you should omit it from the machine description. You describe to the
compiler exactly which value is stored by defining the macro
@code{STORE_FLAG_VALUE} (@pxref{Misc}). If a description cannot be
-found that can be used for all the @samp{s@var{cond}} patterns, you
-should omit those operations from the machine description.
-
-These operations may fail, but should do so only in relatively
-uncommon cases; if they would fail for common cases involving
-integer comparisons, it is best to omit these patterns.
-
-If these operations are omitted, the compiler will usually generate code
-that copies the constant one to the target and branches around an
-assignment of zero to the target. If this code is more efficient than
-the potential instructions used for the @samp{cstore@var{mode}4} pattern
-followed by those required to convert the result into a 1 or a zero in
-@code{SImode}, you should omit the @samp{cstore@var{mode}4} operations from
-the machine description.
+found that can be used for all the possible comparison operators, you
+should pick one and use a @code{define_expand} to map all results
+onto the one you chose.
+
+These operations may @code{FAIL}, but should do so only in relatively
+uncommon cases; if they would @code{FAIL} for common cases involving
+integer comparisons, it is best to restrict the predicates to not
+allow these operands. Likewise if a given comparison operator will
+always fail, independent of the operands (for floating-point modes, the
+@code{ordered_comparison_operator} predicate is often useful in this case).
+
+If this pattern is omitted, the compiler will generate a conditional
+branch---for example, it may copy a constant one to the target and branching
+around an assignment of zero to the target---or a libcall. If the predicate
+for operand 1 only rejects some operators, it will also try reordering the
+operands and/or inverting the result value (e.g.@: by an exclusive OR).
+These possibilities could be cheaper or equivalent to the instructions
+used for the @samp{cstore@var{mode}4} pattern followed by those required
+to convert a positive result from @code{STORE_FLAG_VALUE} to 1; in this
+case, you can and should make operand 1's predicate reject some operators
+in the @samp{cstore@var{mode}4} pattern, or remove the pattern altogether
+from the machine description.
@cindex @code{cbranch@var{mode}4} instruction pattern
@item @samp{cbranch@var{mode}4}
@defmac STORE_FLAG_VALUE
A C expression describing the value returned by a comparison operator
with an integral mode and stored by a store-flag instruction
-(@samp{s@var{cond}}) when the condition is true. This description must
-apply to @emph{all} the @samp{s@var{cond}} patterns and all the
+(@samp{cstore@var{mode}4}) when the condition is true. This description must
+apply to @emph{all} the @samp{cstore@var{mode}4} patterns and all the
comparison operators whose results have a @code{MODE_INT} mode.
A value of 1 or @minus{}1 means that the instruction implementing the
which bits of the result are guaranteed to be 1 when the comparison is
true. This value is interpreted in the mode of the comparison
operation, which is given by the mode of the first operand in the
-@samp{s@var{cond}} pattern. Either the low bit or the sign bit of
+@samp{cstore@var{mode}4} pattern. Either the low bit or the sign bit of
@code{STORE_FLAG_VALUE} be on. Presently, only those bits are used by
the compiler.
Some machines can also perform @code{and} or @code{plus} operations on
condition code values with less instructions than the corresponding
-@samp{s@var{cond}} insn followed by @code{and} or @code{plus}. On those
+@samp{cstore@var{mode}4} insn followed by @code{and} or @code{plus}. On those
machines, define the appropriate patterns. Use the names @code{incscc}
and @code{decscc}, respectively, for the patterns which perform
@code{plus} or @code{minus} operations on condition code values. See
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