patch-2.1.80 linux/arch/arm/lib/backtrace.S

• Lines: 101
• Date: Tue Jan 20 16:39:41 1998
• Orig file: v2.1.79/linux/arch/arm/lib/backtrace.S
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.79/linux/arch/arm/lib/backtrace.S linux/arch/arm/lib/backtrace.S
@@ -0,0 +1,100 @@
+/*
+ * linux/arch/arm/lib/backtrace.S
+ *
+ * Copyright (C) 1995, 1996 Russell King
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+		.text
+
+@ fp is 0 or stack frame
+
+#define frame	r4
+#define next	r5
+#define save	r6
+#define mask	r7
+#define offset	r8
+
+ENTRY(__backtrace)
+		mov	r1, #0x10
+		mov	r0, fp
+
+ENTRY(c_backtrace)
+		stmfd	sp!, {r4 - r8, lr}	@ Save an extra register so we have a location...
+		tst	r1, #0x10		@ 26 or 32-bit?
+		moveq	mask, #0xfc000003
+		movne	mask, #0
+		tst	mask, r0
+		movne	r0, #0
+		movs	frame, r0
+1:		moveq	r0, #-2
+		LOADREGS(eqfd, sp!, {r4 - r8, pc})
+
+2:		stmfd	sp!, {pc}			@ calculate offset of PC in STMIA instruction
+		ldr	r0, [sp], #4
+		adr	r1, 2b - 4
+		sub	offset, r0, r1
+
+3:		tst	frame, mask			@ Check for address exceptions...
+		bne	1b
+
+		ldmda	frame, {r0, r1, r2, r3}		@ fp, sp, lr, pc
+		mov	next, r0
+
+		sub	save, r3, offset		@ Correct PC for prefetching
+		bic	save, save, mask
+		adr	r0, .Lfe
+		mov	r1, save
+		bic	r2, r2, mask
+		bl	SYMBOL_NAME(printk)
+
+		sub	r0, frame, #16
+		ldr	r1, [save, #4]
+		mov	r3, r1, lsr #10
+		ldr	r2, .Ldsi+4
+		teq	r3, r2			@ Check for stmia sp!, {args}
+		addeq	save, save, #4		@ next instruction
+		bleq	.Ldumpstm
+
+		ldr	r1, [save, #4]		@ Get 'stmia sp!, {rlist, fp, ip, lr, pc}' instruction
+		mov	r3, r1, lsr #10
+		ldr	r2, .Ldsi
+		teq	r3, r2
+		bleq	.Ldumpstm
+
+		teq	frame, next
+		movne	frame, next
+		teqne	frame, #0
+		bne	3b
+		LOADREGS(fd, sp!, {r4 - r8, pc})
+
+
+#define instr r4
+#define reg   r5
+#define stack r6
+
+.Ldumpstm:	stmfd	sp!, {instr, reg, stack, lr}
+		mov	stack, r0
+		mov	instr, r1
+		mov	reg, #9
+
+1:		mov	r3, #1
+		tst	instr, r3, lsl reg
+		beq	2f
+		ldr	r2, [stack], #-4
+		mov	r1, reg
+		adr	r0, .Lfp
+		bl	SYMBOL_NAME(printk)
+2:		subs	reg, reg, #1
+		bpl	1b
+
+		mov	r0, stack
+		LOADREGS(fd, sp!, {instr, reg, stack, pc})
+
+.Lfe:		.ascii	"Function entered at [<%p>] from [<%p>]\n"
+		.byte 0
+.Lfp:		.ascii	"  r%d = %p\n"
+		.byte 0
+		.align
+.Ldsi:		.word	0x00e92dd8 >> 2
+		.word	0x00e92d00 >> 2