Andrew Haley writes:
>
> The easiest way to do that is simply to disable the patterns that
> generate the floating-point operations. I think the pattern is this
> one:
>
> (define_insn "*movdi_internal64"
> [(set (match_operand:DI 0 "nonimmediate_operand" "=r,r,m,r,r,r,r,*f,*f,m,r,*h,*h")
> (match_operand:DI 1 "input_operand" "r,m,r,I,L,nF,R,f,m,f,*h,r,0"))]
> "TARGET_POWERPC64
> && (gpc_reg_operand (operands[0], DImode)
> || gpc_reg_operand (operands[1], DImode))"
> "@
> mr %0,%1
> ld%U1%X1 %0,%1
> std%U0%X0 %1,%0
> li %0,%1
> lis %0,%v1
> #
> {cal|la} %0,%a1
> fmr %0,%1
> lfd%U1%X1 %0,%1
> stfd%U0%X0 %1,%0
> mf%1 %0
> mt%0 %1
> {cror 0,0,0|nop}"
> [(set_attr "type" "*,load,store,*,*,*,*,fp,fpload,fpstore,mfjmpr,mtjmpr,*")
> (set_attr "length" "4,4,4,4,4,20,4,4,4,4,4,4,4")])
>
> You'd want to remove the operations with "f" in their constraint
> pattern: that is, no. 8 and 9.
8, 9, and 10.
> An alternative idea would be to alter
> the cost of the opration so that the compiler never chooses to put a
> float in an int register.
>
> Andrew.
