Vector register save and restore procedures

The vector save and restore functions are provided by the system (libc) as an aid to language compilers.

The vector save and restore functions listed below are provided by the system (libc) as an aid to language compilers.

On entry, r0 must contain the 16-byte aligned address just above the vector save area. r0 is left unchanged, but r12 is modified.

Item	Description
`_savev20:`	`addi`	`r12,`	`r0,`	`-192`
	`stvx`	`v20,`	`r12,`	`r0`	`# save v20`
`_savev21:`	`addi`	`r12,`	`r0,`	`-176`
	`stvx`	`v21,`	`r12,`	`r0`	`# save v21`
`_savev22:`	`addi`	`r12,`	`r0,`	`-160`
	`stvx`	`v22,`	`r12,`	`r0`	`# save v22`
`_savev23:`	`addi`	`r12,`	`r0,`	`-144`
	`stvx`	`v23,`	`r12,`	`r0`	`# save v23`
`_savev24:`	`addi`	`r12,`	`r0,`	`-128`
	`stvx`	`v24,`	`r12,`	`r0`	`# save v24`
`_savev25:`	`addi`	`r12,`	`r0,`	`-112`
	`stvx`	`v25,`	`r12,`	`r0`	`# save v25`
`_savev26:`	`addi`	`r12,`	`r0,`	`-96`
	`stvx`	`v26,`	`r12,`	`r0`	`# save v26`
`_savev27:`	`addi`	`r12,`	`r0,`	`-80`
	`stvx`	`v27,`	`r12,`	`r0`	`# save v27`
`_savev28:`	`addi`	`r12,`	`r0,`	`-64`
	`stvx`	`v28,`	`r12,`	`r0`	`# save v28`
`_savev29:`	`addi`	`r12,`	`r0,`	`-48`
	`stvx`	`v29,`	`r12,`	`r0`	`# save v29`
`_savev30:`	`addi`	`r12,`	`r0,`	`-32`
	`stvx`	`v30,`	`r12,`	`r0`	`# save v30`
`_savev31:`	`addi`	`r12,`	`r0,`	`-16`
	`stvx`	`v31,`	`r12,`	`r0`	`# save v31`
	`br`

`_restv20:`	`addi`	`r12,`	`r0,`	`-192`
	`lvx`	`v20,`	`r12,`	`r0`	`# restore v20`
`_restv21:`	`addi`	`r12,`	`r0,`	`-176`
	`lvx`	`v21,`	`r12,`	`r0`	`# restore v21`
`_restv22:`	`addi`	`r12,`	`r0,`	`-160`
	`lvx`	`v22,`	`r12,`	`r0`	`# restore v22`
`_restv23:`	`addi`	`r12,`	`r0,`	`-144`
	`lvx`	`v23,`	`r12,`	`r0`	`# restore v23`
`_restv24:`	`addi`	`r12,`	`r0,`	`-128`
	`lvx`	`v24,`	`r12,`	`r0`	`# restore v24`
`_restv25:`	`addi`	`r12,`	`r0,`	`-112`
	`lvx`	`v25,`	`r12,`	`r0`	`# restore v25`
`_restv26:`	`addi`	`r12,`	`r0,`	`-96`
	`lvx`	`v26,`	`r12,`	`r0`	`# restore v26`
`_restv27:`	`addi`	`r12,`	`r0,`	`-80`
	`lvx`	`v27,`	`r12,`	`r0`	`# restore v27`
`_restv28:`	`addi`	`r12,`	`r0,`	`-64`
	`lvx`	`v28,`	`r12,`	`r0`	`# restore v28`
`_restv29:`	`addi`	`r12,`	`r0,`	`-48`
	`lvx`	`v29,`	`r12,`	`r0`	`# restore v29`
`_restv30:`	`addi`	`r12,`	`r0,`	`-32`
	`lvx`	`v30,`	`r12,`	`r0`	`# restore v30`
`_restv31:`	`addi`	`r12,`	`r0,`	`-16`
	`lvx`	`v31,`	`r12,`	`r0`	`# restore v31`
	`br`