* reload1.c (eliminate_regs_in_insn): Recognize frame pointer

adjustments even if they are implemented by more than two insns.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@49221 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 75a1007..bec4e64 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2002-01-25  Ulrich Weigand  <uweigand@de.ibm.com>
+
+       * reload1.c (eliminate_regs_in_insn): Recognize frame pointer
+       adjustments even if they are implemented by more than two insns.
+
 Fri Jan 25 20:43:56 CET 2002  Jan Hubicka  <jh@suse.cz>
 
        * df.c (df_ref_create, df_ref_record_1, df_ref_record): Kill BB argument.

diff --git a/gcc/reload1.c b/gcc/reload1.c
index 521e482..5211b5f 100644 (file)
--- a/gcc/reload1.c
+++ b/gcc/reload1.c
@@ -2932,38 +2932,32 @@ eliminate_regs_in_insn (insn, replace)
            if (ep->from == FRAME_POINTER_REGNUM
                && ep->to == HARD_FRAME_POINTER_REGNUM)
              {
-               rtx src = SET_SRC (old_set);
-               int offset = 0, ok = 0;
-               rtx prev_insn, prev_set;
-
-               if (src == ep->to_rtx)
-                 offset = 0, ok = 1;
-               else if (GET_CODE (src) == PLUS
-                        && GET_CODE (XEXP (src, 0)) == CONST_INT
-                        && XEXP (src, 1) == ep->to_rtx)
-                 offset = INTVAL (XEXP (src, 0)), ok = 1;
-               else if (GET_CODE (src) == PLUS
-                        && GET_CODE (XEXP (src, 1)) == CONST_INT
-                        && XEXP (src, 0) == ep->to_rtx)
-                 offset = INTVAL (XEXP (src, 1)), ok = 1;
-               else if ((prev_insn = prev_nonnote_insn (insn)) != 0
-                        && (prev_set = single_set (prev_insn)) != 0
-                        && rtx_equal_p (SET_DEST (prev_set), src))
+               rtx base = SET_SRC (old_set);
+               rtx base_insn = insn;
+               int offset = 0;
+
+               while (base != ep->to_rtx)
                  {
-                   src = SET_SRC (prev_set);
-                   if (src == ep->to_rtx)
-                     offset = 0, ok = 1;
-                   else if (GET_CODE (src) == PLUS
-                            && GET_CODE (XEXP (src, 0)) == CONST_INT
-                            && XEXP (src, 1) == ep->to_rtx)
-                     offset = INTVAL (XEXP (src, 0)), ok = 1;
-                   else if (GET_CODE (src) == PLUS
-                            && GET_CODE (XEXP (src, 1)) == CONST_INT
-                            && XEXP (src, 0) == ep->to_rtx)
-                     offset = INTVAL (XEXP (src, 1)), ok = 1;
+                   rtx prev_insn, prev_set;
+
+                   if (GET_CODE (base) == PLUS
+                       && GET_CODE (XEXP (base, 1)) == CONST_INT)
+                     {
+                       offset += INTVAL (XEXP (base, 1));
+                       base = XEXP (base, 0);
+                     }
+                   else if ((prev_insn = prev_nonnote_insn (base_insn)) != 0
+                            && (prev_set = single_set (prev_insn)) != 0
+                            && rtx_equal_p (SET_DEST (prev_set), base))
+                     {
+                       base = SET_SRC (prev_set);
+                       base_insn = prev_insn;
+                     }
+                   else
+                     break;
                  }
 
-               if (ok)
+               if (base == ep->to_rtx)
                  {
                    rtx src
                      = plus_constant (ep->to_rtx, offset - ep->offset);