|  | /* | 
|  | * The ARM LDRD and Thumb LDRSB instructions use bit 20/11 (ARM/Thumb) | 
|  | * differently than every other instruction, so it is set to 0 (write) | 
|  | * even though the instructions are read instructions. This means that | 
|  | * during an abort the instructions will be treated as a write and the | 
|  | * handler will raise a signal from unwriteable locations if they | 
|  | * fault. We have to specifically check for these instructions | 
|  | * from the abort handlers to treat them properly. | 
|  | * | 
|  | */ | 
|  |  | 
|  | .macro	do_thumb_abort | 
|  | tst	r3, #PSR_T_BIT | 
|  | beq	not_thumb | 
|  | ldrh	r3, [r2]			@ Read aborted Thumb instruction | 
|  | and	r3, r3, # 0xfe00		@ Mask opcode field | 
|  | cmp	r3, # 0x5600			@ Is it ldrsb? | 
|  | orreq	r3, r3, #1 << 11		@ Set L-bit if yes | 
|  | tst	r3, #1 << 11			@ L = 0 -> write | 
|  | orreq	r1, r1, #1 << 11		@ yes. | 
|  | mov	pc, lr | 
|  | not_thumb: | 
|  | .endm | 
|  |  | 
|  | /* | 
|  | * We check for the following insturction encoding for LDRD. | 
|  | * | 
|  | * [27:25] == 0 | 
|  | *   [7:4] == 1101 | 
|  | *    [20] == 0 | 
|  | */ | 
|  | .macro	do_ldrd_abort | 
|  | tst	r3, #0x0e000000			@ [27:25] == 0 | 
|  | bne	not_ldrd | 
|  | and	r2, r3, #0x000000f0		@ [7:4] == 1101 | 
|  | cmp	r2, #0x000000d0 | 
|  | bne	not_ldrd | 
|  | tst	r3, #1 << 20			@ [20] == 0 | 
|  | moveq	pc, lr | 
|  | not_ldrd: | 
|  | .endm | 
|  |  |