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No need to restore r8-r14 on return from int if no context switch

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git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@1213 42af7a65-404d-4744-a932-0658087f49c3
This commit is contained in:
patacongo 2008-11-13 00:15:08 +00:00
parent 2015f47eba
commit 394753cd92
1 changed files with 16 additions and 5 deletions
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21
arch/sh/src/sh1/sh1_vector.S
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@ -345,7 +345,7 @@ _up_vector:
mov.l .Ldoirq, r0
jsr @r0
mov r15, r14
nop
/* Recover the user stack point */
@ -355,7 +355,7 @@ _up_vector:
mov.l .Ldoirq, r0
jsr @r0
mov r15, r14
nop
#endif
/* On return, R0 holds the address of the base of the XCPTCONTEXT
* structure to use for the return -- may not be the same as the
@ -368,17 +368,28 @@ _up_vector:
bf .Lcontextswitch
mov r0, r15
/* Restore registers from the stack. */
/* Restore registers from the stack. NOTE: We coudl improve interrupt
* performance by skipping the restore of r8-r14. These will not
* be modified by the called C code
*/
mov.l @r15+, r8 /* 0-8: r8-r14, pr, and gbr */
#if 1
/* Skip over static registers -- these will not be modified by the
* called C code (r8-r14)
*/
add #(7*4), r15 /* 0-6: Skip over r8-r14 */
#else
mov.l @r15+, r8 /* 0-6: r8-r14 */
mov.l @r15+, r9
mov.l @r15+, r10
mov.l @r15+, r11
mov.l @r15+, r12
mov.l @r15+, r13
mov.l @r15+, r14
#endif
lds.l @r15+, pr
lds.l @r15+, pr /* 7-8: pr and gbr */
ldc.l @r15+, gbr
add #4, r15 /* 9: Skip SP restore */