From cbf97d9103b2bbfb8c798f06c751e74093062b57 Mon Sep 17 00:00:00 2001
From: Russ Cox <rsc@golang.org>
Date: Tue, 16 Sep 2014 20:53:38 -0400
Subject: [PATCH] liblink, sync/atomic: fix arm build

The liblink code to insert the FUNCDATA for a stack map
from the Go prototype was not correct for ARM
(different data structure layout).

Also, sync/atomic was missing some Go prototypes
for ARM-specific functions.

TBR=r
CC=golang-codereviews
https://golang.org/cl/143160045
---
 include/link.h               | 1 +
 src/liblink/obj5.c           | 1 +
 src/liblink/objfile.c        | 7 ++++++-
 src/sync/atomic/64bit_arm.go | 6 ++++++
 4 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/include/link.h b/include/link.h
index 8c73eab51e..292b077394 100644
--- a/include/link.h
+++ b/include/link.h
@@ -471,6 +471,7 @@ struct LinkArch
 	int	D_PARAM;
 	int	D_SCONST;
 	int	D_STATIC;
+	int	D_OREG;
 
 	int	ACALL;
 	int	ADATA;
diff --git a/src/liblink/obj5.c b/src/liblink/obj5.c
index a571d8f166..e192b082b5 100644
--- a/src/liblink/obj5.c
+++ b/src/liblink/obj5.c
@@ -1061,6 +1061,7 @@ LinkArch linkarm = {
 	.D_PARAM = D_PARAM,
 	.D_SCONST = D_SCONST,
 	.D_STATIC = D_STATIC,
+	.D_OREG = D_OREG,
 
 	.ACALL = ABL,
 	.ADATA = ADATA,
diff --git a/src/liblink/objfile.c b/src/liblink/objfile.c
index 7d4b28c9ac..9b1e1b7a8f 100644
--- a/src/liblink/objfile.c
+++ b/src/liblink/objfile.c
@@ -268,7 +268,12 @@ writeobj(Link *ctxt, Biobuf *b)
 			p->as = ctxt->arch->AFUNCDATA;
 			p->from.type = ctxt->arch->D_CONST;
 			p->from.offset = FUNCDATA_ArgsPointerMaps;
-			p->to.type = ctxt->arch->D_EXTERN;
+			if(ctxt->arch->thechar == '6' || ctxt->arch->thechar == '8')
+				p->to.type = ctxt->arch->D_EXTERN;
+			else {
+				p->to.type = ctxt->arch->D_OREG;
+				p->to.name = ctxt->arch->D_EXTERN;
+			}
 			p->to.sym = linklookup(ctxt, smprint("%s.args_stackmap", s->name), s->version);
 		}
 	}
diff --git a/src/sync/atomic/64bit_arm.go b/src/sync/atomic/64bit_arm.go
index c08f214c7e..0aab7160e9 100644
--- a/src/sync/atomic/64bit_arm.go
+++ b/src/sync/atomic/64bit_arm.go
@@ -44,3 +44,9 @@ func swapUint64(addr *uint64, new uint64) (old uint64) {
 	}
 	return
 }
+
+// Additional ARM-specific assembly routines.
+// Declaration here to give assembly routines correct stack maps for arguments.
+func armCompareAndSwapUint32(addr *uint32, old, new uint32) (swapped bool)
+func armCompareAndSwapUint64(addr *uint64, old, new uint64) (swapped bool)
+func generalCAS64(addr *uint64, old, new uint64) (swapped bool)