ARM: Fix memcpy & memmove for [ARM_ALWAYS_BX]

This commit is contained in:
Roland McGrath 2015-03-19 12:45:24 -07:00
parent becb26b84b
commit 298e5d56dc
3 changed files with 32 additions and 6 deletions

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@ -1,3 +1,9 @@
2015-03-19 Roland McGrath <roland@hack.frob.com>
* sysdeps/arm/memcpy.S [ARM_ALWAYS_BX]: Fix computed-jump calculations
to account for alignment padding.
* sysdeps/arm/memmove.S: Likewise.
2015-03-19 Chris Metcalf <cmetcalf@ezchip.com>
* sysdeps/unix/sysv/linux/generic/README: New file.

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@ -125,7 +125,12 @@ ENTRY(memcpy)
push {r10}
cfi_adjust_cfa_offset (4)
cfi_rel_offset (r10, 0)
add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
0: add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
/* If alignment is not perfect, then there will be some
padding (nop) instructions between this BX and label 6.
The computation above assumed that two instructions
later is exactly the right spot. */
add r10, #(6f - (0b + PC_OFS))
bx r10
#endif
.p2align ARM_BX_ALIGN_LOG2
@ -156,11 +161,16 @@ ENTRY(memcpy)
add pc, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
nop
#else
add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
0: add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
/* If alignment is not perfect, then there will be some
padding (nop) instructions between this BX and label 66.
The computation above assumed that two instructions
later is exactly the right spot. */
add r10, #(66f - (0b + PC_OFS))
bx r10
#endif
.p2align ARM_BX_ALIGN_LOG2
nop
66: nop
.p2align ARM_BX_ALIGN_LOG2
sfi_breg r0, \
str r3, [\B], #4

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@ -141,7 +141,12 @@ ENTRY(memmove)
push {r10}
cfi_adjust_cfa_offset (4)
cfi_rel_offset (r10, 0)
add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
0: add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
/* If alignment is not perfect, then there will be some
padding (nop) instructions between this BX and label 6.
The computation above assumed that two instructions
later is exactly the right spot. */
add r10, #(6f - (0b + PC_OFS))
bx r10
#endif
.p2align ARM_BX_ALIGN_LOG2
@ -172,11 +177,16 @@ ENTRY(memmove)
add pc, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
nop
#else
add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
0: add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
/* If alignment is not perfect, then there will be some
padding (nop) instructions between this BX and label 66.
The computation above assumed that two instructions
later is exactly the right spot. */
add r10, #(66f - (0b + PC_OFS))
bx r10
#endif
.p2align ARM_BX_ALIGN_LOG2
nop
66: nop
.p2align ARM_BX_ALIGN_LOG2
sfi_breg r0, \
str r3, [\B, #-4]!