>>
>
> 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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73605 91177308-0d34-0410-b5e6-96231b3b80d8
identical function ConstantIsDead() to SafeToDestroyConstant(), to
emphasise the connection with Constant::destroyConstant().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73149 91177308-0d34-0410-b5e6-96231b3b80d8
to find a tiny mouse hole to squeeze through, it struck
me that globals without a name can be considered internal
since they can't be referenced from outside the current
module. This patch makes GlobalOpt give them internal
linkage. Also done for aliases even though they always
have names, since in my opinion anonymous aliases should
be allowed for consistency with global variables and
functions. So if that happens one day, this code is ready!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66267 91177308-0d34-0410-b5e6-96231b3b80d8
If non constant local GV named A is used by a constant local GV named B (e.g. llvm.dbg.variable) and B is not used by anyone else then eliminate A as well as B.
In other words, debug info should not interfere in removal of unused GV.
--This life, and those below, will be ignored--
M test/Transforms/GlobalOpt/2009-03-03-dbg.ll
M lib/Transforms/IPO/GlobalOpt.cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66167 91177308-0d34-0410-b5e6-96231b3b80d8
here. Since we only do the transform if there is
one use, strip off any such users in the hope of
making the transform fire more often.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64926 91177308-0d34-0410-b5e6-96231b3b80d8
alias can be morphed into the target. Implement this
transform, and fix a crash in the existing transform at
the same time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64583 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62869 91177308-0d34-0410-b5e6-96231b3b80d8
vector and extraneous loop over it, 2) not delete globals used by
phis/selects etc which could actually be useful. This fixes PR3321.
Many thanks to Duncan for narrowing this down.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62201 91177308-0d34-0410-b5e6-96231b3b80d8
nodes. This allows it to do fairly general phi insertion if a
load from a pointer global wants to be SRAd but the load is used
by (recursive) phi nodes. This fixes a pessimization on ppc
introduced by Load PRE.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61123 91177308-0d34-0410-b5e6-96231b3b80d8
s/ParamAttr/Attribute/g
s/PAList/AttrList/g
s/FnAttributeWithIndex/AttributeWithIndex/g
s/FnAttr/Attribute/g
This sets the stage
- to implement function notes as function attributes and
- to distinguish between function attributes and return value attributes.
This requires corresponding changes in llvm-gcc and clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56622 91177308-0d34-0410-b5e6-96231b3b80d8
several things that were neither in an anonymous namespace nor static
but not intended to be global.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51017 91177308-0d34-0410-b5e6-96231b3b80d8
