references. For example, this allows gvn to eliminate the load in
this example:
void foo(int n, int* p, int *q) {
p[0] = 0;
p[1] = 1;
if (n) {
*q = p[0];
}
}
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118714 91177308-0d34-0410-b5e6-96231b3b80d8
memory. This isn't a real improvement with present day AliasAnalysis
implementations; it's mainly for consistency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118624 91177308-0d34-0410-b5e6-96231b3b80d8
to optionally look for constant or local (alloca) memory.
Teach BasicAliasAnalysis::pointsToConstantMemory to look through Select
and Phi nodes, and to support looking for local memory.
Remove FunctionAttrs' PointsToLocalOrConstantMemory function, now that
AliasAnalysis knows all the tricks that it knew.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118412 91177308-0d34-0410-b5e6-96231b3b80d8
threshold given to createFunctionInliningPass().
Both opt -O3 and clang would silently ignore the -inline-threshold option.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118117 91177308-0d34-0410-b5e6-96231b3b80d8
consider it to be readonly. In fact, don't even consider it to be
readonly if it does a volatile load from an AllocaInst either (it
is debatable as to whether readonly would be correct or not in this
case; play safe for the moment). This fixes PR8279.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117783 91177308-0d34-0410-b5e6-96231b3b80d8
This code had previously used 2*N, where N is the mask length, to represent
undef. That is not safe because the shufflevector operands may have more
than N elements -- they don't have to match the result type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117721 91177308-0d34-0410-b5e6-96231b3b80d8
Allow splats even if they don't match either of the original shuffles,
possibly due to undef entries in the shuffles masks. Radar 8597790.
Also fix some 80-column violations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117719 91177308-0d34-0410-b5e6-96231b3b80d8
needs to be guaranteed never to be run on an unreachable block. However, earlier block simplifications may have
changed the CFG to make block that were reachable when we began our iteration unreachable by the time we try to
simplify them. (Note that this also means that our depth-first iterators were potentially being invalidated).
This should not have a large impact on code quality, since later runs of instcombine should pick up these simplifications.
Fixes PR8506.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117709 91177308-0d34-0410-b5e6-96231b3b80d8
it isn't unreachable and should not be zapped. The check for the entry block
was missing in one case: a block containing a unwind instruction. While there,
do some small cleanups: "M" is not a great name for a Function* (it would be
more appropriate for a Module*), change it to "Fn"; use Fn in more places.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117224 91177308-0d34-0410-b5e6-96231b3b80d8
must be called in the pass's constructor. This function uses static dependency declarations to recursively initialize
the pass's dependencies.
Clients that only create passes through the createFooPass() APIs will require no changes. Clients that want to use the
CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h
before parsing commandline arguments.
I have tested this with all standard configurations of clang and llvm-gcc on Darwin. It is possible that there are problems
with the static dependencies that will only be visible with non-standard options. If you encounter any crash in pass
registration/creation, please send the testcase to me directly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116820 91177308-0d34-0410-b5e6-96231b3b80d8
perform initialization without static constructors AND without explicit initialization
by the client. For the moment, passes are required to initialize both their
(potential) dependencies and any passes they preserve. I hope to be able to relax
the latter requirement in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116334 91177308-0d34-0410-b5e6-96231b3b80d8
formulae which become illegal as a result of the offset updating don't
escape.
This is for rdar://8529692. No testcase yet, because the given cases
hit use-list ordering differences.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116093 91177308-0d34-0410-b5e6-96231b3b80d8
This doesn't usually matter, because the other heuristics usually
succeed regardless, but it's good to keep the register use
bookkeeping consistent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116005 91177308-0d34-0410-b5e6-96231b3b80d8
initialization functions that initialize the set of passes implemented in
that library. Add C bindings for these functions as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115927 91177308-0d34-0410-b5e6-96231b3b80d8
a header declaring them all. This is also where we will declare per-library pass-set
initializer functions down the road.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115900 91177308-0d34-0410-b5e6-96231b3b80d8
Anyone interested in more general PRE would be better served by implementing it separately, to get real
anticipation calculation, etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115337 91177308-0d34-0410-b5e6-96231b3b80d8
The x86_mmx type is used for MMX intrinsics, parameters and
return values where these use MMX registers, and is also
supported in load, store, and bitcast.
Only the above operations generate MMX instructions, and optimizations
do not operate on or produce MMX intrinsics.
MMX-sized vectors <2 x i32> etc. are lowered to XMM or split into
smaller pieces. Optimizations may occur on these forms and the
result casted back to x86_mmx, provided the result feeds into a
previous existing x86_mmx operation.
The point of all this is prevent optimizations from introducing
MMX operations, which is unsafe due to the EMMS problem.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115243 91177308-0d34-0410-b5e6-96231b3b80d8
code size (making this transform code size neutral), and it allows us to hoist values out of loops, which is always
a good thing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115205 91177308-0d34-0410-b5e6-96231b3b80d8
Because of this, we cannot use the Simplify* APIs, as they can assert-fail on unreachable code. Since it's not easy to determine
if a given threading will cause a block to become unreachable, simply defer simplifying simplification to later InstCombine and/or
DCE passes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115082 91177308-0d34-0410-b5e6-96231b3b80d8
register pressure and thus excess spills, which we don't currently recover from well. This should
be re-evaluated in the future if our ability to generate good spills/splits improves.
Partial fix for <rdar://problem/7635585>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114919 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts revision 114633. It was breaking llvm-gcc-i386-linux-selfhost.
It seems there is a downstream bug that is exposed by
-cgp-critical-edge-splitting=0. When that bug is fixed, this patch can go back
in.
Note that the changes to tailcallfp2.ll are not reverted. They were good are
required.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114859 91177308-0d34-0410-b5e6-96231b3b80d8
Splitting critical edges at the merge point only addressed part of the issue; it is also possible for non-post-domination
to occur when the path from the load to the merge has branches in it. Unfortunately, full anticipation analysis is
time-consuming, so for now approximate it. This is strictly more conservative than real anticipation, so we will miss
some cases that real PRE would allow, but we also no longer insert loads into paths where they didn't exist before. :-)
This is a very slight net positive on SPEC for me (0.5% on average). Most of the benchmarks are largely unaffected, but
when it pays off it pays off decently: 181.mcf improves by 4.5% on my machine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114785 91177308-0d34-0410-b5e6-96231b3b80d8
"external" even when doing lazy bitcode loading. This was broken because
a function that is not materialized fails the !isDeclaration() test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114666 91177308-0d34-0410-b5e6-96231b3b80d8
truncates are free only in the case where the extended type is legal but the
load type is not. If both types are illegal, such as when they are too big,
the load may not be legalized into an extended load.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114568 91177308-0d34-0410-b5e6-96231b3b80d8
load when the type of the load is not legal, even if truncates are not free.
The load is going to be legalized to an extending load anyway.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114488 91177308-0d34-0410-b5e6-96231b3b80d8
walking the asm arguments once and stashing their Values. This is
wrong because the same memory location can be in the list twice, and
if the first one has a sunkaddr substituted, the stashed value for the
second one will be wrong (use-after-free). PR 8154.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114104 91177308-0d34-0410-b5e6-96231b3b80d8
deleted. Fix this by doing the copyValue's before we delete stuff!
The testcase only repros the problem on my system with valgrind.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113820 91177308-0d34-0410-b5e6-96231b3b80d8
