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      1 // This file is distributed under the University of Illinois Open Source
      2 // License. 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 .align 4
     20 DEFINE_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
     34 
     35 #else // Use GPRs instead of SSE2 instructions, if they aren't available.
     36 
     37 .text
     38 .align 4
     39 DEFINE_COMPILERRT_FUNCTION(__ashldi3)
     40 	movl	  12(%esp),		%ecx	// Load count
     41 	movl	   8(%esp),		%edx	// Load high
     42 	movl	   4(%esp),		%eax	// Load low
     43 
     44 	testl		$0x20,		%ecx	// If count >= 32
     45 	jnz		1f			//    goto 1
     46 	shldl		%cl, %eax,	%edx	// left shift high by count
     47 	shll		%cl,		%eax	// left shift low by count
     48 	ret
     49 
     50 1:	movl		%eax,		%edx	// Move low to high
     51 	xorl		%eax,		%eax	// clear low
     52 	shll		%cl,		%edx	// shift high by count - 32
     53 	ret
     54 
     55 #endif // __SSE2__
     56 #endif // __i386__
     57