subst_insn = i3;
- /* It is possible that the source of I2 or I1 may be performing an
- unneeded operation, such as a ZERO_EXTEND of something that is known
- to have the high part zero. Handle that case by letting subst look at
- the innermost one of them.
-
- Another way to do this would be to have a function that tries to
- simplify a single insn instead of merging two or more insns. We don't
- do this because of the potential of infinite loops and because
- of the potential extra memory required. However, doing it the way
- we are is a bit of a kludge and doesn't catch all cases.
-
- But only do this if -fexpensive-optimizations since it slows things down
- and doesn't usually win. */
-
- if (flag_expensive_optimizations)
- {
- /* Pass pc_rtx so no substitutions are done, just simplifications. */
- if (i1)
- {
- subst_low_cuid = INSN_CUID (i1);
- i1src = subst (i1src, pc_rtx, pc_rtx, 0, 0);
- }
- else
- {
- subst_low_cuid = INSN_CUID (i2);
- i2src = subst (i2src, pc_rtx, pc_rtx, 0, 0);
- }
- }
-
#ifndef HAVE_cc0
/* Many machines that don't use CC0 have insns that can both perform an
arithmetic operation and set the condition code. These operations will
else
#endif
{
+ /* It is possible that the source of I2 or I1 may be performing
+ an unneeded operation, such as a ZERO_EXTEND of something
+ that is known to have the high part zero. Handle that case
+ by letting subst look at the innermost one of them.
+
+ Another way to do this would be to have a function that tries
+ to simplify a single insn instead of merging two or more
+ insns. We don't do this because of the potential of infinite
+ loops and because of the potential extra memory required.
+ However, doing it the way we are is a bit of a kludge and
+ doesn't catch all cases.
+
+ But only do this if -fexpensive-optimizations since it slows
+ things down and doesn't usually win.
+
+ This is not done in the COMPARE case above because the
+ unmodified I2PAT is used in the PARALLEL and so a pattern
+ with a modified I2SRC would not match. */
+
+ if (flag_expensive_optimizations)
+ {
+ /* Pass pc_rtx so no substitutions are done, just
+ simplifications. */
+ if (i1)
+ {
+ subst_low_cuid = INSN_CUID (i1);
+ i1src = subst (i1src, pc_rtx, pc_rtx, 0, 0);
+ }
+ else
+ {
+ subst_low_cuid = INSN_CUID (i2);
+ i2src = subst (i2src, pc_rtx, pc_rtx, 0, 0);
+ }
+ }
+
n_occurrences = 0; /* `subst' counts here */
/* If I1 feeds into I2 (not into I3) and I1DEST is in I1SRC, we