInst operands, i.e. move callee to the back
of the operand array

the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary

llvm-svn: 101364
2010-04-15 10:49:53 +00:00
Evan Cheng 21b588b678 - Code clean up to reduce indentation.
- TryToOptimizeStoreOfMallocToGlobal should check if TargetData is available and bail out if it is not. The transformations being done requires TD.

llvm-svn: 101285
2010-04-14 20:52:55 +00:00
Chris Lattner b9801ffcb5 fix PR6760, a missing check in heap SRoA.
llvm-svn: 100936
2010-04-10 18:19:22 +00:00
Gabor Greif 08d85da6cc fix 80-col violations
llvm-svn: 100677
2010-04-07 18:59:26 +00:00
Gabor Greif 679728790b make more two predicates constant
llvm-svn: 100549
2010-04-06 19:24:18 +00:00
Gabor Greif 08355d6cda performance: get rid of repeated dereferencing of use_iterator by caching its result
llvm-svn: 100547
2010-04-06 19:14:05 +00:00
Gabor Greif a21bc0fbd5 const-ize predicate ValueIsOnlyUsedLocallyOrStoredToOneGlobal
llvm-svn: 100546
2010-04-06 18:58:22 +00:00
Gabor Greif 0439789023 use CallSite to access calls vs. invokes uniformly
and remove assumptions about operand order

llvm-svn: 100544
2010-04-06 18:45:08 +00:00
Dan Gohman 4bd755419f Revert the recent alignment changes. They're broken for -Os because,
in particular, they end up aligning strings at 16-byte boundaries, and
there's no way for GlobalOpt to check OptForSize.

llvm-svn: 100172
2010-04-02 03:04:37 +00:00
Dan Gohman c671347fcb Make globalopt refine global variable alignment.
llvm-svn: 100160
2010-04-02 00:14:16 +00:00
Gabor Greif 5d5db5342b Introduce ImmutableCallSite, useful for contexts where no mutation
is necessary. Inherits from new templated baseclass CallSiteBase<>
which is highly customizable. Base CallSite on it too, in a configuration
that allows full mutation.
Adapt some call sites in analyses to employ ImmutableCallSite.

llvm-svn: 100100
2010-04-01 08:21:08 +00:00
Gabor Greif febf6ab718 Add a setCalledFunction member to InvokeInst (like in CallInst)
and use this (as well as getCalledValue) to access the callee,
instead of {g|s}etOperand(0).

llvm-svn: 99084
2010-03-20 21:00:25 +00:00
Chris Lattner 65d3a0a5f8 Fix rdar://7694996 a miscompile of 183.equake from my patch yesterday,
confusing the old MAT variable with the new GlobalType one.  This caused
us to promote the @disp global pointer into:

@disp.body = internal global double*** undef

instead of:

@disp.body = internal global [3 x double**] undef

llvm-svn: 97285
2010-02-26 23:42:13 +00:00
Chris Lattner da5fcdace0 remove dead code, by this point all uses of CI are gone.
llvm-svn: 97283
2010-02-26 23:35:25 +00:00
Chris Lattner 0521c09d97 fix PR6435 another bug from the MallocInst elimination work.
llvm-svn: 97231
2010-02-26 18:23:13 +00:00
Chris Lattner 7939f795f5 rewrite OptimizeGlobalAddressOfMalloc to fix PR6422, some bugs
introduced when mallocinst was eliminated. 

llvm-svn: 97178
2010-02-25 22:33:52 +00:00
Nick Lewycky 614fb949b9 Modernize comment.
llvm-svn: 97121
2010-02-25 06:39:10 +00:00
Duncan Sands 19d0b47b1f There are two ways of checking for a given type, for example isa<PointerType>(T)
and T->isPointerTy().  Convert most instances of the first form to the second form.
Requested by Chris.

llvm-svn: 96344
2010-02-16 11:11:14 +00:00
Duncan Sands 9dff9bec31 Uniformize the names of type predicates: rather than having isFloatTy and
isInteger, we now have isFloatTy and isIntegerTy.  Requested by Chris!

llvm-svn: 96223
2010-02-15 16:12:20 +00:00
Jakob Stoklund Olesen e27dc727e2 Keep iterating over all uses when meeting a phi node in AllUsesOfValueWillTrapIfNull().
This bug was exposed by my inliner cost changes in r94615, and caused failures
of lencod on most architectures when building with LTO.

