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[Bug target/28881] New: Improve epilogue code in m68k

From: "kazu at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>
To: gcc-bugs at gcc dot gnu dot org
Date: 29 Aug 2006 06:44:08 -0000
Subject: [Bug target/28881] New: Improve epilogue code in m68k
Reply-to: gcc-bugzilla at gcc dot gnu dot org

m68k_output_function_epilogue uses leaf_function_p.
Consider using (stack_pointer_delta == 0) instead.
A quick experiment shows improvements like so:

-       move.l -8(%fp),%d2
-       move.l -4(%fp),%d3
+       move.l (%sp)+,%d2
+       move.l (%sp)+,%d3
        unlk %fp
        rts

Note that the move.l instruction without a displacement is shorter than the one
with a displacement.


-- 
           Summary: Improve epilogue code in m68k
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: kazu at gcc dot gnu dot org
GCC target triplet: m68k-none-elf


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28881

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