it modifies a functions attributes.

llvm-svn: 55831

llvm-svn: 55785

llvm-svn: 55779

llvm-svn: 55766

llvm-svn: 55745

Initial version of a Partial Specialization IPO pass.  It triggers a couple hundred times on 176.gcc.  I don't know the performance impact yet, the heuristic is quite simple still.

llvm-svn: 55734

llvm-svn: 55720

llvm-svn: 55717

llvm-svn: 55716

llvm-svn: 55713

llvm-svn: 55712

llvm-svn: 55711

llvm-svn: 55708

llvm-svn: 55676

llvm-svn: 55673

llvm-svn: 54780

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

llvm-svn: 54707

postfixing it with a number.

llvm-svn: 54468

r53941 (but this was not noticed due to the lack of a basic test for
SRETPromotion). 

llvm-svn: 54467

llvm-svn: 54464

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

llvm-svn: 53716

again canonicalizes {i32} into i32 and {} into void.

llvm-svn: 53610

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

llvm-svn: 53607

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

and return values live for those functions. This doesn't change anything yet,
but prepares for the coming commits.

llvm-svn: 53601

llvm-svn: 53600

RetOrArg::getDescription() as const.

llvm-svn: 53599

llvm-svn: 53598

llvm-svn: 53592

method, to slightly simplify control flow.

llvm-svn: 53591

llvm-svn: 53474

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

llvm-svn: 52736

llvm-svn: 52723

llvm-svn: 52705