![Linus Torvalds](/assets/img/avatar_default.png)
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
218 lines
3.5 KiB
ArmAsm
218 lines
3.5 KiB
ArmAsm
#include <asm/ppc_asm.h>
|
|
#include <asm/processor.h>
|
|
|
|
/*
|
|
* The routines below are in assembler so we can closely control the
|
|
* usage of floating-point registers. These routines must be called
|
|
* with preempt disabled.
|
|
*/
|
|
.data
|
|
fpzero:
|
|
.long 0
|
|
fpone:
|
|
.long 0x3f800000 /* 1.0 in single-precision FP */
|
|
fphalf:
|
|
.long 0x3f000000 /* 0.5 in single-precision FP */
|
|
|
|
.text
|
|
/*
|
|
* Internal routine to enable floating point and set FPSCR to 0.
|
|
* Don't call it from C; it doesn't use the normal calling convention.
|
|
*/
|
|
fpenable:
|
|
mfmsr r10
|
|
ori r11,r10,MSR_FP
|
|
mtmsr r11
|
|
isync
|
|
stfd fr0,24(r1)
|
|
stfd fr1,16(r1)
|
|
stfd fr31,8(r1)
|
|
lis r11,fpzero@ha
|
|
mffs fr31
|
|
lfs fr1,fpzero@l(r11)
|
|
mtfsf 0xff,fr1
|
|
blr
|
|
|
|
fpdisable:
|
|
mtfsf 0xff,fr31
|
|
lfd fr31,8(r1)
|
|
lfd fr1,16(r1)
|
|
lfd fr0,24(r1)
|
|
mtmsr r10
|
|
isync
|
|
blr
|
|
|
|
/*
|
|
* Vector add, floating point.
|
|
*/
|
|
.globl vaddfp
|
|
vaddfp:
|
|
stwu r1,-32(r1)
|
|
mflr r0
|
|
stw r0,36(r1)
|
|
bl fpenable
|
|
li r0,4
|
|
mtctr r0
|
|
li r6,0
|
|
1: lfsx fr0,r4,r6
|
|
lfsx fr1,r5,r6
|
|
fadds fr0,fr0,fr1
|
|
stfsx fr0,r3,r6
|
|
addi r6,r6,4
|
|
bdnz 1b
|
|
bl fpdisable
|
|
lwz r0,36(r1)
|
|
mtlr r0
|
|
addi r1,r1,32
|
|
blr
|
|
|
|
/*
|
|
* Vector subtract, floating point.
|
|
*/
|
|
.globl vsubfp
|
|
vsubfp:
|
|
stwu r1,-32(r1)
|
|
mflr r0
|
|
stw r0,36(r1)
|
|
bl fpenable
|
|
li r0,4
|
|
mtctr r0
|
|
li r6,0
|
|
1: lfsx fr0,r4,r6
|
|
lfsx fr1,r5,r6
|
|
fsubs fr0,fr0,fr1
|
|
stfsx fr0,r3,r6
|
|
addi r6,r6,4
|
|
bdnz 1b
|
|
bl fpdisable
|
|
lwz r0,36(r1)
|
|
mtlr r0
|
|
addi r1,r1,32
|
|
blr
|
|
|
|
/*
|
|
* Vector multiply and add, floating point.
|
|
*/
|
|
.globl vmaddfp
|
|
vmaddfp:
|
|
stwu r1,-48(r1)
|
|
mflr r0
|
|
stw r0,52(r1)
|
|
bl fpenable
|
|
stfd fr2,32(r1)
|
|
li r0,4
|
|
mtctr r0
|
|
li r7,0
|
|
1: lfsx fr0,r4,r7
|
|
lfsx fr1,r5,r7
|
|
lfsx fr2,r6,r7
|
|
fmadds fr0,fr0,fr2,fr1
|
|
stfsx fr0,r3,r7
|
|
addi r7,r7,4
|
|
bdnz 1b
|
|
lfd fr2,32(r1)
|
|
bl fpdisable
|
|
lwz r0,52(r1)
|
|
mtlr r0
|
|
addi r1,r1,48
|
|
blr
|
|
|
|
/*
|
|
* Vector negative multiply and subtract, floating point.
