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References: <bug-42505-17572@http.gcc.gnu.org/bugzilla/>
Subject: [Bug middle-end/42505] [4.4 / 4.5 regression] loop canonicalization causes a lot of unnecessary temporary variables
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------- Comment #1 from ramana at gcc dot gnu dot org  2010-01-04 23:44 -------
For completeness the options are with -mthumb -Os -march=armv5te ?  


With trunk I see a size of 52 bytes and this code.

        .type   test, %function
test:
        push    {r4, r5, r6, r7, lr}
        sub     sp, sp, #12
        mov     r7, r0
        str     r1, [sp, #4]
        mov     r6, r2
        mov     r5, #0
        b       .L2
.L4:
        add     r4, r7, r5
        ldr     r0, [r4, #4]
        bl      func
        sub     r6, r6, #1
        cmp     r0, #0
        beq     .L5
        ldr     r1, [sp, #4]
        add     r3, r1, r5
        ldmia   r4!, {r1, r2}
        stmia   r3!, {r1, r2}
        add     r5, r5, #8
.L2:
        cmp     r6, #0
        bne     .L4
        mov     r0, #1
        b       .L3
.L5:
        mov     r0, #0
.L3:
        add     sp, sp, #12
        @ sp needed for prologue
        pop     {r4, r5, r6, r7, pc}
        .size   test, .-test


-- 

ramana at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
      Known to fail|                            |4.4.0 4.5.0
      Known to work|                            |4.2.1
   Last reconfirmed|0000-00-00 00:00:00         |2010-01-04 23:44:35
               date|                            |
            Summary|loop canonicalization causes|[4.4 / 4.5 regression] loop
                   |a lot of unnecessary        |canonicalization causes a
                   |temporary variables         |lot of unnecessary temporary
                   |                            |variables


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42505