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xtensa: use "m" constraint instead of "a" in bitops.h assembly 

Use "m" constraint instead of "r" for the address, as "m" allows
compiler to access adjacent locations using base + offset, while "r"
requires updating the base register every time.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Max Filippov 2019-10-15 22:17:33 -07:00
parent e444917019
commit 5bf67094a3
1 changed files with 10 additions and 8 deletions
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18
arch/xtensa/include/asm/bitops.h
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@ -150,13 +150,14 @@ static inline void op##_bit(unsigned int bit, volatile unsigned long *p)\
p += bit >> 5; \
\
__asm__ __volatile__( \
"1: l32i %[value], %[addr], 0\n" \
"1: l32i %[value], %[mem]\n" \
" wsr %[value], scompare1\n" \
" "insn" %[tmp], %[value], %[mask]\n" \
" s32c1i %[tmp], %[addr], 0\n" \
" s32c1i %[tmp], %[mem]\n" \
" bne %[tmp], %[value], 1b\n" \
: [tmp] "=&a" (tmp), [value] "=&a" (value) \
: [mask] "a" (inv mask), [addr] "a" (p) \
: [tmp] "=&a" (tmp), [value] "=&a" (value), \
[mem] "+m" (*p) \
: [mask] "a" (inv mask) \
: "memory"); \
}
@ -170,13 +171,14 @@ test_and_##op##_bit(unsigned int bit, volatile unsigned long *p) \
p += bit >> 5; \
\
__asm__ __volatile__( \
"1: l32i %[value], %[addr], 0\n" \
"1: l32i %[value], %[mem]\n" \
" wsr %[value], scompare1\n" \
" "insn" %[tmp], %[value], %[mask]\n" \
" s32c1i %[tmp], %[addr], 0\n" \
" s32c1i %[tmp], %[mem]\n" \
" bne %[tmp], %[value], 1b\n" \
: [tmp] "=&a" (tmp), [value] "=&a" (value) \
: [mask] "a" (inv mask), [addr] "a" (p) \
: [tmp] "=&a" (tmp), [value] "=&a" (value), \
[mem] "+m" (*p) \
: [mask] "a" (inv mask) \
: "memory"); \
\
return tmp & mask; \