stepanov on sparc; sparc backend scheduling issues

[David Edelsohn]

	Sigh.  On PowerPC, the first loops look like:

._Z10accumulateIPddET0_T_S2_S1_:
LFB..18:
        cmpw 0,3,4
        beqlr- 0
L..218:
        mr 9,3
        addi 3,3,8
        lfd 0,0(9)
        cmpw 0,3,4
        fadd 1,1,0
        bne+ 0,L..218
        blr

but later loops look like:

._Z10accumulateI14double_pointerdET0_T_S2_S1_:
LFB..20:
        mr 0,3
        stw 3,24(1)
        cmpw 0,0,4
        beqlr- 0
L..236:
        lwz 9,24(1)
        addi 0,9,8
        lfd 0,0(9)
        cmpw 0,0,4
        stw 0,24(1)
        fadd 1,1,0
        bne+ 0,L..236
        blr

repeatedly moving the address in and out of a stack slot instead of
keeping the value in a register.  This is not good.

David