FreeCalypso > hg > freecalypso-tools
annotate target-utils/libc/memcpy.S @ 965:2969032bdfac
fcup-smsend[mult]: fix buglet in K&R C NULL pointer passing
The only 100% safe way to pass a NULL pointer as a function argument
in K&R C is to cast 0 to a pointer type; failing to do so may cause
mysterious bugs (invalid stack frames or garbage in argument registers)
on 64-bit machines. This issue has already been fixed in most of
FC host tools, but I just found some missed spots: passing of NULL UDH
to PDU encoding functions in fcup-smsend[mult] in the case of single
(not concatenated) SMS.
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Fri, 01 Sep 2023 07:33:51 +0000 |
parents | f4619719834f |
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rev | line source |
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f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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1 .text |
f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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2 .code 32 |
f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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3 .globl memcpy |
f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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4 memcpy: |
f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
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5 1: subs r2, r2, #1 |
f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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6 ldrcsb r3, [r1], #1 |
f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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7 strcsb r3, [r0], #1 |
f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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8 bhi 1b |
f4619719834f
target-utils/libc: our own memcpy assembly implementation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff
changeset
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9 bx lr |