// *****************************************************************
//
//               The Compcert verified compiler
//
//           Xavier Leroy, INRIA Paris-Rocquencourt
//
// Copyright (c) 2013 Institut National de Recherche en Informatique et
//  en Automatique.
//
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// *********************************************************************

// Helper functions for 64-bit integer arithmetic.  IA32 version.
	
#include "sysdeps.h"

// Shift left

// Note: IA32 shift instructions treat their amount (in %cl) modulo 32

FUNCTION(__i64_shl)
        movl 12(%esp), %ecx             // ecx = shift amount, treated mod 64
        testb $32, %cl
        jne 1f
  // shift amount < 32  
        movl 4(%esp), %eax
        movl 8(%esp), %edx
        shldl %cl, %eax, %edx           // edx = high(XH:XL << amount)
        shll %cl, %eax                  // eax = XL << amount
        ret
  // shift amount >= 32
1:      movl 4(%esp), %edx
        shll %cl, %edx                  // edx = XL << (amount - 32)
        xorl %eax, %eax                 // eax = 0
        ret
ENDFUNCTION(__i64_shl)