ack/mach/powerpc/libem/aar4.s

#
! $Source$
! $State$
! $Revision$

#include "powerpc.h"

.sect .text
	
! Index into a bounds-checked array.
!
! On entry:
!    r3 = ptr to descriptor
!    r4 = index
!    r5 = address of array
! Yields:
!    r3 = address of element
!    r0 = size of element (used by .lar4, .sar4)
! Preserves r10 for .lar4, .sar4

.define .aar4
.aar4:
	li32 r0, .trap_earray
	mtspr ctr, r0            ! load CTR with trap address

	lwz r0, 0(r3)
	subf. r4, r0, r4         ! adjust range
	bcctr IFTRUE, LT, 0      ! check lower bound
	
	lwz r0, 4(r3)
	cmpl cr0, 0, r4, r3
	bcctr IFFALSE, LT, 0     ! check upper bound
	
	lwz r0, 8(r3)
	mullw r4, r4, r0         ! scale index
	add r3, r4, r5           ! calculate element address
	
	bclr ALWAYS, 0, 0
Archival checkin (semi-working code). 2007-11-02 18:56:58 +00:00			`#`
			`! $Source$`
			`! $State$`
			`! $Revision$`

			`#include "powerpc.h"`

			`.sect .text`

			`! Index into a bounds-checked array.`
			`!`
			`! On entry:`
			`! r3 = ptr to descriptor`
			`! r4 = index`
			`! r5 = address of array`
Add the missing .lar4 and .sar4 for powerpc. Inspired by the sparc code (mach/sparc/libem/lar.s). My powerpc code might still have bugs, but it's enough for examples/hilo.mod to work. May need to 'make clean' or touch a build.lua file, so ackbuilder can notice the new lar4.s and sar4.s files and build them. 2016-09-18 03:55:55 +00:00			`! Yields:`
			`! r3 = address of element`
			`! r0 = size of element (used by .lar4, .sar4)`
			`! Preserves r10 for .lar4, .sar4`
Archival checkin (semi-working code). 2007-11-02 18:56:58 +00:00
			`.define .aar4`
			`.aar4:`
Rename our pseudo-opcode 'la' to 'li32'. GNU as has "la %r4,8(%r3)" as an alias for "addi %r4,%r3,8", meaning to load the address of the thing at 8(%r3). Our 'la', now 'li32', makes an addis/ori pair to load an immediate 32-bit value. For example, "li32 r4,23456789" loads a big number. 2016-09-18 21:03:23 +00:00			`li32 r0, .trap_earray`
Archival checkin (semi-working code). 2007-11-02 18:56:58 +00:00			`mtspr ctr, r0 ! load CTR with trap address`

			`lwz r0, 0(r3)`
			`subf. r4, r0, r4 ! adjust range`
			`bcctr IFTRUE, LT, 0 ! check lower bound`

			`lwz r0, 4(r3)`
			`cmpl cr0, 0, r4, r3`
			`bcctr IFFALSE, LT, 0 ! check upper bound`

			`lwz r0, 8(r3)`
			`mullw r4, r4, r0 ! scale index`
			`add r3, r4, r5 ! calculate element address`

			`bclr ALWAYS, 0, 0`