diff --git a/asm_unpackers/Makefile b/asm_unpackers/Makefile index 46c86f1..90b465f 100644 --- a/asm_unpackers/Makefile +++ b/asm_unpackers/Makefile @@ -39,6 +39,19 @@ build/unpack_armv6m.bin: unpack_armv6m.S arm-none-eabi-gcc -march=armv6-m -c -o build/unpack_armv6m.o $? arm-none-eabi-objcopy -O binary --only-section=.text build/unpack_armv6m.o $@ +build/unpack_arm32: ../c_unpacker/main.c unpack_arm32.S + mkdir -p build + arm-linux-gnueabihf-gcc -g -static -o $@ $^ + +test_arm32: build/unpack_arm32 + qemu-arm $< test_data.upk /tmp/out.bin + cmp test_data.bin /tmp/out.bin + +build/unpack_arm32.bin: unpack_arm32.S + mkdir -p build + arm-none-eabi-gcc -c -o build/unpack_arm32.o $? + arm-none-eabi-objcopy -O binary --only-section=.text build/unpack_arm32.o $@ + build/unpack_c: ../c_unpacker/main.c ../c_unpacker/unpack.c mkdir -p build gcc -g -o $@ $^ @@ -47,5 +60,5 @@ test_c: build/unpack_c $< test_data.upk /tmp/out.bin cmp test_data.bin /tmp/out.bin -sizes: build/unpack_armv6m.bin build/unpack_riscv64.bin build/unpack_riscv32.bin +sizes: build/unpack_armv6m.bin build/unpack_riscv64.bin build/unpack_riscv32.bin build/unpack_arm32.bin ls -l build/*.bin \ No newline at end of file diff --git a/asm_unpackers/unpack_arm32.S b/asm_unpackers/unpack_arm32.S new file mode 100644 index 0000000..99b880b --- /dev/null +++ b/asm_unpackers/unpack_arm32.S @@ -0,0 +1,106 @@ +.arm + +.section .text + +.global upkr_unpack +.type upkr_unpack, %function +// r0 .. out_ptr (returned) +// r1 .. in_ptr (returned) +// r2 .. state +// r3 .. offset +// r4 .. prev_was_literal / decode_length ret +// r5 .. context index +// r6 .. decode_length temp +// r7 .. probs ptr +// r8-r11 .. decode_bit temp +// r12 .. decode_length return address +upkr_unpack: + push { r3-r11, lr } + + mov r2, #384 + movs r3, #128 +.Lclear: + subs r2, r2, #1 + strb r3, [sp, -r2] + bne .Lclear + +.Lloop: + movs r5, #0 + bl upkr_decode_bit + bcc .Ldata +.Lmatch: + mov r5, #256 + cmp r4, #0 + beq 1f + + bl upkr_decode_bit + bcc 2f + +1: + bl upkr_decode_length + subs r3, r4, #1 + popeq { r3-r11, pc } +2: + + mov r5, #256+64 + bl upkr_decode_length +.Lcopy_loop: + ldrb r5, [r0, -r3] +.Lstore: + strb r5, [r0], #1 + subs r4, r4, #1 + bgt .Lcopy_loop + b .Lloop + +.Ldata: + movs r5, #1 + +.Ldata_loop: + bl upkr_decode_bit + adcs r5, r5, r5 + rsbs r4, r5, #256 + bgt .Ldata_loop + b .Lstore + +.type upkr_decode_length, %function +upkr_decode_length: + mov r12, lr + + movs r6, #0 + mov r4, #1 +.Lbit_loop: + adds r5, r5, #1 + bl upkr_decode_bit + addcc r4, r4, r6 + movcc pc, r12 + + adds r5, r5, #1 + bl upkr_decode_bit + addcs r6, r6, r4 + lsls r4, r4, #1 + b .Lbit_loop + +.type upkr_decode_bit, %function +upkr_fill_state: + ldrb r8, [r1], #1 + orr r2, r8, r2, lsl #8 + +upkr_decode_bit: + cmp r2, #4096 + blt upkr_fill_state + + ldrb r8, [sp, -r5] + and r9, r2, #255 + add r9, r9, #1 + cmp r8, r9 + rsbcs r8, r8, #256 + mov r9, r2, lsr#8 + addcc r9, r9, #1 + mul r9, r8, r9 + sub r2, r2, r9 + add r9, r8, #8 + sub r8, r8, r9, lsr#4 + rsbcs r8, r8, #256 + strb r8, [sp, -r5] + mov pc, r14 + diff --git a/asm_unpackers/unpack_riscv.S b/asm_unpackers/unpack_riscv.S index 86040b8..c3f101c 100644 --- a/asm_unpackers/unpack_riscv.S +++ b/asm_unpackers/unpack_riscv.S @@ -83,7 +83,7 @@ upkr_decode_bit: addi x14, x14, 1 sub t2, sp, x14 - lbu x12, 0(t2) + lbu x12, (t2) andi x8, x13, 255 sltu x15, x8, x12 @@ -104,7 +104,7 @@ upkr_decode_bit: sub x12, x0, x12 1: - sb x12, 0(t2) + sb x12, (t2) jalr ra