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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 __ashldi3(di_int input, int count);8 9// This routine has some extra memory traffic, loading the 64-bit input via two10// 32-bit loads, then immediately storing it back to the stack via a single 64-bit11// store. This is to avoid a write-small, read-large stall.12// However, if callers of this routine can be safely assumed to store the argument13// via a 64-bt store, this is unnecessary memory traffic, and should be avoided.14// It can be turned off by defining the TRUST_CALLERS_USE_64_BIT_STORES macro.15 16#ifdef __i386__17#ifdef __SSE2__18 19.text20.balign 421DEFINE_COMPILERRT_FUNCTION(__ashldi3)22 movd 12(%esp), %xmm2 // Load count23#ifndef TRUST_CALLERS_USE_64_BIT_STORES24 movd 4(%esp), %xmm025 movd 8(%esp), %xmm126 punpckldq %xmm1, %xmm0 // Load input27#else28 movq 4(%esp), %xmm0 // Load input29#endif30 psllq %xmm2, %xmm0 // shift input by count31 movd %xmm0, %eax32 psrlq $32, %xmm033 movd %xmm0, %edx34 ret35END_COMPILERRT_FUNCTION(__ashldi3)36 37#else // Use GPRs instead of SSE2 instructions, if they aren't available.38 39.text40.balign 441DEFINE_COMPILERRT_FUNCTION(__ashldi3)42 movl 12(%esp), %ecx // Load count43 movl 8(%esp), %edx // Load high44 movl 4(%esp), %eax // Load low45 46 testl $0x20, %ecx // If count >= 3247 jnz 1f // goto 148 shldl %cl, %eax, %edx // left shift high by count49 shll %cl, %eax // left shift low by count50 ret51 521: movl %eax, %edx // Move low to high53 xorl %eax, %eax // clear low54 shll %cl, %edx // shift high by count - 3255 ret56END_COMPILERRT_FUNCTION(__ashldi3)57 58#endif // __SSE2__59#endif // __i386__60 61NO_EXEC_STACK_DIRECTIVE62 63