Can't Assemble Disassembled ARM-ELF instructions LDREQD, STREQD

[Andrew "ZACK" Zacharias]

I'm using arm-elf-objdump to disassemble a shared library. My hope is to 
reassemble to an object file. (Source code for the library is unavailable)

The disassembled output contains multiple variations of:
ldreqd ip, [r2], -r8
streqd  r0, [r0], -r6
I think these are pseudo-instructions.
I've tried various options with objdump but all produce similar results.

My target is a Cirrus Logic EP7312 processor.

I assemble using arm-elf-as with the following options:
 -marm7tdmi -marmv4t -mall

arm-elf-as does not recognize the opcodes.
Any idea what I'm doing wrong?
Thanks!
 Zack