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1// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.2// See https://llvm.org/LICENSE.txt for license information.3// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception4 5#include "../assembly.h"6 7// di_int __ashrdi3(di_int input, int count);8 9#ifdef __i386__10#ifdef __SSE2__11 12.text13.balign 414DEFINE_COMPILERRT_FUNCTION(__ashrdi3)15 movd 12(%esp), %xmm2 // Load count16 movl 8(%esp), %eax17#ifndef TRUST_CALLERS_USE_64_BIT_STORES18 movd 4(%esp), %xmm019 movd 8(%esp), %xmm120 punpckldq %xmm1, %xmm0 // Load input21#else22 movq 4(%esp), %xmm0 // Load input23#endif24 25 psrlq %xmm2, %xmm0 // unsigned shift input by count26 27 testl %eax, %eax // check the sign-bit of the input28 jns 1f // early out for positive inputs29 30 // If the input is negative, we need to construct the shifted sign bit31 // to or into the result, as xmm does not have a signed right shift.32 pcmpeqb %xmm1, %xmm1 // -1ULL33 psrlq $58, %xmm1 // 0x3f34 pandn %xmm1, %xmm2 // 63 - count35 pcmpeqb %xmm1, %xmm1 // -1ULL36 psubq %xmm1, %xmm2 // 64 - count37 psllq %xmm2, %xmm1 // -1 << (64 - count) = leading sign bits38 por %xmm1, %xmm039 40 // Move the result back to the general purpose registers and return411: movd %xmm0, %eax42 psrlq $32, %xmm043 movd %xmm0, %edx44 ret45END_COMPILERRT_FUNCTION(__ashrdi3)46 47#else // Use GPRs instead of SSE2 instructions, if they aren't available.48 49.text50.balign 451DEFINE_COMPILERRT_FUNCTION(__ashrdi3)52 movl 12(%esp), %ecx // Load count53 movl 8(%esp), %edx // Load high54 movl 4(%esp), %eax // Load low55 56 testl $0x20, %ecx // If count >= 3257 jnz 1f // goto 158 59 shrdl %cl, %edx, %eax // right shift low by count60 sarl %cl, %edx // right shift high by count61 ret62 631: movl %edx, %eax // Move high to low64 sarl $31, %edx // clear high65 sarl %cl, %eax // shift low by count - 3266 ret67END_COMPILERRT_FUNCTION(__ashrdi3)68 69#endif // __SSE2__70#endif // __i386__71 72NO_EXEC_STACK_DIRECTIVE73 74