[AArch64] Add more cfi annotations to tlsdesc entry points

Backtrace through _dl_tlsdesc_resolve_rela was broken because the offset
of x30 from cfa was not in the debug info.

Add enough annotation so backtracing from the dynamic linker through
tlsdesc entry points works and the debugger shows registers correctly.

2 files changed, 76 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 3c9d6ba461..22889ee2e8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,12 @@
 
 2017-06-21  Szabolcs Nagy  <szabolcs.nagy@arm.com>
 
+	* sysdeps/aarch64/dl-tlsdesc.S (_dl_tlsdesc_dynamic): Add cfi
+	annotation.
+	(_dl_tlsdesc_resolve_rela, _dl_tlsdesc_resolve_hold): Likewise.
+
+2017-06-21  Szabolcs Nagy  <szabolcs.nagy@arm.com>
+
 	* sysdeps/aarch64/dl-machine.h (RTLD_START_1): Change _dl_argv to the
 	hidden __GI__dl_argv symbol.
 
diff --git a/sysdeps/aarch64/dl-tlsdesc.S b/sysdeps/aarch64/dl-tlsdesc.S
index 94679a04ca..a70cfd513c 100644
--- a/sysdeps/aarch64/dl-tlsdesc.S
+++ b/sysdeps/aarch64/dl-tlsdesc.S
@@ -176,6 +176,8 @@ _dl_tlsdesc_dynamic:
 # define NSAVEXREGPAIRS 2
 	stp	x29, x30, [sp,#-(32+16*NSAVEXREGPAIRS)]!
 	cfi_adjust_cfa_offset (32+16*NSAVEXREGPAIRS)
+	cfi_rel_offset (x29, 0)
+	cfi_rel_offset (x30, 8)
 	mov	x29, sp
 	DELOUSE (0)
 
@@ -184,6 +186,10 @@ _dl_tlsdesc_dynamic:
 
 	stp	x1,  x2, [sp, #32+16*0]
 	stp	x3,  x4, [sp, #32+16*1]
+	cfi_rel_offset (x1, 32)
+	cfi_rel_offset (x2, 32+8)
+	cfi_rel_offset (x3, 32+16)
+	cfi_rel_offset (x4, 32+24)
 
 	mrs	x4, tpidr_el0
 	/* The ldar here happens after the load from [x0] at the call site
@@ -213,6 +219,8 @@ _dl_tlsdesc_dynamic:
 
 	ldp	x29, x30, [sp], #(32+16*NSAVEXREGPAIRS)
 	cfi_adjust_cfa_offset (-32-16*NSAVEXREGPAIRS)
+	cfi_restore (x29)
+	cfi_restore (x30)
 # undef NSAVEXREGPAIRS
 	RET
 2:
@@ -230,6 +238,20 @@ _dl_tlsdesc_dynamic:
 	stp	x13, x14, [sp, #16*4]
 	stp	x15, x16, [sp, #16*5]
 	stp	x17, x18, [sp, #16*6]
+	cfi_rel_offset (x5, 0)
+	cfi_rel_offset (x6, 8)
+	cfi_rel_offset (x7, 16)
+	cfi_rel_offset (x8, 16+8)
+	cfi_rel_offset (x9, 16*2)
+	cfi_rel_offset (x10, 16*2+8)
+	cfi_rel_offset (x11, 16*3)
+	cfi_rel_offset (x12, 16*3+8)
+	cfi_rel_offset (x13, 16*4)
+	cfi_rel_offset (x14, 16*4+8)
+	cfi_rel_offset (x15, 16*5)
+	cfi_rel_offset (x16, 16*5+8)
+	cfi_rel_offset (x17, 16*6)
+	cfi_rel_offset (x18, 16*6+8)
 
