when combining add and sub instructions. Patch by Pranav Bhandarkar!

llvm-svn: 137570

  - use SmallVectorImpl& for the function argument.
  - ignore the operands on the GEP, even if they aren't constant! Much as we
    pretend the malloc succeeds, we pretend that malloc + whatever-you-GEP'd-by
    is not null. It's magic!

llvm-svn: 136757

Don't replace a gep/bitcast with 'undef' because that will form a "free(undef)"
which in turn means "unreachable". What we wanted was a no-op. Instead, analyze
the whole tree and look for all the instructions we need to delete first, then
delete them second, not relying on the use_list to stay consistent.

llvm-svn: 136752

malloc call.

llvm-svn: 136732

llvm-svn: 136585

llvm-svn: 135904

ArrayRef.

llvm-svn: 135761

llvm-svn: 135482

Migrate LLVM and Clang to use the new makeArrayRef(...) functions where previously explicit non-default constructors were used.
Mostly mechanical with some manual reformatting.

llvm-svn: 135390

llvm-svn: 135375

llvm-svn: 135040

more than one use.

Fixes PR10322.

llvm-svn: 134883

Final step of instcombine debuginfo; switch a couple more places over to InsertNewInstWith, and use setDebugLoc for the cases which can't be easily handled by the automated mechanisms.

llvm-svn: 132167

Make instcombine O(N) instead of O(N^2) in code where the same simplifiable constant is used many times.
Part of rdar://9471075.

llvm-svn: 131979

llvm-svn: 131604

Start trying to make InstCombine preserve more debug info.  The idea here is to set the debug location on the IRBuilder, which will be then right location in most cases.  This should magically give many transformations debug locations, and fixing places which are missing a debug location will usually just means changing the code creating it to use the IRBuilder.

As an example, the change to InstCombineCalls catches a common case where a call to a bitcast of a function is rewritten.

Chris, does this approach look reasonable?

llvm-svn: 131516

llvm-svn: 131512

effective in avoiding recomputation of LCSSA form; the widespread
use of instsimplify (which looks through phi nodes) means it was
not preserving LCSSA form anyway; and instcombine is no longer
scheduled in the middle of the loop passes so this doesn't matter
anymore.

llvm-svn: 130301

space info. We crash with an assert in this case. This change checks that the
address space of the bitcasted pointer is the same as the gep ptr.

llvm-svn: 128884

PHINode::Create() giving the (known or expected) number of operands.

llvm-svn: 128537

llvm-svn: 128406

This is done by lowering dbg.declare intrinsic into dbg.value intrinsic.
Radar 9143931.

llvm-svn: 127834

llvm-svn: 125547

reassociation. No testcase, because I wasn't able to create a testcase
which actually demonstrates a problem.

llvm-svn: 124713

llvm-svn: 123968

llvm-svn: 123965

a select. A vector select is pairwise on each element so we'd need a new
condition with the right number of elements to select on. Fixes PR8994.

llvm-svn: 123963

llvm-svn: 123569

multiple uses.  In some cases, all the uses are the same operation,
so instcombine can go ahead and promote the phi.  In the testcase
this pushes an add out of the loop.

llvm-svn: 123568

first line of the function because it isn't a good idea, even for compares.

llvm-svn: 123566

llvm-svn: 123565

llvm-svn: 123564

if both A op B and A op C simplify.  This fires fairly often but doesn't
make that much difference.  On gcc-as-one-file it removes two "and"s and
turns one branch into a select.

llvm-svn: 122399

instcombine is compared to instsimplify.

llvm-svn: 122397

llvm-svn: 122204

llvm-svn: 122183

Transform (extractvalue (load P), ...) to (load (gep P, 0, ...)) if the load has no other uses, shrinking the load.

llvm-svn: 120323

llvm-svn: 120051

Stylistic improvement suggested by Frits van Bommel.

llvm-svn: 120026

llvm-svn: 120025