Compiler

I just tried assembling the following code:

        .set noat
        movia at,((90000000+57600)/115200)

with the command line:

nios2-elf-gcc -c -o test.o test.s
nios2-elf-objdump -S test.o

And got a pair of instructions which load up the value 781 (decimal).

Which version of the tools are you using?

Test code as following:# ====================================

.set noat

_start:

movia at,((90000000+57600)/115200)

movia at,((90057600)/115200)

.end# ====================================

I got these result:

[NIOS2 GNU Shell]$ nios2-elf-gcc -c -o test.o test.S

[NIOS2 GNU Shell]$ nios2-elf-objdump -S test.o

test.o: file format elf32-littlenios2

Disassembly of section .text:

00000000 <_start>:

0: 00415774 movhi at,1373

4: 0852a014 ori at,at,19072

8: 00400034 movhi at,0

c: 0840c354 ori at,at,781

[NIOS2 GNU Shell]$

Why?

but , got the result with these cmd line:

[NIOS2 GNU Shell]$ nios2-elf-as -o test.o test.S

[NIOS2 GNU Shell]$ nios2-elf-objdump -S test.o

test.o: file format elf32-littlenios2

Disassembly of section .text:

00000000 <_start>:

0: 00400034 movhi at,0

4: 0840c344 addi at,at,781

8: 00400034 movhi at,0

c: 0840c344 addi at,at,781

/cygdrive/g/nios2/src/boot_loader

[NIOS2 GNU Shell]$

--- Quote Start ---

originally posted by simon.embed@Mar 16 2005, 10:01 AM

test code as following:# ====================================

.set noat

_start:

movia at,((90000000+57600)/115200)

movia at,((90057600)/115200)

.end# ====================================

i got these result:

[nios2 gnu shell]$ nios2-elf-gcc -c -o test.o test.s

[nios2 gnu shell]$ nios2-elf-objdump -s test.o

test.o: file format elf32-littlenios2

disassembly of section .text:

00000000 <_start>:

0: 00415774 movhi at,1373

4: 0852a014 ori at,at,19072

8: 00400034 movhi at,0

c: 0840c354 ori at,at,781

[nios2 gnu shell]$

why?

--- Quote End ---

What version are you running? If you type nios2-elf-gcc -v this will tell you.

Using your file

.set noat

_start:

movia at,((90000000+57600)/115200)

movia at,((90057600)/115200)

.end

With the command lines below I get exactly what you&#39;d expect

[SOPC Builder]$ nios2-elf-gcc -c -o test.o test.S

/cygdrive/d

[SOPC Builder]$ nios2-elf-objdump -S test.o

test.o: file format elf32-littlenios2

Disassembly of section .text:

00000000 <_start>:

0: 00400034 movhi at,0

4: 0840c344 addi at,at,781

8: 00400034 movhi at,0

c: 0840c344 addi at,at,781

maybe the compiler bug for the following test code:# test.S# define ALT_CPU_FREQ 90000000# define BAUD_RATE 2400 //1200# define C_DIVISOR ((ALT_CPU_FREQ+BAUD_RATE/2)/BAUD_RATE)

.equ A_DIVISOR , ((ALT_CPU_FREQ+BAUD_RATE/2)/BAUD_RATE)

.macro MOVUIK32 _reg,_val

.if (\_val >>16) == 0

MOVUI \_reg,%lo(\_val)

.elseif (\_val <<16) == 0

MOVHI \_reg,%hi(\_val)

.else

MOVIA \_reg,\_val

.endif

.endm

.section .text

.align 2

.set noat

_start:

MOVUIK32 r2,C_DIVISOR

MOVUIK32 r3,A_DIVISOR

.end

You may change the valu of ALT_CPU_FREQ and BAUD_RATE macros, and then check the compiling result!