Documentation
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#if defined(__arm__)

#include "SKP_Silk_AsmPreproc.h"
#if EMBEDDED_ARM>=5

	VARDEF val_lz, r1
	VARDEF val_shift, r2
	VARDEF val_frac, r3

	VARDEF val_ret1, r1
	VARDEF val_128minfrac, r2
	VARDEF val_mul_ret, r0
	VARDEF val_add_ret, r3
	VARDEF const1, r1

.globl	SYM(SKP_Silk_lin2log)
SYM(SKP_Silk_lin2log):
	stmdb	sp!,  {r4-r5, fp, ip, lr}
	add		fp, sp, #16
	
	clz		val_lz, r0											/*lz*/
	cmp		val_lz, #24
	sub		val_shift, val_lz, #24
#ifdef _WINRT
	bge		LR(0, f)
	rsb		val_shift, val_lz, #24
	mov		val_frac, r0, asr val_shift
	b		LR(1, f)
L(0)	
	mov		val_frac, r0, lsl val_shift
L(1)	
#else	
	rsblt	val_shift, val_lz, #24
	movlt	val_frac, r0, asr val_shift
	movge	val_frac, r0, lsl val_shift
#endif	
	and		val_frac, val_frac, #0x7F							/*frac_Q7*/
	
	rsb		val_ret1, val_lz, #31								/*31-lz*/
	rsb		val_128minfrac, val_frac, #128						/*128-frac_Q7*/
	mov		val_ret1, val_ret1, lsl #7
	mul		val_mul_ret, val_frac, val_128minfrac				/*SKP_MUL(frac_Q7, 128 - frac_Q7)*/
	add		val_add_ret, val_ret1, val_frac
	mov		const1, #179
	smlawb	r0, val_mul_ret, const1, val_add_ret
	
	ldmia	sp!,  {r4-r5, fp, ip, pc}
	
#elif EMBEDDED_ARM>=4
	VARDEF val_lz, r0
	VARDEF val_in, r4
	VARDEF val_shift, r1
	VARDEF val_frac, r2
	VARDEF val_ret1, r1
	VARDEF val_128minfrac, r3
	VARDEF val_mul_ret, r3
	VARDEF tmp0, r4
	VARDEF const1, r2
	VARDEF val_ret, r0

.globl	SYM(SKP_Silk_lin2log)
SYM(SKP_Silk_lin2log):
	stmdb	sp!,  {r4-r5, fp, ip, lr}
	add		fp, sp, #16

	mov		val_in, r0
	bl		SYM(SKP_Silk_CLZ32)
	cmp		val_lz, #24
	sub		val_shift, val_lz, #24
	rsblt	val_shift, val_lz, #24
	movlt	val_frac, val_in, asr val_shift
	movge	val_frac, val_in, lsl val_shift
	and		val_frac, val_frac, #0x7F							/*frac_Q7*/
	
	rsb		val_ret1, val_lz, #31								/*31-lz*/
	rsb		val_128minfrac, val_frac, #128							/*128-frac_Q7*/
	mov		val_ret1, val_ret1, lsl #7
	mul		val_mul_ret, val_frac, val_128minfrac								/*SKP_MUL(frac_Q7, 128 - frac_Q7)*/
	add		val_ret, val_ret1, val_frac
	mov		tmp0, #0
	mov		const1, #0xB30000
	smlal	tmp0, val_ret, val_mul_ret, const1
	
	ldmia	sp!,  {r4-r5, fp, ip, pc}
#endif
	END
#endif