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[PATCH 10/26] arm: Introduce and use LDST_PCREL


Macro-ising the few instances where we need to distinguish between
arm and thumb pc-relative memory operations.
---
	* sysdeps/arm/sysdep.h (LDST_PCREL): New macro.
	* sysdeps/unix/arm/sysdep.S (__syscall_error): Use LDST_PCREL.
	Fix up gottpoff load of errno for thumb2.
	* sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h
	(SINGLE_THREAD_P): Use LDST_PCREL.
	(PSEUDO_PROLOGUE): Remove.
	(PSEUDO): Don't use it.
	* sysdeps/unix/sysv/linux/arm/sysdep.h (SYSCALL_ERROR_HANDLER):
	Use LDST_PCREL.
---
 ports/sysdeps/arm/sysdep.h                         | 18 +++++++++++++
 ports/sysdeps/unix/arm/sysdep.S                    | 30 +++++++++++-----------
 .../unix/sysv/linux/arm/nptl/sysdep-cancel.h       | 10 ++------
 ports/sysdeps/unix/sysv/linux/arm/sysdep.h         | 10 +++-----
 4 files changed, 39 insertions(+), 29 deletions(-)

diff --git a/ports/sysdeps/arm/sysdep.h b/ports/sysdeps/arm/sysdep.h
index 4a9f05a..b7ba9b1 100644
--- a/ports/sysdeps/arm/sysdep.h
+++ b/ports/sysdeps/arm/sysdep.h
@@ -129,4 +129,22 @@
 # define pc_ofs		8
 #endif
 
+/* Load or store to/from a pc-relative EXPR into/from R, using T.  */
+#ifdef __thumb2__
+# define LDST_PCREL(OP, R, T, EXPR) \
+	ldr	T, 98f;					\
+	.subsection 2;					\
+98:	.word	EXPR - 99f - pc_ofs;			\
+	.previous;					\
+99:	add	T, T, pc;				\
+	OP	R, [T]
+#else
+# define LDST_PCREL(OP, R, T, EXPR) \
+	ldr	T, 98f;					\
+	.subsection 2;					\
+98:	.word	EXPR - 99f - pc_ofs;			\
+	.previous;					\
+99:	OP	R, [pc, T]
+#endif
+
 #endif	/* __ASSEMBLER__ */
diff --git a/ports/sysdeps/unix/arm/sysdep.S b/ports/sysdeps/unix/arm/sysdep.S
index 951642f..969628a 100644
--- a/ports/sysdeps/unix/arm/sysdep.S
+++ b/ports/sysdeps/unix/arm/sysdep.S
@@ -37,26 +37,26 @@ __syscall_error:
 #endif
 
 #ifndef IS_IN_rtld
-	mov ip, lr
+	mov	ip, lr
 	cfi_register (lr, ip)
-	mov r1, r0
-
+	mov	r1, r0
 	GET_TLS
+	ldr	r2, 1f
+#ifdef __thumb__
+2:	add	r2, r2, pc
+	ldr	r2, [r2]
+#else
+2:	ldr	r2, [pc, r2]
+#endif
+	str	r1, [r0, r2]
+	mvn	r0, #0
+	DO_RET(ip)
 
-	ldr r2, 1f
-2:	ldr r2, [pc, r2]
-	str r1, [r0, r2]
-	mvn r0, #0
-	RETINSTR (, ip)
-
-1:	.word errno(gottpoff) + (. - 2b - pc_ofs)
+1:	.word	errno(gottpoff) + (. - 2b - pc_ofs)
 #elif RTLD_PRIVATE_ERRNO
-	ldr r1, 1f
-0:	str r0, [pc, r1]
-	mvn r0, $0
+	LDST_PCREL(str, r0, r1, C_SYMBOL_NAME(rtld_errno))
+	mvn	r0, #0
 	DO_RET(r14)
-
-1:	.word C_SYMBOL_NAME(rtld_errno) - 0b - pc_ofs
 #else
 #error "Unsupported non-TLS case"
 #endif
diff --git a/ports/sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h b/ports/sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h
index 1745f9e..b6dc3e0 100644
--- a/ports/sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h
+++ b/ports/sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h
@@ -31,7 +31,6 @@
 # undef PSEUDO
 # define PSEUDO(name, syscall_name, args)				\
   .section ".text";							\
-    PSEUDO_PROLOGUE;							\
   .type __##syscall_name##_nocancel,%function;				\
   .globl __##syscall_name##_nocancel;					\
   __##syscall_name##_nocancel:						\
@@ -207,12 +206,8 @@ extern int __local_multiple_threads attribute_hidden;
 #   define SINGLE_THREAD_P __builtin_expect (__local_multiple_threads == 0, 1)
 #  else
 #   define SINGLE_THREAD_P						\
-  ldr ip, 1b;								\
-2:									\
-  ldr ip, [pc, ip];							\
-  teq ip, #0;
-#   define PSEUDO_PROLOGUE						\
-  1:  .word __local_multiple_threads - 2f - pc_ofs;
+	LDST_PCREL(ldr, ip, ip, __local_multiple_threads);		\
+	teq ip, #0
 #  endif
 # else
 /*  There is no __local_multiple_threads for librt, so use the TCB.  */
@@ -221,7 +216,6 @@ extern int __local_multiple_threads attribute_hidden;
   __builtin_expect (THREAD_GETMEM (THREAD_SELF,				\
 				   header.multiple_threads) == 0, 1)
 #  else
-#   define PSEUDO_PROLOGUE
 #   define SINGLE_THREAD_P						\
   stmfd	sp!, {r0, lr};							\
   cfi_adjust_cfa_offset (8);						\
diff --git a/ports/sysdeps/unix/sysv/linux/arm/sysdep.h b/ports/sysdeps/unix/sysv/linux/arm/sysdep.h
index c1f2c9e..e448e61 100644
--- a/ports/sysdeps/unix/sysv/linux/arm/sysdep.h
+++ b/ports/sysdeps/unix/sysv/linux/arm/sysdep.h
@@ -125,12 +125,10 @@
 # if RTLD_PRIVATE_ERRNO
 #  define SYSCALL_ERROR_HANDLER					\
 __local_syscall_error:						\
-       ldr     r1, 1f;						\
-       rsb     r0, r0, #0;					\
-0:     str     r0, [pc, r1];					\
-       mvn     r0, #0;						\
-       DO_RET(lr);						\
-1:     .word C_SYMBOL_NAME(rtld_errno) - 0b - pc_ofs;
+	rsb	r0, r0, #0;					\
+	LDST_PCREL(str, r0, r1, C_SYMBOL_NAME(rtld_errno));	\
+	mvn	r0, #0;						\
+	DO_RET(lr)
 # else
 #  if defined(__ARM_ARCH_4T__) && defined(__THUMB_INTERWORK__)
 #   define POP_PC \
-- 
1.8.1.2


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