Teach simplifycfg that setcc is cheap and non-trapping, so that it can
convert this:
%tmp.1 = seteq int %i, 0 ; <bool> [#uses=1]
br bool %tmp.1, label %shortcirc_done, label %shortcirc_next
shortcirc_next: ; preds = %entry
%tmp.4 = seteq int %j, 0 ; <bool> [#uses=1]
br label %shortcirc_done
shortcirc_done: ; preds = %shortcirc_next, %entry
%shortcirc_val = phi bool [ %tmp.4, %shortcirc_next ], [ true, %entry ] ; <bool> [#uses=1]
to this:
%tmp.1 = seteq int %i, 0 ; <bool> [#uses=1]
%tmp.4 = seteq int %j, 0 ; <bool> [#uses=1]
%shortcirc_val = select bool %tmp.1, bool true, bool %tmp.4 ; <bool> [#uses=1]
... which is later simplified by instcombine into an or.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21388 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed