[llvm-dev] llvm-bjdump and ELF-ARM/Thumb

[Johan Wehrli via llvm-dev]

Hi Everyone,

When I used llvm-objdump to disassemble an ELF armv7 or thumb I have this error message:

llvm-objdump: warning: invalid instruction encoding

This message appears directly into the output and the output is mostly wrong (the invalid instruction create a shift in the addresses) :


    1a6d:	ff 2f e1 08 	stmeq	r1!, {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, sp} ^
    1a71:	30 90 e5 00 	rsceq	r9, r5, r0, lsr r0
    1a75:	10 a0 e1 00 	rsceq	r10, r1, r0, lsl r0
    1a79:	00 53 e3 1e 	cdpne	p3, #14, c5, c3, c0, #0
llvm-objdump: warning: invalid instruction encoding
    1a7e:	2f 01 01 00 	andeq	r0, r1, pc, lsr #2
llvm-objdump: warning: invalid instruction encoding
    1a83:	e3 13 ff 2f 	svchs	#16716771
llvm-objdump: warning: invalid instruction encoding

The binaries I try to read are c++ dynamic libraries for Android.

I have used the following parameters:

-llvm-objcdump mylib.so -d -arch=arm
-llvm-objcdump mylib.so -d -arch=armv7
-llvm-objcdump mylib.so -d -arch=thumb

or with the following triples:

armv7-none-linux-android
thumbv7-none-linux-android

Does anyone know why I have this error? Am I missing some input parameters?

This is strange because it works great on iOS binaries (both thumb or arm).

Greetings,

Johan