 	SAVE_Q_REGISTERS
 
@@ -268,8 +290,14 @@ _dl_tlsdesc_dynamic:
 	.align 2
 _dl_tlsdesc_resolve_rela:
 #define	NSAVEXREGPAIRS 9
+	/* The tlsdesc PLT entry pushes x2 and x3 to the stack.  */
+	cfi_adjust_cfa_offset (16)
+	cfi_rel_offset (x2, 0)
+	cfi_rel_offset (x3, 8)
 	stp	x29, x30, [sp, #-(32+16*NSAVEXREGPAIRS)]!
 	cfi_adjust_cfa_offset (32+16*NSAVEXREGPAIRS)
+	cfi_rel_offset (x29, 0)
+	cfi_rel_offset (x30, 8)
 	mov	x29, sp
 	stp	 x1,  x4, [sp, #32+16*0]
 	stp	 x5,  x6, [sp, #32+16*1]
@@ -280,6 +308,23 @@ _dl_tlsdesc_resolve_rela:
 	stp	x15, x16, [sp, #32+16*6]
 	stp	x17, x18, [sp, #32+16*7]
 	str	x0,       [sp, #32+16*8]
+	cfi_rel_offset (x1, 32)
+	cfi_rel_offset (x4, 32+8)
+	cfi_rel_offset (x5, 32+16)
+	cfi_rel_offset (x6, 32+16+8)
+	cfi_rel_offset (x7, 32+16*2)
+	cfi_rel_offset (x8, 32+16*2+8)
+	cfi_rel_offset (x9, 32+16*3)
+	cfi_rel_offset (x10, 32+16*3+8)
+	cfi_rel_offset (x11, 32+16*4)
+	cfi_rel_offset (x12, 32+16*4+8)
+	cfi_rel_offset (x13, 32+16*5)
+	cfi_rel_offset (x14, 32+16*5+8)
+	cfi_rel_offset (x15, 32+16*6)
+	cfi_rel_offset (x16, 32+16*6+8)
+	cfi_rel_offset (x17, 32+16*7)
+	cfi_rel_offset (x18, 32+16*7+8)
+	cfi_rel_offset (x0, 32+16*8)
 
 	SAVE_Q_REGISTERS
 
@@ -304,6 +349,8 @@ _dl_tlsdesc_resolve_rela:
 	ldp	x17, x18, [sp, #32+16*7]
 	ldp	x29, x30, [sp], #(32+16*NSAVEXREGPAIRS)
 	cfi_adjust_cfa_offset (-32-16*NSAVEXREGPAIRS)
+	cfi_restore (x29)
+	cfi_restore (x30)
 	ldp	x2, x3, [sp], #16
 	cfi_adjust_cfa_offset (-16)
 	RET
@@ -332,6 +379,8 @@ _dl_tlsdesc_resolve_hold:
 1:
 	stp	x29, x30, [sp, #-(32+16*NSAVEXREGPAIRS)]!
 	cfi_adjust_cfa_offset (32+16*NSAVEXREGPAIRS)
+	cfi_rel_offset (x29, 0)
+	cfi_rel_offset (x30, 8)
 	mov	x29, sp
 	stp	 x1,  x2, [sp, #32+16*0]
 	stp	 x3,  x4, [sp, #32+16*1]
@@ -343,6 +392,25 @@ _dl_tlsdesc_resolve_hold:
 	stp	x15, x16, [sp, #32+16*7]
 	stp	x17, x18, [sp, #32+16*8]
 	str	x0,       [sp, #32+16*9]
+	cfi_rel_offset (x1, 32)
+	cfi_rel_offset (x2, 32+8)
+	cfi_rel_offset (x3, 32+16)
+	cfi_rel_offset (x4, 32+16+8)
+	cfi_rel_offset (x5, 32+16*2)
+	cfi_rel_offset (x6, 32+16*2+8)
+	cfi_rel_offset (x7, 32+16*3)
+	cfi_rel_offset (x8, 32+16*3+8)
+	cfi_rel_offset (x9, 32+16*4)
+	cfi_rel_offset (x10, 32+16*4+8)
+	cfi_rel_offset (x11, 32+16*5)
+	cfi_rel_offset (x12, 32+16*5+8)
+	cfi_rel_offset (x13, 32+16*6)
+	cfi_rel_offset (x14, 32+16*6+8)
+	cfi_rel_offset (x15, 32+16*7)
+	cfi_rel_offset (x16, 32+16*7+8)
+	cfi_rel_offset (x17, 32+16*8)
+	cfi_rel_offset (x18, 32+16*8+8)
+	cfi_rel_offset (x0, 32+16*9)
 
 	SAVE_Q_REGISTERS
 
@@ -367,6 +435,8 @@ _dl_tlsdesc_resolve_hold:
 	ldp	x17, x18, [sp, #32+16*8]
 	ldp	x29, x30, [sp], #(32+16*NSAVEXREGPAIRS)
 	cfi_adjust_cfa_offset (-32-16*NSAVEXREGPAIRS)
+	cfi_restore (x29)
+	cfi_restore (x30)
 	RET
 	cfi_endproc
 	.size	_dl_tlsdesc_resolve_hold, .-_dl_tlsdesc_resolve_hold