diff options
Diffstat (limited to 'newlib/libc/machine/arm/strcmp.c')
| -rw-r--r-- | newlib/libc/machine/arm/strcmp.c | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/newlib/libc/machine/arm/strcmp.c b/newlib/libc/machine/arm/strcmp.c index d34bae094..0d0c3d363 100644 --- a/newlib/libc/machine/arm/strcmp.c +++ b/newlib/libc/machine/arm/strcmp.c @@ -192,6 +192,7 @@ strcmp_unaligned(const char* s1, const char* s2) } \ if (__builtin_expect(((w1 - b1) & ~w1) & (b1 << 7), 0)) \ { \ + /* See comment in assembler below re syndrome on big-endian */\ if ((((w1 - b1) & ~w1) & (b1 << 7)) & mask) \ w2 RSHIFT= shift; \ else \ @@ -319,12 +320,22 @@ strcmp_unaligned(const char* s1, const char* s2) "b 8f\n" "5:\n\t" - "bics r3, r3, #"MSB"\n\t" +#ifdef __ARMEB__ + /* The syndrome value may contain false ones if the string ends + with the bytes 0x01 0x00 */ + "tst w1, #0xff000000\n\t" + "itt ne\n\t" + "tstne w1, #0x00ff0000\n\t" + "tstne w1, #0x0000ff00\n\t" + "beq 7f\n\t" +#else + "bics r3, r3, #0xff000000\n\t" "bne 7f\n\t" +#endif "ldrb w2, [wp2]\n\t" SHFT2LSB" t1, w1, #24\n\t" #ifdef __ARMEB__ - SHFT2LSB" w2, w2, #24\n\t" + "lsl w2, w2, #24\n\t" #endif "b 8f\n" @@ -353,12 +364,21 @@ strcmp_unaligned(const char* s1, const char* s2) "b 2b\n" "5:\n\t" - SHFT2MSB"s r3, r3, #16\n\t" +#ifdef __ARMEB__ + /* The syndrome value may contain false ones if the string ends + with the bytes 0x01 0x00 */ + "tst w1, #0xff000000\n\t" + "it ne\n\t" + "tstne w1, #0x00ff0000\n\t" + "beq 7f\n\t" +#else + "lsls r3, r3, #16\n\t" "bne 7f\n\t" +#endif "ldrh w2, [wp2]\n\t" SHFT2LSB" t1, w1, #16\n\t" #ifdef __ARMEB__ - SHFT2LSB" w2, w2, #16\n\t" + "lsl w2, w2, #16\n\t" #endif "b 8f\n" @@ -390,8 +410,10 @@ strcmp_unaligned(const char* s1, const char* s2) SHFT2LSB" w2, w2, #24\n\t" "b 8f\n" "5:\n\t" - "tst r3, #128\n\t" - "bne 7f\n\t" + /* The syndrome value may contain false ones if the string ends + with the bytes 0x01 0x00 */ + "tst w1, #"LSB"\n\t" + "beq 7f\n\t" "ldr w2, [wp2], #4\n" "6:\n\t" SHFT2LSB" t1, w1, #8\n\t" |