(X >s -1) ? C1 : C2 and (X <s 0) ? C2 : C1
into ((X >>s 31) & (C2 - C1)) + C1, avoiding the conditional.
This optimization could be extended to take non-const C1 and C2 but we better
stay conservative to avoid code size bloat for now.
for
int sel(int n) {
return n >= 0 ? 60 : 100;
}
we now generate
sarl $31, %edi
andl $40, %edi
leal 60(%rdi), %eax
instead of
testl %edi, %edi
movl $60, %ecx
movl $100, %eax
cmovnsl %ecx, %eax
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107866 91177308-0d34-0410-b5e6-96231b3b80d8
implement some optimizations for MIN(MIN()) and MAX(MAX()) and
MIN(MAX()) etc. This substantially improves the code in PR5822 but
doesn't kick in much elsewhere. 2 max's were optimized in
pairlocalalign and one in smg2000.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91814 91177308-0d34-0410-b5e6-96231b3b80d8
phi nodes. Make sure to phi translate from the right block.
This fixes a llvm-building-llvm failure on GVN-PRE.cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82970 91177308-0d34-0410-b5e6-96231b3b80d8
simple constants for the true/false value of the select. We now
do phi translation etc. This really fixes PR4895 :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82917 91177308-0d34-0410-b5e6-96231b3b80d8
that are phi nodes. Also tighten up FoldOpIntoPhi to treat constantexpr
operands to phis just like other variables, avoiding moving constantexpr
computations around.
Patch by Daniel Dunbar.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82913 91177308-0d34-0410-b5e6-96231b3b80d8
Make use of the END. facility on all files > 1K so that we aren't wasting CPU
cycles searching for RUN: lines that we'll never find.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36059 91177308-0d34-0410-b5e6-96231b3b80d8
