1// This file is dual licensed under the MIT and the University of Illinois Open 2// Source Licenses. See LICENSE.TXT for details. 3 4#include "../assembly.h" 5 6// di_int __ashldi3(di_int input, int count); 7 8// This routine has some extra memory traffic, loading the 64-bit input via two 9// 32-bit loads, then immediately storing it back to the stack via a single 64-bit 10// store. This is to avoid a write-small, read-large stall. 11// However, if callers of this routine can be safely assumed to store the argument 12// via a 64-bt store, this is unnecessary memory traffic, and should be avoided. 13// It can be turned off by defining the TRUST_CALLERS_USE_64_BIT_STORES macro. 14 15#ifdef __i386__ 16#ifdef __SSE2__ 17 18.text 19.balign 4 20DEFINE_COMPILERRT_FUNCTION(__ashldi3) 21 movd 12(%esp), %xmm2 // Load count 22#ifndef TRUST_CALLERS_USE_64_BIT_STORES 23 movd 4(%esp), %xmm0 24 movd 8(%esp), %xmm1 25 punpckldq %xmm1, %xmm0 // Load input 26#else 27 movq 4(%esp), %xmm0 // Load input 28#endif 29 psllq %xmm2, %xmm0 // shift input by count 30 movd %xmm0, %eax 31 psrlq $32, %xmm0 32 movd %xmm0, %edx 33 ret 34END_COMPILERRT_FUNCTION(__ashldi3) 35 36#else // Use GPRs instead of SSE2 instructions, if they aren't available. 37 38.text 39.balign 4 40DEFINE_COMPILERRT_FUNCTION(__ashldi3) 41 movl 12(%esp), %ecx // Load count 42 movl 8(%esp), %edx // Load high 43 movl 4(%esp), %eax // Load low 44 45 testl $0x20, %ecx // If count >= 32 46 jnz 1f // goto 1 47 shldl %cl, %eax, %edx // left shift high by count 48 shll %cl, %eax // left shift low by count 49 ret 50 511: movl %eax, %edx // Move low to high 52 xorl %eax, %eax // clear low 53 shll %cl, %edx // shift high by count - 32 54 ret 55END_COMPILERRT_FUNCTION(__ashldi3) 56 57#endif // __SSE2__ 58#endif // __i386__ 59 60NO_EXEC_STACK_DIRECTIVE 61 62