[openrisc] Problem with jump behavior

["Damon Brantley" <brantley@mcloudteleco.com>]

I am getting started with experimenting with openrisc. I pulled down and
built the 
binutils and gcc for use with cygwin. I am using the ModelSim simulator
that comes 
with the Xilinx WebPack.

While experimenting with some very simple  c programs, it looks like my
jumps are off
by one instruction.

A test program I have been working with is:
void main(){
	int i=0;
	while(1){
		i=i+1;
	}
}

The disassembly is 

00010000 <_start>:
   10000:       18 20 00 00     l.movhi r1,0x0
   10004:       a8 21 00 10     l.ori r1,r1,0x10
   10008:       00 00 00 04     l.j 10018 <_main>
   1000c:       15 00 00 00     l.nop 0x0
   10010:       15 00 00 00     l.nop 0x0
   10014:       03 ff ff fb     l.j 10000 <_start>

00010018 <_main>:
   10018:       9c 21 ff f8     l.addi r1,r1,0xfffffff8
   1001c:       d4 01 10 00     l.sw 0x0(r1),r2
   10020:       9c 41 00 08     l.addi r2,r1,0x8
   10024:       9c 60 00 00     l.addi r3,r0,0x0
   10028:       d7 e2 1f fc     l.sw 0xfffffffc(r2),r3
   1002c:       84 62 ff fc     l.lwz r3,0xfffffffc(r2)
   10030:       9c 63 00 01     l.addi r3,r3,0x1
   10034:       d7 e2 1f fc     l.sw 0xfffffffc(r2),r3
   10038:       03 ff ff fd     l.j 1002c <_main+0x14>
   1003c:       15 00 00 00     l.nop 0x0
   10040:       84 41 00 00     l.lwz r2,0x0(r1)
   10044:       44 00 48 00     l.jr r9
   10048:       9c 21 00 08     l.addi r1,r1,0x8


What I am seeing in the simulator is when a the jump at 10008 is executed,
instead of seeing iwb_adr_o going to 
10018, I am seeing it go to 1001c. 

In this case the program simulates as expected, but when I add function
calls the test programs fail because 
the first instruction is missed, which is usually setting up a stack frame.

This is what I am using for building my test program:

/opt/or32-uclinux/bin/or32-uclinux-gcc  -g -Wa,-a=crt0.asm  -c -o crt0.or32
crt0.S
/opt/or32-uclinux/bin/or32-uclinux-gcc  -g -Wa,-a=test1.asm  -c -o
test1.or32 test1.c
/opt/or32-uclinux/bin/or32-uclinux-ld  -Ttext 10000 -Tdata 20 -o test1.bin
crt0.or32 test1.or32 

Am I missing a compile or link flag or is model sim possibly doing the
simulation wrong.

Thanks,
Damon

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