predecessors before returning. Otherwise, if multiple predecessor edges need
splitting, we only get one of them per iteration. This makes a small but
measurable compile time improvement with -enable-full-load-pre.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97521 91177308-0d34-0410-b5e6-96231b3b80d8
which branch on undef to branch on a boolean constant for the edge
exiting the loop. This helps ScalarEvolution compute trip counts for
loops.
Teach ScalarEvolution to recognize single-value PHIs, when safe, and
ForgetSymbolicName to forget such single-value PHI nodes as apprpriate
in ForgetSymbolicName.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97126 91177308-0d34-0410-b5e6-96231b3b80d8
argument is non-null, pass it along to PHITranslateSubExpr so that it can
prefer using existing values that dominate the PredBB, instead of just
blindly picking the first equivalent value that it finds on a uselist.
Also when the DominatorTree is specified, have PHITranslateValue filter
out any result that does not dominate the PredBB. This is basically just
refactoring the check that used to be in GetAvailablePHITranslatedSubExpr
and also in GVN.
Despite my initial expectations, this change does not affect the results
of GVN for any testcases that I could find, but it should help compile time.
Before this change, if PHITranslateSubExpr picked a value that does not
dominate, PHITranslateWithInsertion would then insert a new value, which GVN
would later determine to be redundant and would replace. By picking a good
value to begin with, we save GVN the extra work of inserting and then
replacing a new value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97010 91177308-0d34-0410-b5e6-96231b3b80d8
induction variable value and a loop-variant value, don't force the
insert position to be at the post-increment position, because it may
not be dominated by the loop-variant value. This fixes a
use-before-def problem noticed on PPC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96774 91177308-0d34-0410-b5e6-96231b3b80d8
strides in foreign loops. This helps locate reuse opportunities
with existing induction variables in foreign loops and reduces
the need for inserting new ones. This fixes rdar://7657764.
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a loop exit value, so that if a loop gets deleted, ScalarEvolution
isn't stick holding on to dangling SCEVAddRecExprs for that loop. This
fixes PR6339.
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and T->isPointerTy(). Convert most instances of the first form to the second form.
Requested by Chris.
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as it also peeks at which registers are being used by other uses. This
makes LSR less sensitive to use-list order.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96308 91177308-0d34-0410-b5e6-96231b3b80d8
with multiplication by constants distributed through, occasionally
those subexpressions can include both x and -x. For now, if this
condition is discovered within LSR, just prune such cases away,
as they won't be profitable. This fixes a "zero allocated in a
base register" assertion failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96177 91177308-0d34-0410-b5e6-96231b3b80d8
and add a doxygen comment.
Cache the phi entry to avoid doing tons of
PHINode::getBasicBlockIndex calls in the common case.
On my insane testcase from re2c, this speeds up CGP from
617.4s to 7.9s (78x).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96083 91177308-0d34-0410-b5e6-96231b3b80d8
