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| author | Roland McGrath <roland@hack.frob.com> | 2015-03-19 12:45:24 -0700 |
|---|---|---|
| committer | Roland McGrath <roland@hack.frob.com> | 2015-03-19 12:45:24 -0700 |
| commit | 298e5d56dca199aea2c18ef27dd33bd82c879ee4 (patch) | |
| tree | c30e0d64a0529f470c6f60ea91e73cc7a0f842d9 | |
| parent | becb26b84bfe4d3273c4e2d4e7684dfbbf7c6bcd (diff) | |
| download | glibc-298e5d56dca199aea2c18ef27dd33bd82c879ee4.tar glibc-298e5d56dca199aea2c18ef27dd33bd82c879ee4.tar.gz glibc-298e5d56dca199aea2c18ef27dd33bd82c879ee4.tar.bz2 glibc-298e5d56dca199aea2c18ef27dd33bd82c879ee4.zip | |
ARM: Fix memcpy & memmove for [ARM_ALWAYS_BX]
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | sysdeps/arm/memcpy.S | 16 | ||||
| -rw-r--r-- | sysdeps/arm/memmove.S | 16 |
3 files changed, 32 insertions, 6 deletions
@@ -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. diff --git a/sysdeps/arm/memcpy.S b/sysdeps/arm/memcpy.S index 0602d992f0..3e41ea6f61 100644 --- a/sysdeps/arm/memcpy.S +++ b/sysdeps/arm/memcpy.S @@ -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 diff --git a/sysdeps/arm/memmove.S b/sysdeps/arm/memmove.S index f8a4eff2a4..dde877e5f3 100644 --- a/sysdeps/arm/memmove.S +++ b/sysdeps/arm/memmove.S @@ -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]! |