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[#162] Fix 64bit atomic api issues for 32bit system-part4 #426

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[#162] Fix 64bit atomic api issues for 32bit system-part4 #426

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46 changes: 37 additions & 9 deletions include/click/atomic.hh
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Original file line number Diff line number Diff line change
Expand Up @@ -1015,10 +1015,18 @@ atomic_uint64_t::compare_swap(volatile uint64_t &x, uint64_t expected, uint64_t
return __atomic_compare_exchange(&x,&expected,&desired,0,CLICK_ATOMIC_MEMORDER, CLICK_ATOMIC_MEMORDER)
? expected : x;
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "cmpxchgq %2,%1"
: "=a" (expected), "=m" (x)
: "r" (desired), "0" (expected), "m" (x)
: "cc", "memory");
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "cmpxchgq %2,%1"
: "=a" (expected), "=m" (x)
: "r" (desired), "0" (expected), "m" (x)
: "cc", "memory");
#else
asm volatile (CLICK_ATOMIC_LOCK "cmpxchg8b %1\n\t" // Compare EDX:EAX with [mem], replace with ECX:EBX if equal
: "+A" (expected) //load expected into EAX:EDX
: "m" (x), // preload memory value to compare.
"b" ((uint32_t)desired), "c"((uint32_t) (desired>>32))
: "memory");
#endif
return expected;
#elif CLICK_LINUXMODULE && defined(cmpxchg)
return cmpxchg(&x, expected, desired);
Expand Down Expand Up @@ -1063,11 +1071,31 @@ atomic_uint64_t::fetch_and_add(uint64_t delta)
#if CLICK_ATOMIC_BUILTINS
return __atomic_fetch_add(&_val, delta, CLICK_ATOMIC_MEMORDER);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "xaddq %0,%1"
: "=r" (delta), "=m" (CLICK_ATOMIC_VAL)
: "0" (delta), "m" (CLICK_ATOMIC_VAL)
: "cc");
return delta;
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "xaddq %0,%1"
: "=r" (delta), "=m" (CLICK_ATOMIC_VAL)
: "0" (delta), "m" (CLICK_ATOMIC_VAL)
: "cc");
return delta;
#else
uint32_t old_lo, old_hi;
asm volatile (
"1:\n\t"
"movl (%2), %%eax\n\t" // Load old low 32 bits
"movl 4(%2), %%edx\n\t" // Load old high 32 bits
"movl %%eax, %%ebx\n\t" // Copy low to ebx (new low)
"movl %%edx, %%ecx\n\t" // Copy high to ecx (new high)
"addl %3, %%ebx\n\t" // new low += delta low
"adcl %4, %%ecx\n\t" // new high += delta high + carry
CLICK_ATOMIC_LOCK "cmpxchg8b (%2)\n\t" // atomic cmpxchg8b
"jnz 1b\n\t" // if fail, retry
"movl %%eax, %0\n\t" // store old low
"movl %%edx, %1\n\t" // store old high
: "+a" (old_lo), "+d" (old_hi)
: "r" (&_val), "r" ((uint32_t)delta), "r" ((uint32_t)(delta >> 3))
: "ebx", "memory");
return (static_cast<uint64_t>(old_hi) << 32) | old_lo;
#endif
#elif CLICK_LINUXMODULE && HAVE_LINUX_ATOMIC_ADD_RETURN
return atomic64_add_return(&_val, delta) - delta;
#elif CLICK_LINUXMODULE
Expand Down
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