This patch fixes lencod and 464.h264ref on x86-64 (and likely others).

llvm-svn: 94858
2010-01-29 23:54:14 +00:00
Chris Lattner 9855a6bb7c handle ConstantVector while I'm in here.
llvm-svn: 92892
2010-01-07 01:20:20 +00:00
Chris Lattner 64ecc468bd fix a globalopt crash on 'bullet' (handling evaluation of a store
to an element of a vector in a static ctor) which occurs with an 
unrelated patch I'm testing.  Annoyingly, EvaluateStoreInto basically 
does exactly the same stuff as InsertElement constant folding, but it
now handles vectors, and you can't insertelement into a vector.  It
would be 'really nice' if GEP into a vector were not legal.

llvm-svn: 92889
2010-01-07 01:16:21 +00:00
Benjamin Kramer d2564e3afb Move remaining stuff to the isInteger predicate.
llvm-svn: 92771
2010-01-05 21:05:54 +00:00
Benjamin Kramer ccce8bae14 Avoid going through the LLVMContext for type equality where it's safe to dereference the type pointer.
llvm-svn: 92726
2010-01-05 13:12:22 +00:00
David Greene 44cb8ade45 Change errs() to dbgs().
llvm-svn: 92629
2010-01-05 01:28:05 +00:00
Duncan Sands 6a3df7b0c7 Teach GlobalOpt to delete aliases with internal linkage (after
forwarding any uses).  GlobalDCE can also do this, but is only
run at -O3.

llvm-svn: 90850
2009-12-08 10:10:20 +00:00
Dan Gohman 580b80d6d9 Make ConstantFoldConstantExpression recursively visit the entire
ConstantExpr, not just the top-level operator. This allows it to
fold many more constants.

Also, make GlobalOpt call ConstantFoldConstantExpression on
GlobalVariable initializers.

llvm-svn: 89659
2009-11-23 16:22:21 +00:00
Victor Hernandez fcc77b1c02 Update computeArraySize() to use ComputeMultiple() to determine the array size associated with a malloc; also extend PerformHeapAllocSRoA() to check if the optimized malloc's arg had its highest bit set, so that it is safe for ComputeMultiple() to look through sext instructions while determining the optimized malloc's array size
llvm-svn: 86676
2009-11-10 08:32:25 +00:00
Victor Hernandez bde558c536 - new SROA mallocs should have the mallocs running-or'ed, not the malloc's bitcast
- fix ProcessInternalGlobal() debug output

llvm-svn: 86317
2009-11-07 00:41:19 +00:00
Victor Hernandez f3db915294 Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions.
Here is the original commit message:

This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments.

Update CreateMalloc so that its callers specify the size to allocate:
MallocInst-autoupgrade users use non-TargetData-computed allocation sizes.
Optimization uses use TargetData to compute the allocation size.

Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays.
Extend getMallocType() to support malloc calls that have non-bitcast uses.

Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses.  The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly.

Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses.  The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use.

Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use.

Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes.

llvm-svn: 86311
2009-11-07 00:16:28 +00:00
Chris Lattner 46b5c642b9 remove a bunch of extraneous LLVMContext arguments
from various APIs, addressing PR5325.

llvm-svn: 86231
2009-11-06 04:27:31 +00:00
Victor Hernandez b9f5899779 Revert r86077 because it caused crashes in 179.art and 175.vpr on ARM
llvm-svn: 86213
2009-11-06 01:33:24 +00:00
Victor Hernandez 492ed30a32 Update CreateMalloc so that its callers specify the size to allocate:
MallocInst-autoupgrade users use non-TargetData-computed allocation sizes.
Optimization uses use TargetData to compute the allocation size.

Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays.
Extend getMallocType() to support malloc calls that have non-bitcast uses.

Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses.  The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly.

Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses.  The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use.

Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use.

Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes.

llvm-svn: 86077
2009-11-05 00:03:03 +00:00
Chris Lattner b5d9c8c708 cleanups, switch GlobalDCE to SmallPtrSet instead of std::set
llvm-svn: 85730
2009-11-01 19:03:42 +00:00
Chris Lattner aa99c94e2a Revert 85678/85680. The decision is to stay with the current form of
indirectbr, thus we don't need "blockaddr(@func, null)".  Eliminate it
for simplicity.

llvm-svn: 85699
2009-11-01 01:27:45 +00:00
Chris Lattner 3c89c53f35 adjust a couple xforms to work with null bb's in BlockAddress.
llvm-svn: 85680
2009-10-31 20:13:24 +00:00
Chris Lattner 312748848f just for the hell of it, allow globalopt to statically evaluate
static constructors with indirect gotos :)

llvm-svn: 85495
2009-10-29 05:51:50 +00:00
Victor Hernandez 0d025421cd Extend getMallocArraySize() to determine the array size if the malloc argument is:
ArraySize * ElementSize
ElementSize * ArraySize
ArraySize << log2(ElementSize)
ElementSize << log2(ArraySize)

Refactor isArrayMallocHelper and delete isSafeToGetMallocArraySize, so that there is only 1 copy of the malloc array determining logic.
Update users of getMallocArraySize() to not bother calling isArrayMalloc() as well.

llvm-svn: 85421
2009-10-28 20:18:55 +00:00
Victor Hernandez f390e04a47 Rename MallocFreeHelper as MemoryBuiltins
llvm-svn: 85286
2009-10-27 20:05:49 +00:00
Victor Hernandez 762195bd01 Rename MallocHelper as MallocFreeHelper, since it now also identifies calls to free()
llvm-svn: 85181
2009-10-26 23:58:56 +00:00
Nick Lewycky 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
Nick Lewycky 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
Victor Hernandez e297149e26 Auto-upgrade free instructions to calls to the builtin free function.
Update all analysis passes and transforms to treat free calls just like FreeInst.
Remove RaiseAllocations and all its tests since FreeInst no longer needs to be raised.

llvm-svn: 84987
2009-10-24 04:23:03 +00:00
Victor Hernandez a3aaf85e23 Remove MallocInst from LLVM Instructions.
llvm-svn: 84299
2009-10-17 01:18:07 +00:00
Victor Hernandez 264da3274e HeapAllocSRoA also needs to check if malloc array size can be computed.
llvm-svn: 84288
2009-10-16 23:12:25 +00:00
Victor Hernandez 13020b1faf Fix bug where array malloc with unexpected computation of the size argument resulted in MallocHelper
identifying the malloc as a non-array malloc.  This broke GlobalOpt's optimization of stores of mallocs 
to global variables.

The fix is to classify malloc's into 3 categories:
1. non-array mallocs
2. array mallocs whose array size can be determined
3. mallocs that cannot be determined to be of type 1 or 2 and cannot be optimized

getMallocArraySize() returns NULL for category 3, and all users of this function must avoid their 
malloc optimization if this function returns NULL.

Eventually, currently unexpected codegen for computing the malloc's size argument will be supported in
isArrayMalloc() and getMallocArraySize(), extending malloc optimizations to those examples.

llvm-svn: 84199
2009-10-15 20:14:52 +00:00
Dan Gohman e525d9ddc0 Remove an unnnecessary LLVMContext argument in
ConstantFoldLoadThroughGEPConstantExpr.

llvm-svn: 83311
2009-10-05 16:36:26 +00:00
Nick Lewycky 1303c0ab86 Remove the default value for ConstantStruct::get's isPacked parameter and
update the code which was broken by this.

llvm-svn: 82327
2009-09-19 20:30:26 +00:00
Victor Hernandez 5d034499ad Enhance transform passes so that they apply the same tranforms to malloc calls as to MallocInst.
Reviewed by Dan Gohman.

llvm-svn: 82300
2009-09-18 22:35:49 +00:00
Dan Gohman 7190d48075 Factor out the code for checking that all indices in a getelementptr are
within the notional bounds of the static type of the getelementptr (which
is not the same as "inbounds") from GlobalOpt into a utility routine,
and use it in ConstantFold.cpp to check whether there are any mis-behaved
indices.

llvm-svn: 81478
2009-09-10 23:37:55 +00:00
Dan Gohman 161429fe7e Don't commit stores with addresses that have indices that are not
compile-time constant integers or that are out of bounds for their
corresponding static array types. These can cause aliasing that
GlobalOpt assumes won't happen.

