linkage: the value may be replaced with something
different at link time. (Frontends that want to
allow values to be loaded out of weak constants can
give their constants weak_odr linkage).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67407 91177308-0d34-0410-b5e6-96231b3b80d8
allocations. Apparently the assumption is there is an
instruction (terminator?) following the allocation so I
am allowing the same assumption.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66716 91177308-0d34-0410-b5e6-96231b3b80d8
use, check also for the case where it has two uses,
the other being a llvm.dbg.declare. This is needed so
debug info doesn't affect codegen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65970 91177308-0d34-0410-b5e6-96231b3b80d8
info with it.
Don't count debug info insns against the scan maximum
in FindAvailableLoadedValue (lest they affect codegen).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65910 91177308-0d34-0410-b5e6-96231b3b80d8
ashr instcombine to help expose this code. And apply the fix to
SelectionDAG's copy of this code too.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65364 91177308-0d34-0410-b5e6-96231b3b80d8
memcpy to match the alignment of the destination. It isn't necessary
for making loads and stores handled like the SSE loadu/storeu
intrinsics, and it was causing a performance regression in
MultiSource/Applications/JM/lencod.
The problem appears to have been a memcpy that copies from some
highly aligned array into an alloca; the alloca was then being
assigned a large alignment, which required codegen to perform
dynamic stack-pointer re-alignment, which forced the enclosing
function to have a frame pointer, which led to increased spilling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65289 91177308-0d34-0410-b5e6-96231b3b80d8
as legality. Make load sinking and gep sinking more careful: we only
do it when it won't pessimize loads from the stack. This has the added
benefit of not producing code that is unanalyzable to SROA.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65209 91177308-0d34-0410-b5e6-96231b3b80d8
eliminate all the extensions and all but the one required truncate
from the testcase, but the or/and/shift stuff still isn't zapped.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64809 91177308-0d34-0410-b5e6-96231b3b80d8
Enhance instcombine to use the preferred field of
GetOrEnforceKnownAlignment in more cases, so that regular IR operations are
optimized in the same way that the intrinsics currently are.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64623 91177308-0d34-0410-b5e6-96231b3b80d8
turn icmp eq a+x, b+x into icmp eq a, b if a+x or b+x has other uses. This
may have been increasing register pressure leading to the bzip2 slowdown.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63487 91177308-0d34-0410-b5e6-96231b3b80d8
improvements to the EvaluateInDifferentType code. This code works
by just inserted a bunch of new code and then seeing if it is
useful. Instcombine is not allowed to do this: it can only insert
new code if it is useful, and only when it is converging to a more
canonical fixed point. Now that we iterate when DCE makes progress,
this causes an infinite loop when the code ends up not being used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63483 91177308-0d34-0410-b5e6-96231b3b80d8
simplifydemandedbits to simplify instructions with *multiple
uses* in contexts where it can get away with it. This allows
it to simplify the code in multi-use-or.ll into a single 'add
double'.
This change is particularly interesting because it will cover
up for some common codegen bugs with large integers created due
to the recent SROA patch. When working on fixing those bugs,
this should be disabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63481 91177308-0d34-0410-b5e6-96231b3b80d8
Now, if it detects that "V" is the same as some other value,
SimplifyDemandedBits returns the new value instead of RAUW'ing it immediately.
This has two benefits:
1) simpler code in the recursive SimplifyDemandedBits routine.
2) it allows future fun stuff in instcombine where an operation has multiple
uses and can be simplified in one context, but not all.
#2 isn't implemented yet, this patch should have no functionality change.
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not doing so prevents it from properly iterating and prevents it
from deleting the entire body of dce-iterate.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63476 91177308-0d34-0410-b5e6-96231b3b80d8
Thus we need to check whether the struct is empty before trying to index into
it. This fixes PR3381.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62918 91177308-0d34-0410-b5e6-96231b3b80d8
handling the case in Transforms/InstCombine/cast-store-gep.ll, which
is a heavily reduced testcase from Clang on x86-64.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62904 91177308-0d34-0410-b5e6-96231b3b80d8
Besides APFloat, this involved removing code
from two places that thought they knew the
result of frem(0., x) but were wrong.
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