From: Richard Miller <miller.research@gmail.com>
Date: Wed, 27 Jan 2016 11:49:58 +0000 (+0000)
Subject: cmd/link: correct byte ordering in plan9_arm object header
X-Git-Tag: go1.6rc1~16
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=bd7e084d7d4eb88829026b5bdaf0915d5a389048;p=gostls13.git

cmd/link: correct byte ordering in plan9_arm object header

Fields in Plan 9 object headers are big-endian, on all architectures.

Change-Id: If95ad29750b776338178d660646568bf26a4abda
Reviewed-on: https://go-review.googlesource.com/18964
Reviewed-by: Russ Cox <rsc@golang.org>
---

diff --git a/src/cmd/link/internal/arm/asm.go b/src/cmd/link/internal/arm/asm.go
index 8ffa656208..74c2249702 100644
--- a/src/cmd/link/internal/arm/asm.go
+++ b/src/cmd/link/internal/arm/asm.go
@@ -689,14 +689,14 @@ func asmb() {
 	switch ld.HEADTYPE {
 	default:
 	case obj.Hplan9: /* plan 9 */
-		ld.Thearch.Lput(0x647)                      /* magic */
-		ld.Thearch.Lput(uint32(ld.Segtext.Filelen)) /* sizes */
-		ld.Thearch.Lput(uint32(ld.Segdata.Filelen))
-		ld.Thearch.Lput(uint32(ld.Segdata.Length - ld.Segdata.Filelen))
-		ld.Thearch.Lput(uint32(ld.Symsize))      /* nsyms */
-		ld.Thearch.Lput(uint32(ld.Entryvalue())) /* va of entry */
-		ld.Thearch.Lput(0)
-		ld.Thearch.Lput(uint32(ld.Lcsize))
+		ld.Lputb(0x647)                      /* magic */
+		ld.Lputb(uint32(ld.Segtext.Filelen)) /* sizes */
+		ld.Lputb(uint32(ld.Segdata.Filelen))
+		ld.Lputb(uint32(ld.Segdata.Length - ld.Segdata.Filelen))
+		ld.Lputb(uint32(ld.Symsize))      /* nsyms */
+		ld.Lputb(uint32(ld.Entryvalue())) /* va of entry */
+		ld.Lputb(0)
+		ld.Lputb(uint32(ld.Lcsize))
 
 	case obj.Hlinux,
 		obj.Hfreebsd,
diff --git a/src/runtime/asm_arm.s b/src/runtime/asm_arm.s
index 09fbc952e0..53128e7eb1 100644
--- a/src/runtime/asm_arm.s
+++ b/src/runtime/asm_arm.s
@@ -81,12 +81,17 @@ DATA	runtime·mainPC+0(SB)/4,$runtime·main(SB)
 GLOBL	runtime·mainPC(SB),RODATA,$4
 
 TEXT runtime·breakpoint(SB),NOSPLIT,$0-0
+	BL		runtime·emptyfunc(SB)	// force R14 save for traceback
 	// gdb won't skip this breakpoint instruction automatically,
 	// so you must manually "set $pc+=4" to skip it and continue.
 #ifdef GOOS_nacl
 	WORD	$0xe125be7f	// BKPT 0x5bef, NACL_INSTR_ARM_BREAKPOINT
+#else
+#ifdef GOOS_plan9
+	WORD	$0xD1200070	// undefined instruction used as armv5 breakpoint in Plan 9
 #else
 	WORD	$0xe7f001f0	// undefined instruction that gdb understands is a software breakpoint
+#endif
 #endif
 	RET