llvm-svn: 81165
2009-09-07 22:44:55 +00:00
Dan Gohman 82e747580f Don't commit addresses of aggregate values. This avoids problems with
an aggregate store overlapping a different aggregate store, despite
the stores having distinct addresses.

llvm-svn: 81164
2009-09-07 22:42:05 +00:00
Dan Gohman beee35a277 Fix GlobalOpt to avoid committing a store if the address getelementptr
is missing the inbounds flag. This is slightly conservative, but it
avoids problems with two constants pointing to the same address but
getting distinct entries in the Memory DenseMap.

llvm-svn: 81163
2009-09-07 22:40:13 +00:00
Dan Gohman 19244eaa4a Preserve the InBounds flag when evaluating a getelementptr instruction
into a getelementptr ConstantExpr.

llvm-svn: 81162
2009-09-07 22:34:43 +00:00
Dan Gohman f7f3fb1133 Simplify this code by using hasDefinitiveInitializer().
llvm-svn: 81161
2009-09-07 22:31:26 +00:00
Chris Lattner b25de3ff60 eliminate the "Value" printing methods that print to a std::ostream.
This required converting a bunch of stuff off DOUT and other cleanups.

llvm-svn: 79819
2009-08-23 04:37:46 +00:00
Dan Gohman 5d5bc6d000 Use hasDefinitiveInitializer() instead of testing the same thing
by hand, and fix a few places that were using hasInitializer() that
appear to depend on the initializer value.

llvm-svn: 79441
2009-08-19 18:20:44 +00:00
Dan Gohman 82ac81b1cc Fix a bug that caused globalopt to miscompile tramp3d: don't miss
unruly indices for arrays that are members of structs.

llvm-svn: 79337
2009-08-18 14:58:19 +00:00
Duncan Sands c4ce58d8fe Don't access the first element of a potentially empty
vector (&Formals[0]).  With this change llvm-gcc builds
with expensive checking enabled for C, C++ and Fortran.
While there, change a std::vector into a SmallVector.
This is partly gratuitous, but mostly because not all
STL vector implementations define the data method (and
it should be faster).

llvm-svn: 79237
2009-08-17 14:33:27 +00:00
Dan Gohman dbeb33936f Make TargetData optional in GlobalOpt and ArgumentPromotion.
llvm-svn: 78967
2009-08-14 00:11:03 +00:00
Owen Anderson 55f1c09e31 Push LLVMContexts through the IntegerType APIs.
llvm-svn: 78948
2009-08-13 21:58:54 +00:00
Dan Gohman 5476cfdb15 Remove a bunch more now-unnecessary Context arguments.
llvm-svn: 78809
2009-08-12 16:23:25 +00:00
Owen Anderson 03cb69fbd1 Privatize the StructType table, which unfortunately involves routing contexts through a number of APIs.
llvm-svn: 78258
2009-08-05 23:16:16 +00:00
Owen Anderson 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
Owen Anderson 23a204d91b Move getTrue() and getFalse() to 2.5-like APIs.
llvm-svn: 77685
2009-07-31 17:39:07 +00:00
Owen Anderson b292b8ce70 Move more code back to 2.5 APIs.
llvm-svn: 77635
2009-07-30 23:03:37 +00:00
Daniel Dunbar 132f78395a Twines: Don't allow implicit conversion from integers, this is too tricky.
llvm-svn: 77605
2009-07-30 17:37:43 +00:00
Daniel Dunbar 6afdc5e694 Switch obvious clients to Twine instead of utostr (when they were already using
a Twine, e.g., for names).
 - I am a little ambivalent about this; we don't want the string conversion of
   utostr, but using overload '+' mixed with string and integer arguments is
   sketchy. On the other hand, this particular usage is something of an idiom.

llvm-svn: 77579
2009-07-30 04:20:37 +00:00
Owen Anderson 4056ca9568 Move types back to the 2.5 API.
llvm-svn: 77516
2009-07-29 22:17:13 +00:00
Owen Anderson 487375e9a2 Move ConstantExpr to 2.5 API.
llvm-svn: 77494
2009-07-29 18:55:55 +00:00
Owen Anderson c2c7932c64 Change ConstantArray to 2.5 API.
llvm-svn: 77347
2009-07-28 18:32:17 +00:00
Owen Anderson 45308b578b Move ConstantStruct back to 2.5 API.
llvm-svn: 77266
2009-07-27 22:29:26 +00:00
Daniel Dunbar 0dd5e1ed39 More migration to raw_ostream, the water has dried up around the iostream hole.
- Some clients which used DOUT have moved to DEBUG. We are deprecating the
   "magic" DOUT behavior which avoided calling printing functions when the
   statement was disabled. In addition to being unnecessary magic, it had the
   downside of leaving code in -Asserts builds, and of hiding potentially
   unnecessary computations.

