我在使用编程时发现浮点运算在debug 模式和release模式所有的时间相差太大，不知问题出在什么地方，请高手给以解答，谢谢。
我的程序中有这个函数：
void timetest()
{
float fii_r,fuu_r,fuu_x,fii_x,fu_f,ii_x;
int k;
fii_r=5678;
fuu_x=3478;
fii_x=7896;
fuu_r=3456.00;
while(1)
{
fu_f =sqrt(fuu_r); //debug模式下用时 1us，release模式下，代码考入RAM运行 用时 35us
GpioDataRegs.GPASET.bit.GPIO17 = 1;
fu_f =-703*(fuu_r*fii_r+fuu_x*fii_x)/(fii_r*fii_r+fii_x*fii_x); //debug模式下用时 2.5us，release模式下，代码考入RAM运行 用时 12us
GpioDataRegs.GPACLEAR.bit.GPIO17 = 1;
}
}
map文件如下：
.text 0 00328000 00001b8e RUN ADDR = 00009000
00328000 000014de Example_2833xGpioToggle.obj (.text)
003294de 0000018b DSP2833x_DefaultIsr.obj (.text)
00329669 0000010b DSP2833x_SysCtrl.obj (.text)
00329774 000000b2 dsp28335_xintf.obj (.text)
00329826 00000083 rts2800_ml.lib : fs_div.obj (.text)
003298a9 00000078 : fs_add.obj (.text)
00329921 0000005a : fs_mpy.obj (.text)
0032997b 00000050 : sqrt.obj (.text)
003299cb 00000044 : boot.obj (.text)
00329a0f 00000041 : ldexp.obj (.text)
00329a50 00000028 DSP2833x_PieCtrl.obj (.text)
00329a78 00000025 rts2800_ml.lib : fs_toi.obj (.text)
00329a9d 00000022 : i_div.obj (.text)
00329abf 00000020 DSP2833x_PieVect.obj (.text)
00329adf 0000001d rts2800_ml.lib : fs_tou.obj (.text)
00329afc 0000001b : args_main.obj (.text)
00329b17 0000001a : i_tofs.obj (.text)
00329b31 00000019 : exit.obj (.text)
00329b4a 00000017 : fs_cmp.obj (.text)
00329b61 00000015 DSP2833x_MemCopy.obj (.text)
00329b76 0000000b rts2800_ml.lib : u_div.obj (.text)
00329b81 00000009 : _lock.obj (.text)
00329b8a 00000004 DSP2833x_usDelay.obj (.text)
.econst 0 00338000 00000400
00338000 00000100 DSP2833x_PieVect.obj (.econst)
00338100 00000100 Example_2833xGpioToggle.obj (.econst:_auchCRCHi16)
00338200 00000100 Example_2833xGpioToggle.obj (.econst:_auchCRCLo16)
00338300 00000080 Example_2833xGpioToggle.obj (.econst:_fcos)
00338380 00000080 Example_2833xGpioToggle.obj (.econst:_fsin)
.cinit 0 00338400 00000032 RUN ADDR = 0000ab8e
00338400 00000018 Example_2833xGpioToggle.obj (.cinit)
00338418 0000000a rts2800_ml.lib : _lock.obj (.cinit)
00338422 0000000a : exit.obj (.cinit)
0033842c 00000004 : errno.obj (.cinit)
00338430 00000002 --HOLE-- [fill = 0]
00009ce7 _timetest //temitest 函数地址
下面是cmd文件
MEMORY
{
PAGE 0: /* Program Memory */
/* Memory (RAM/FLASH/OTP) blocks can be moved to PAGE1 for data allocation */
ZONE0 : origin = 0x004000, length = 0x001000 /* XINTF zone 0 */
RAML0 : origin = 0x008000, length = 0x001000 /* on-chip RAM block L0 */
RAML112 : origin = 0x009000, length = 0x003000 /* on-chip RAM block L1 */
ZONE6 : origin = 0x0100000, length = 0x100000 /* XINTF zone 6 */
ZONE7A : origin = 0x0200000, length = 0x00FC00 /* XINTF zone 7 - program space */
FLASHH : origin = 0x300000, length = 0x008000 /* on-chip FLASH */
FLASHG : origin = 0x308000, length = 0x008000 /* on-chip FLASH */
FLASHF : origin = 0x310000, length = 0x008000 /* on-chip FLASH */
FLASHE : origin = 0x318000, length = 0x008000 /* on-chip FLASH */
FLASHD : origin = 0x320000, length = 0x008000 /* on-chip FLASH */
FLASHC : origin = 0x328000, length = 0x008000 /* on-chip FLASH */
FLASHA : origin = 0x338000, length = 0x007F80 /* on-chip FLASH */
CSM_RSVD : origin = 0x33FF80, length = 0x000076 /* Part of FLASHA. Program with all 0x0000 when CSM is in use. */
BEGIN : origin = 0x33FFF6, length = 0x000002 /* Part of FLASHA. Used for "boot to Flash" bootloader mode. */
CSM_PWL : origin = 0x33FFF8, length = 0x000008 /* Part of FLASHA. CSM password locations in FLASHA */
OTP : origin = 0x380400, length = 0x000400 /* on-chip OTP */
ADC_CAL : origin = 0x380080, length = 0x000009 /* ADC_cal function in Reserved memory */
IQTABLES : origin = 0x3FE000, length = 0x000b50 /* IQ Math Tables in Boot ROM */
