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#include <stdio.h>

int test_func(void);

volatile long count;

int main(int argc, char *argv[]) {

	long i;

	for (i=0; i<500000000; ++i) {
		test_func();
	}
	printf("count=%ld\n", count);
}

int test_func() {

	++count;
}

Code: Select all

_main:
0000000100000e8c	pushq	%rbp
0000000100000e8d	movq	%rsp,%rbp
0000000100000e90	subq	$0x20,%rsp
0000000100000e94	movl	%edi,0xec(%rbp)
0000000100000e97	movq	%rsi,0xe0(%rbp)
0000000100000e9b	movq	$0x00000000,0xf8(%rbp)
0000000100000ea3	jmp	0x00000eae
0000000100000ea5	callq	0x00000ed5
0000000100000eaa	incq	0xf8(%rbp)
0000000100000eae	cmpq	$0x1dcd64ff,0xf8(%rbp)
0000000100000eb6	jle	0x00000ea5
0000000100000eb8	leaq	0x000001a9(%rip),%rax
0000000100000ebf	movq	(%rax),%rsi
0000000100000ec2	leaq	0x0000005b(%rip),%rdi
0000000100000ec9	movl	$0x00000000,%eax
0000000100000ece	callq	0x00000efa
0000000100000ed3	leave
0000000100000ed4	ret
_test_func:
0000000100000ed5	pushq	%rbp
0000000100000ed6	movq	%rsp,%rbp
0000000100000ed9	leaq	0x00000188(%rip),%rax
0000000100000ee0	movq	(%rax),%rax
0000000100000ee3	leaq	0x01(%rax),%rdx
0000000100000ee7	leaq	0x0000017a(%rip),%rax
0000000100000eee	movq	%rdx,(%rax)
0000000100000ef1	leave
0000000100000ef2	ret

Code: Select all

#include <time.h>
#include <iostream>
using namespace std;


int main()
{
	unsigned long long total = 0;
	unsigned long long low = 0xFFFFFFFFFFFFFFF;
	unsigned long long high = 0; 

	for (int i = 0; i < 1000; i++)
	{
		clock_t start = clock();

		_asm
		{
			push ecx
			mov ecx, 11000000
	
			callfunc:
				call function
				sub ecx, 1
				jnz callfunc
				jmp done

			function:
				ret
			done:
				pop ecx
		}

		clock_t end = clock();
		total += end - start;
		if (low > (end - start))
			low = end - start;
		else if (high < (end - start))
			high = end - start;
	}

	cout << "Total: " << total << endl;
	cout << "Average: " << (double)total / 1000.0 << endl;
	cout << "Low: " << low << endl;
	cout << "High: " << high << endl;

	return 0;
}

Code: Select all

INSTRUCTION								OPCODE	DECODE TYPE	MIN. LATENCY (Where 2 values 32bit-64bit)
CALL disp16/32 (near, displacement)				E8h	VectorPath	3
CALL pntr16:16/32 (far, direct, no CPL change)		9Ah	VectorPath	33
CALL pntr16:16/32 (far, direct, CPL change)		9Ah	VectorPath	150
RET near imm16 							C2h	VectorPath 	5
RET near 									C3h	Double 		5
RET far imm16 (no CPL change) 					CAh 	VectorPath 	31–44
RET far imm16 (CPL change) 					CAh 	VectorPath 	57-72
RET far (no CPL change) 						CBh 	VectorPath 	31–44
RET far (CPL change) 						CBh 	VectorPath 	57-72

INT imm8 (CPL change) 						CDh	VectorPath	91–112
IRET, IRETD, IRETQ (from 64-bit to 64-bit) 		CFh	VectorPath	91
IRET, IRETD, IRETQ (from 64-bit to 32-bit) 		CFh	VectorPath	111
IRET, IRETD, IRETQ (from 64-bit to 32-bit)	... no data

MOV sreg, mreg16/32/64						8Eh 	VectorPath 	8
MOV sreg, mem16 							8Eh 	VectorPath 	10

SYSCALL 									0Fh 05h	VectorPath	27
SYSENTER 									0Fh 34h	VectorPath 	~
SYSEXIT 									0Fh 35h	VectorPath 	~
SYSRET 									0Fh 07h	VectorPath 	35