#define INSTR movslq #define NINST 64 #define N edi #define i r8d .intel_syntax noprefix .globl ninst .data ninst: .long NINST .align 32 PI: .long 0xf01b866e, 0x400921f9, 0xf01b866e, 0x400921f9, 0xf01b866e, 0x400921f9, 0xf01b866e, 0x400921f9, 0xf01b866e, 0x400921f9, 0xf01b866e, 0x400921f9, 0xf01b866e, 0x400921f9, 0xf01b866e, 0x400921f9 .text .globl latency .type latency, @function .align 32 latency: push rbp mov rbp, rsp xor i, i test N, N jle done # create DP 1.0 vpcmpeqw xmm0, xmm0, xmm0 # all ones vpsllq xmm0, xmm0, 54 # logical left shift: 11111110..0 (54=64-(10-1)) vpsrlq xmm0, xmm0, 2 # logical right shift: 1 bit for sign; leading mantissa bit is zero push rax push rbx push rcx push rdx push r9 push r10 push r11 push r12 push r13 push r14 push r15 xor rax, rax xor rbx, rbx xor rcx, rcx xor rdx, rdx xor r9, r9 xor r10, r10 xor r11, r11 xor r12, r12 xor r13, r13 xor r14, r14 xor r15, r15 # copy DP 1.0 vmovq rax, xmm0 vmovq rbx, xmm0 # Create DP 2.0 add rbx, rax # Create DP 0.5 div rax movq rcx, rax vmovq rax, xmm0 loop: inc i INSTR rdx, eax INSTR r9, ebx INSTR r10, ecx INSTR r11, eax INSTR r12, ebx INSTR r13, ecx INSTR r14, eax INSTR r15, ebx INSTR rdx, ecx INSTR r9, eax INSTR r10, ebx INSTR r11, ecx INSTR r12, eax INSTR r13, ebx INSTR r14, ecx INSTR r15, eax INSTR rdx, ebx INSTR r9, ecx INSTR r10, eax INSTR r11, ebx INSTR r12, ecx INSTR r13, eax INSTR r14, ebx INSTR r15, ecx INSTR rdx, eax INSTR r9, ebx INSTR r10, ecx INSTR r11, eax INSTR r12, ebx INSTR r13, ecx INSTR r14, eax INSTR r15, ebx INSTR rdx, ecx INSTR r9, eax INSTR r10, ebx INSTR r11, ecx INSTR r12, eax INSTR r13, ebx INSTR r14, ecx INSTR r15, eax INSTR rdx, ebx INSTR r9, ecx INSTR r10, eax INSTR r11, ebx INSTR r12, ecx INSTR r13, eax INSTR r14, ebx INSTR r15, ecx INSTR rdx, eax INSTR r9, ebx INSTR r10, ecx INSTR r11, eax INSTR r12, ebx INSTR r13, ecx INSTR r14, eax INSTR r15, ebx INSTR rdx, ecx INSTR r9, eax INSTR r10, ebx INSTR r11, ecx INSTR r12, eax INSTR r13, ebx INSTR r14, ecx INSTR r15, eax cmp i, N jl loop pop r15 pop r14 pop r13 pop r12 pop r11 pop r10 pop r9 pop rdx pop rcx pop rbx pop rax done: mov rsp, rbp pop rbp ret .size latency, .-latency