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Fix assembler errors in generic arm strlen.c.

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Tested using a static version of the strlen libc_test program
on a nexus7 that uses the generic code.

Change-Id: If04d15dcb6c0b18f27f2fefadca5510ed49016c5
This commit is contained in:
Christopher Ferris 2013-07-15 13:55:45 -07:00
parent 67e9f47476
commit d8d10a8994
1 changed files with 13 additions and 4 deletions
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17
libc/arch-arm/generic/bionic/strlen.c
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@ -33,16 +33,16 @@ size_t strlen(const char *s)
{ {
__builtin_prefetch(s); __builtin_prefetch(s);
__builtin_prefetch(s+32); __builtin_prefetch(s+32);
union { union {
const char *b; const char *b;
const uint32_t *w; const uint32_t *w;
uintptr_t i; uintptr_t i;
} u; } u;
// these are some scratch variables for the asm code below // these are some scratch variables for the asm code below
uint32_t v, t; uint32_t v, t;
// initialize the string length to zero // initialize the string length to zero
size_t l = 0; size_t l = 0;
@ -69,42 +69,50 @@ size_t strlen(const char *s)
"sub %[t], %[v], %[mask], lsr #7\n" "sub %[t], %[v], %[mask], lsr #7\n"
"and %[t], %[t], %[mask] \n" "and %[t], %[t], %[mask] \n"
"bics %[t], %[t], %[v] \n" "bics %[t], %[t], %[v] \n"
"it eq \n"
"ldreq %[v], [%[s]], #4 \n" "ldreq %[v], [%[s]], #4 \n"
#if !defined(__OPTIMIZE_SIZE__) #if !defined(__OPTIMIZE_SIZE__)
"bne 1f \n" "bne 1f \n"
"sub %[t], %[v], %[mask], lsr #7\n" "sub %[t], %[v], %[mask], lsr #7\n"
"and %[t], %[t], %[mask] \n" "and %[t], %[t], %[mask] \n"
"bics %[t], %[t], %[v] \n" "bics %[t], %[t], %[v] \n"
"it eq \n"
"ldreq %[v], [%[s]], #4 \n" "ldreq %[v], [%[s]], #4 \n"
"bne 1f \n" "bne 1f \n"
"sub %[t], %[v], %[mask], lsr #7\n" "sub %[t], %[v], %[mask], lsr #7\n"
"and %[t], %[t], %[mask] \n" "and %[t], %[t], %[mask] \n"
"bics %[t], %[t], %[v] \n" "bics %[t], %[t], %[v] \n"
"it eq \n"
"ldreq %[v], [%[s]], #4 \n" "ldreq %[v], [%[s]], #4 \n"
"bne 1f \n" "bne 1f \n"
"sub %[t], %[v], %[mask], lsr #7\n" "sub %[t], %[v], %[mask], lsr #7\n"
"and %[t], %[t], %[mask] \n" "and %[t], %[t], %[mask] \n"
"bics %[t], %[t], %[v] \n" "bics %[t], %[t], %[v] \n"
"it eq \n"
"ldreq %[v], [%[s]], #4 \n" "ldreq %[v], [%[s]], #4 \n"
"bne 1f \n" "bne 1f \n"
"sub %[t], %[v], %[mask], lsr #7\n" "sub %[t], %[v], %[mask], lsr #7\n"
"and %[t], %[t], %[mask] \n" "and %[t], %[t], %[mask] \n"
"bics %[t], %[t], %[v] \n" "bics %[t], %[t], %[v] \n"
"it eq \n"
"ldreq %[v], [%[s]], #4 \n" "ldreq %[v], [%[s]], #4 \n"
"bne 1f \n" "bne 1f \n"
"sub %[t], %[v], %[mask], lsr #7\n" "sub %[t], %[v], %[mask], lsr #7\n"
"and %[t], %[t], %[mask] \n" "and %[t], %[t], %[mask] \n"
"bics %[t], %[t], %[v] \n" "bics %[t], %[t], %[v] \n"
"it eq \n"
"ldreq %[v], [%[s]], #4 \n" "ldreq %[v], [%[s]], #4 \n"
"bne 1f \n" "bne 1f \n"
"sub %[t], %[v], %[mask], lsr #7\n" "sub %[t], %[v], %[mask], lsr #7\n"
"and %[t], %[t], %[mask] \n" "and %[t], %[t], %[mask] \n"
"bics %[t], %[t], %[v] \n" "bics %[t], %[t], %[v] \n"
"it eq \n"
"ldreq %[v], [%[s]], #4 \n" "ldreq %[v], [%[s]], #4 \n"
"bne 1f \n" "bne 1f \n"
"sub %[t], %[v], %[mask], lsr #7\n" "sub %[t], %[v], %[mask], lsr #7\n"
"and %[t], %[t], %[mask] \n" "and %[t], %[t], %[mask] \n"
"bics %[t], %[t], %[v] \n" "bics %[t], %[t], %[v] \n"
"it eq \n"
"ldreq %[v], [%[s]], #4 \n" "ldreq %[v], [%[s]], #4 \n"
#endif #endif
"beq 0b \n" "beq 0b \n"
@ -117,13 +125,14 @@ size_t strlen(const char *s)
"beq 2f \n" "beq 2f \n"
"add %[l], %[l], #1 \n" "add %[l], %[l], #1 \n"
"tst %[v], #0xFF0000 \n" "tst %[v], #0xFF0000 \n"
"it ne \n"
"addne %[l], %[l], #1 \n" "addne %[l], %[l], #1 \n"
"2: \n" "2: \n"
: [l]"=&r"(l), [v]"=&r"(v), [t]"=&r"(t), [s]"=&r"(u.b) : [l]"=&r"(l), [v]"=&r"(v), [t]"=&r"(t), [s]"=&r"(u.b)
: "%[l]"(l), "%[s]"(u.b), [mask]"r"(0x80808080UL) : "%[l]"(l), "%[s]"(u.b), [mask]"r"(0x80808080UL)
: "cc" : "cc"
); );
done: done:
return l; return l;
} }