IQTABLES2 : origin = 0x3FEB50, length = 0x00008c /* IQ Math Tables in Boot ROM */
FPUTABLES : origin = 0x3FEBDC, length = 0x0006A0 /* FPU Tables in Boot ROM */
ROM : origin = 0x3FF27C, length = 0x000D44 /* Boot ROM */
RESET : origin = 0x3FFFC0, length = 0x000002 /* part of boot ROM */
VECTORS : origin = 0x3FFFC2, length = 0x00003E /* part of boot ROM */
PAGE 1 : /* Data Memory */
/* Memory (RAM/FLASH/OTP) blocks can be moved to PAGE0 for program allocation */
/* Registers remain on PAGE1 */
BOOT_RSVD : origin = 0x000000, length = 0x000050 /* Part of M0, BOOT rom will use this for stack */
RAMM0 : origin = 0x000050, length = 0x0003B0 /* on-chip RAM block M0 */
RAMM1 : origin = 0x000400, length = 0x000400 /* on-chip RAM block M1 */
RAML4 : origin = 0x00C000, length = 0x003000 /* on-chip RAM block L1 */
RAML5 : origin = 0x00F000, length = 0x001000 /* on-chip RAM block L1 */
ZONE6B : origin = 0x100000, length = 0x100000 /* XINTF zone 6 - data space */
ZONE7B : origin = 0x20FC00, length = 0x000400 /* XINTF zone 7 - data space */
FLASHB : origin = 0x330000, length = 0x008000 /* on-chip FLASH */
}
/* Allocate sections to memory blocks.
Note:
codestart user defined section in DSP28_CodeStartBranch.asm used to redirect code
execution when booting to flash
ramfuncs user defined section to store functions that will be copied from Flash into RAM
*/
SECTIONS
{
/* Allocate program areas: */
.cinit : LOAD=FLASHA,
RUN = RAML112,
LOAD_START(_cinit_loadstart),
RUN_START(_cinit_runstart),
SIZE(_cinit_size)
PAGE = 0
.pinit : > FLASHA, PAGE = 0
codestart : > BEGIN PAGE = 0
wddisable : > FLASHA PAGE = 0
copysections : > FLASHA PAGE = 0
.text : LOAD = FLASHC,
RUN = RAML112,
LOAD_START(_text_loadstart),
RUN_START(_text_runstart),
SIZE(_text_size)
PAGE = 0
csmpasswds : > CSM_PWL PAGE = 0
csm_rsvd : > CSM_RSVD PAGE = 0
/* Allocate uninitalized data sections: */
.stack : > RAMM1 PAGE = 1
.ebss : > RAML4 PAGE = 1
.esysmem : > RAMM1 PAGE = 1
/* Initalized sections go in Flash */
/* For SDFlash to program these, they must be allocated to page 0 */
.econst : > FLASHA PAGE = 0
.switch : > FLASHA PAGE = 0
/* Allocate IQ math areas: */
IQmath : > FLASHC PAGE = 0 /* Math Code */
IQmathTables : > IQTABLES, PAGE = 0, TYPE = NOLOAD
/* Uncomment the section below if calling the IQNexp() or IQexp()
functions from the IQMath.lib library in order to utilize the
relevant IQ Math table in Boot ROM (This saves space and Boot ROM
is 1 wait-state). If this section is not uncommented, IQmathTables2
will be loaded into other memory (SARAM, Flash, etc.) and will take
up space, but 0 wait-state is possible.
*/
/*
IQmathTables2 : > IQTABLES2, PAGE = 0, TYPE = NOLOAD
{
IQmath.lib<IQNexpTable.obj> (IQmathTablesRam)
}
*/
FPUmathTables : > FPUTABLES, PAGE = 0, TYPE = NOLOAD
/* Allocate DMA-accessible RAM sections: */
DMARAML4 : > RAML4, PAGE = 1
DMARAML5 : > RAML5, PAGE = 1
/*DMARAML6 : > RAML6, PAGE = 1
DMARAML7 : > RAML7, PAGE = 1*/
/* Allocate 0x400 of XINTF Zone 7 to storing data */
ZONE6DATA : > ZONE6B, PAGE = 1
ZONE7DATA : > ZONE7B, PAGE = 1
/* .reset is a standard section used by the compiler. It contains the */
/* the address of the start of _c_int00 for C Code. /*
/* When using the boot ROM this section and the CPU vector */
/* table is not needed. Thus the default type is set here to */
/* DSECT */
.reset : > RESET, PAGE = 0, TYPE = DSECT
vectors : > VECTORS PAGE = 0, TYPE = DSECT
/* Allocate ADC_cal function (pre-programmed by factory into TI reserved memory) */
.adc_cal : load = ADC_CAL, PAGE = 0, TYPE = NOLOAD
}
/*
//===========================================================================
// End of file.
//===========================================================================
*/
