DAGCombiner does this, but divisions expanded here miss this
optimization. Since 67aa18f165,
divisions have been expanded here and missed out on this
optimization. Avoids test regressions in a future patch.
This allows hoisting of a common code, for instance if denominator
is loop invariant. Current change is expansion only, adding licm to
the target pass list going to be a separate patch. Given this patch
changes to codegen are minor as the expansion is similar to that on
DAG. DAG expansion still must remain for R600.
Differential Revision: https://reviews.llvm.org/D48586
llvm-svn: 335868
Allowed folding for "and/or" binops with non-constant operand if
arguments of select are 0/-1 values.
Normally this code with "and" opcode does not get to a DAG combiner
and simplified yet in the InstCombine. However AMDGPU produces it
during lowering and InstCombine has no chance to optimize it out.
In turn the same pattern with "or" opcode can reach DAG.
Differential Revision: https://reviews.llvm.org/D48301
llvm-svn: 335250
Previously this folding was done only if select is a first operand.
However, for non-commutative operations constant may go before
select.
Differential Revision: https://reviews.llvm.org/D48223
llvm-svn: 335167