when deciding whether to mark a function readnone/readonly.
Since the pass is currently run before SROA, this may be
quite helpful. Requested by Chris on IRC.
llvm-svn: 57050
- return attributes - inreg, zext and sext
- parameter attributes
- function attributes - nounwind, readonly, readnone, noreturn
Return attributes use 0 as the index.
Function attributes use ~0U as the index.
This patch requires corresponding changes in llvm-gcc and clang.
llvm-svn: 56704
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.
llvm-svn: 56622
can get the readnone/readonly attributes, and gives them it.
The plan is to remove markmodref (which did the same thing
by querying GlobalsModRef) and delete the analogous
functionality from GlobalsModRef.
llvm-svn: 56341
call (thus changing the call site) it didn't
inform the callgraph about this. But the
call site does matter - as shown by the testcase,
the callgraph become invalid after the inliner
ran (with an edge between two functions simply
missing), resulting in wrong deductions by
GlobalsModRef.
llvm-svn: 55872
because it does not maintain a correct list
of callsites. I discovered (see following
commit) that the inliner will create a wrong
callgraph if it is fed a callgraph with
correct edges but incorrect callsites. These
were created by Prune-EH, and while it wasn't
done via removeCallEdgeTo, it could have been
done via removeCallEdgeTo, which is an accident
waiting to happen. Use removeCallEdgeFor
instead.
llvm-svn: 55859
invalidating the iterator by deleting the current use. This fixes a segfault on
64 bit linux reported in PR2675.
Also remove an unneeded if.
llvm-svn: 54778
that says "unconditional loads from this argument are safe", we now keep track
of the safety per set of indices from which loads happen. This prevents
ArgPromotion from promoting loads that aren't really valid. As an added effect,
this will now disregard the the type of the indices passed to a GEP, so
"load GEP %A, i32 1" and "load GEP %A, i64 1" will result in a single argument,
not two.
This fixes PR2598, for which a testcase has been added as well.
llvm-svn: 54159
Remove the GetResultInst instruction. It is still accepted in LLVM assembly
and bitcode, where it is now auto-upgraded to ExtractValueInst. Also, remove
support for return instructions with multiple values. These are auto-upgraded
to use InsertValueInst instructions.
The IRBuilder still accepts multiple-value returns, and auto-upgrades them
to InsertValueInst instructions.
llvm-svn: 53941
return value as a whole in deadargelim is really not needed now that we simply
rebuild the old return value and actually prevents some canonicalization from
taking place.
This revert stops deadargelim from changing {i32} into i32 for now, but I'll
fix that next.
llvm-svn: 53609
return values that are still (partially) live. Instead of updating all uses of
a call instruction after removing some elements, it now just rebuilds the
original struct (With undef gaps where the unused values were) and leaves it to
instcombine to clean this up.
The added testcase still fails currently, but this is due to instcombine which
isn't good enough yet. I will fix that part next.
llvm-svn: 53608
only the liveness of partial return values (for functions returning a struct).
This is more explicit to prevent unwanted changes in the return value.
In particular, deadargelim now canonicalizes a function returning {i32} to
returning i32 and {} to void, if the struct returned is not used in its
entirety, but only the single element is used.
llvm-svn: 53606
Rewrite the DeadArgumentElimination pass, to use a more explicit tracking of
dependencies between return values and/or arguments. Also make the handling of
arguments and return values the same.
The pass now looks properly inside returned structs, but only at the first
level (ie, not inside nested structs).
This version fixed a few more bugs and was cleaned up a bit. It now passes all
of LLVM's testing, and should still pass SPEC2006. There is still a minor bug
with regard to returning nested structs. Since there is currently nothing that
emits such IR, I will fix that in a seperate commit (partly because it requires
a non-trivial fix).
llvm-svn: 53400
DeadArgumentElimination and assert that the function type does not change if
nothing was changed. This should catch subtle changes in function type that are
not intended.
llvm-svn: 52536
This is a fixed version that no longer uses multimap::equal_range, which
resulted in a pointer invalidation problem.
Also, DAE::InspectedFunctions was not really necessary, so it got removed.
Lastly, this version no longer applies the extra arg hack on functions who did
not have any arguments to start with.
llvm-svn: 52532
dependencies between return values and/or arguments. Also make the handling of
arguments and return values the same.
The pass now looks properly inside returned structs, but only at the first
level (ie, not inside nested structs).
Also add a testcase for testing various variations of (multiple) dead rerturn
values.
llvm-svn: 52459
speaking these are not constant values. However, when a function always returns
one of its arguments, then from the point of view of each caller the return
value is constant (or at least a known value) and can be replaced.
llvm-svn: 52397
individually.
Also learn IPConstProp how returning first class aggregates work, in addition
to old style multiple return instructions.
Modify the return-constants testscase to confirm this behaviour.
llvm-svn: 52396
the section or the visibility from one global
value to another: copyAttributesFrom. This is
particularly useful for duplicating functions:
previously this was done by explicitly copying
each attribute in turn at each place where a
new function was created out of an old one, with
the result that obscure attributes were regularly
forgotten (like the collector or the section).
Hopefully now everything is uniform and nothing
is forgotten.
llvm-svn: 51567
replaced at linktime with a body that throws, even
if the body in this file does not. Make PruneEH
be more conservative in this case.
g++.dg/eh/weak1.C
llvm-svn: 51207
a FunctionPass. This makes it simpler, fixes dozens of bugs, adds
a couple of minor features, and shrinks is considerably: from
2214 to 1437 lines.
llvm-svn: 50520
generalizes the previous code to handle the case when the string is not
an immediate to the strlen call (for example, crazy stuff like
strlen(c ? "foo" : "bart"+1) -> 3). This implements
gcc.c-torture/execute/builtins/strlen-2.c. I will generalize other
cases in simplifylibcalls to use the same routine later.
llvm-svn: 50408
2. Do not use # of basic blocks as part of the cost computation since it doesn't really figure into function size.
3. More aggressively inline function with vector code.
llvm-svn: 49061
Furthermore, double the limit when more than 10% of the callee instructions are vector instructions. Multimedia kernels tend to love inlining.
llvm-svn: 48725
1. There is now a "PAListPtr" class, which is a smart pointer around
the underlying uniqued parameter attribute list object, and manages
its refcount. It is now impossible to mess up the refcount.
2. PAListPtr is now the main interface to the underlying object, and
the underlying object is now completely opaque.
3. Implementation details like SmallVector and FoldingSet are now no
longer part of the interface.
4. You can create a PAListPtr with an arbitrary sequence of
ParamAttrsWithIndex's, no need to make a SmallVector of a specific
size (you can just use an array or scalar or vector if you wish).
5. All the client code that had to check for a null pointer before
dereferencing the pointer is simplified to just access the
PAListPtr directly.
6. The interfaces for adding attrs to a list and removing them is a
bit simpler.
Phase #2 will rename some stuff (e.g. PAListPtr) and do other less
invasive changes.
llvm-svn: 48289