|
|
*/
|
|
.globl vnmsubfp
|
|
vnmsubfp:
|
|
stwu r1,-48(r1)
|
|
mflr r0
|
|
stw r0,52(r1)
|
|
bl fpenable
|
|
stfd fr2,32(r1)
|
|
li r0,4
|
|
mtctr r0
|
|
li r7,0
|
|
1: lfsx fr0,r4,r7
|
|
lfsx fr1,r5,r7
|
|
lfsx fr2,r6,r7
|
|
fnmsubs fr0,fr0,fr2,fr1
|
|
stfsx fr0,r3,r7
|
|
addi r7,r7,4
|
|
bdnz 1b
|
|
lfd fr2,32(r1)
|
|
bl fpdisable
|
|
lwz r0,52(r1)
|
|
mtlr r0
|
|
addi r1,r1,48
|
|
blr
|
|
|
|
/*
|
|
* Vector reciprocal estimate. We just compute 1.0/x.
|
|
* r3 -> destination, r4 -> source.
|
|
*/
|
|
.globl vrefp
|
|
vrefp:
|
|
stwu r1,-32(r1)
|
|
mflr r0
|
|
stw r0,36(r1)
|
|
bl fpenable
|
|
lis r9,fpone@ha
|
|
li r0,4
|
|
lfs fr1,fpone@l(r9)
|
|
mtctr r0
|
|
li r6,0
|
|
1: lfsx fr0,r4,r6
|
|
fdivs fr0,fr1,fr0
|
|
stfsx fr0,r3,r6
|
|
addi r6,r6,4
|
|
bdnz 1b
|
|
bl fpdisable
|
|
lwz r0,36(r1)
|
|
mtlr r0
|
|
addi r1,r1,32
|
|
blr
|
|
|
|
/*
|
|
* Vector reciprocal square-root estimate, floating point.
|
|
* We use the frsqrte instruction for the initial estimate followed
|
|
* by 2 iterations of Newton-Raphson to get sufficient accuracy.
|
|
* r3 -> destination, r4 -> source.
|
|
*/
|
|
.globl vrsqrtefp
|
|
vrsqrtefp:
|
|
stwu r1,-48(r1)
|
|
mflr r0
|
|
stw r0,52(r1)
|
|
bl fpenable
|
|
stfd fr2,32(r1)
|
|
stfd fr3,40(r1)
|
|
stfd fr4,48(r1)
|
|
stfd fr5,56(r1)
|
|
lis r9,fpone@ha
|
|
lis r8,fphalf@ha
|
|
li r0,4
|
|
lfs fr4,fpone@l(r9)
|
|
lfs fr5,fphalf@l(r8)
|
|
mtctr r0
|
|
li r6,0
|
|
1: lfsx fr0,r4,r6
|
|
frsqrte fr1,fr0 /* r = frsqrte(s) */
|
|
fmuls fr3,fr1,fr0 /* r * s */
|
|
fmuls fr2,fr1,fr5 /* r * 0.5 */
|
|
fnmsubs fr3,fr1,fr3,fr4 /* 1 - s * r * r */
|
|
fmadds fr1,fr2,fr3,fr1 /* r = r + 0.5 * r * (1 - s * r * r) */
|
|
fmuls fr3,fr1,fr0 /* r * s */
|
|
fmuls fr2,fr1,fr5 /* r * 0.5 */
|
|
fnmsubs fr3,fr1,fr3,fr4 /* 1 - s * r * r */
|
|
fmadds fr1,fr2,fr3,fr1 /* r = r + 0.5 * r * (1 - s * r * r) */
|
|
stfsx fr1,r3,r6
|
|
addi r6,r6,4
|
|
bdnz 1b
|
|
lfd fr5,56(r1)
|
|
lfd fr4,48(r1)
|
|
lfd fr3,40(r1)
|
|
lfd fr2,32(r1)
|
|
bl fpdisable
|
|
lwz r0,36(r1)
|
|
mtlr r0
|
|
addi r1,r1,32
|
|
blr
|