llvm-svn: 77019
2009-07-25 00:23:56 +00:00
Owen Anderson 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
Owen Anderson 47db941fd3 Get rid of the Pass+Context magic.
llvm-svn: 76702
2009-07-22 00:24:57 +00:00
Owen Anderson c37bc69e91 Rename getConstantInt{True|False} to get{True|False} at Chris' behest.
llvm-svn: 76598
2009-07-21 18:03:38 +00:00
Owen Anderson 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
Owen Anderson 4fdeba9706 Revert yesterday's change by removing the LLVMContext parameter to AllocaInst and MallocInst.
llvm-svn: 75863
2009-07-15 23:53:25 +00:00
Owen Anderson b6b2530000 Move EVER MORE stuff over to LLVMContext.
llvm-svn: 75703
2009-07-14 23:09:55 +00:00
Torok Edwin 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
Owen Anderson 542619e6d5 Move more functionality over to LLVMContext.
llvm-svn: 75497
2009-07-13 20:58:05 +00:00
Torok Edwin 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
Owen Anderson 1e5f00e7a7 This started as a small change, I swear. Unfortunately, lots of things call the [I|F]CmpInst constructors. Who knew!?
llvm-svn: 75200
2009-07-09 23:48:35 +00:00
Owen Anderson b17f32945f Switch GlobalVariable ctors to a sane API, where *either* a context or a module is required.
llvm-svn: 75025
2009-07-08 19:03:57 +00:00
Owen Anderson 5948fdf68b Push LLVMContext through GlobalVariables and IRBuilder.
llvm-svn: 74985
2009-07-08 01:26:06 +00:00
Owen Anderson 38264b1554 "LLVMContext* " --> "LLVMContext *"
llvm-svn: 74878
2009-07-06 23:00:19 +00:00
Owen Anderson 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
Owen Anderson 605a8c743f More LLVMContext-ification.
llvm-svn: 74811
2009-07-06 01:34:54 +00:00
Chris Lattner 96122debc1 improve the APIs for creating struct and function types with no arguments/elements
to not have to create a temporary vector (in the API at least).  Patch by Jay Foad!

llvm-svn: 74584
2009-07-01 04:13:31 +00:00
Sanjiv Gupta 2f2b0a1985 >> What if my global variable was into a different address space than stack?
>>     
>
> It doesn't matter in terms of semantics: because AnalyzeGlobal
> returned false, we're guaranteed the address of the global is never
> taken.  I wouldn't be surprised if we end up generating invalid IR in
> some cases, though, because of the semantics of replaceAllUsesWith.
> Do you have a testcase that breaks?
>
>   
The problem is replaceAllUsesWith asserts for type mismatch here. Try attached .bc with llvm-ld.

assert(New->getType() == getType() &&
        "replaceAllUses of value with new value of different type!");

Since stack is always on address space zero, I don't think that type of GV in a different address space is ever going to match.
The other way is to allow replaceAllUsesWith to ignore address spaces while comparing types. (do we have  a way to do that ?).
But then such an optimization may fail the entire idea of user wanting to place a variable into different memory space. The original idea of user might be to save on the stack space (data memory) and hence he asked the variable to be placed into different memory space (program memory). So the best bet here is to deny this optimization by checking

GV->getType()->getAddressSpace() == 0. 

llvm-svn: 73605
2009-06-17 06:47:15 +00:00
Jay Foad 557169d923 Implement and use new method Function::hasAddressTaken().
llvm-svn: 73164
2009-06-10 08:41:11 +00:00
Jay Foad edea37d801 Remove an unused function SafeToDestroyConstant(). Rename an almost
identical function ConstantIsDead() to SafeToDestroyConstant(), to
emphasise the connection with Constant::destroyConstant().

llvm-svn: 73149
2009-06-09 21:37:11 +00:00