reload1.c (emit_reload_insns): If an output reload copies only to a secondary reload...

	* reload1.c (emit_reload_insns): If an output reload copies only
	to a secondary reload register, indicate that the secondary reload
	does the actual store.

From-SVN: r21034

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e359a9cb3d32e711d49158a8cf37a06cd6e98df3..a373deb99f3d920b1d8f32b0b59e0b31fa5dafaa 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+Thu Jul  9 18:12:49 1998  J"orn Rennecke <amylaar@cygnus.co.uk>
+
+       * reload1.c (emit_reload_insns): If an output reload copies only
+       to a secondary reload register, indicate that the secondary reload
+       does the actual store.
+
 Thu Jul  9 18:01:05 1998  J"orn Rennecke <amylaar@cygnus.co.uk>
 
        * reload.c (find_equiv_reg): If need_stable_sp is set,

diff --git a/gcc/reload1.c b/gcc/reload1.c
index b6c0d8d85090e2576372330eabd3707cd9229508..b115a94adbac730f03d34e63ceb909c6b8cf7bec 100644 (file)
--- a/gcc/reload1.c
+++ b/gcc/reload1.c
@@ -7085,7 +7085,35 @@ emit_reload_insns (insn)
                          SET_HARD_REG_BIT (reg_reloaded_died, src);
                      }
                    if (reload_spill_index[j] >= 0)
-                     new_spill_reg_store[reload_spill_index[j]] = p;
+                     {
+                       int s = reload_secondary_out_reload[j];
+                       rtx set = single_set (p);
+                       /* If this reload copies only to the secondary reload
+                          register, the secondary reload does the actual
+                          store.  */
+                       if (s >= 0 && set == NULL_RTX)
+                         ; /* We can't tell what function the secondary reload
+                              has and where the actual store to the pseudo is
+                              made; leave new_spill_reg_store alone.  */
+                       else if (s >= 0
+                           && SET_SRC (set) == reload_reg_rtx[j]
+                           && SET_DEST (set) == reload_reg_rtx[s])
+                         {
+                           /* Usually the next instruction will be the
+                              secondary reload insn;  if we can confirm
+                              that it is, setting new_spill_reg_store to
+                              that insn will allow an extra optimization.  */
+                           rtx s_reg = reload_reg_rtx[s];
+                           rtx next = NEXT_INSN (p);
+                           reload_out[s] = reload_out[j];
+                           set = single_set (next);
+                           if (set && SET_SRC (set) == s_reg
+                               && ! new_spill_reg_store[REGNO (s_reg)])
+                             new_spill_reg_store[REGNO (s_reg)] = next;
+                         }
+                       else
+                         new_spill_reg_store[reload_spill_index[j]] = p;
+                     }
                  }
              }