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/* libs/opengles/arch-mips/fixed_asm.S
**
** Copyright 2012, The Android Open Source Project
**
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
**
** http://www.apache.org/licenses/LICENSE-2.0
**
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*/
.text
.align
/*
* this version rounds-to-nearest and saturates numbers
* outside the range (but not NaNs).
*/
.global gglFloatToFixed
.ent gglFloatToFixed
.type gglFloatToFixed, @function
gglFloatToFixed:
#if !defined(__mips_soft_float)
mfc1 $a0,$f12
#endif
srl $t0,$a0,31 /* t0 <- sign bit */
srl $t1,$a0,23
andi $t1,$t1,0xff /* get the e */
li $t2,0x8e
subu $t1,$t2,$t1 /* t1=127+15-e */
blez $t1,0f /* t1<=0? */
sll $t2,$a0,8 /* mantissa<<8 */
lui $t3,0x8000
or $t2,$t2,$t3 /* add the missing 1 */
subu $t1,$t1,1
srl $v0,$t2,$t1
sltiu $t3,$t1,32 /* t3=1 if t1<32, else t3=0. t1>=32 means the float value is too small. */
andi $t4,$v0,0x1
srl $v0,$v0,1 /* scale to 16.16 */
addu $v0,$v0,$t4 /* round-to-nearest */
subu $t2,$zero,$v0
movn $v0,$t2,$t0 /* if negative? */
or $t1,$a0,$zero /* a0=0? */
movz $v0,$zero,$t1
movz $v0,$zero,$t3 /* t3=0 then res=0 */
jr $ra
0:
lui $t1,0x8000
and $v0,$a0,$t1 /* keep only the sign bit */
li $t1,0x7fffffff
movz $v0,$t1,$t0 /* positive, maximum value */
jr $ra
.end gglFloatToFixed
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