all: merge dev.cc (a91c2e0) into master

This change deletes the C implementations of
the Go compiler and assembler from the master branch.

The Go implementations are a bit slower right now,
due mainly to garbage generated by taking addresses
of stack variables all over the place (it was C code,
after all). That will be cleaned up (mechanically) over the
next week or so, and things will get faster.

Change-Id: I66b2b3477aec8835f9960d0798f5752dcd98d08f

.gitignore

@@ -26,15 +26,14 @@ misc/cgo/life/run.out
 misc/cgo/stdio/run.out
 misc/cgo/testso/main
 misc/dashboard/builder/builder
-src/cmd/?a/y.output
 src/liblink/anames?.c
-src/cmd/cc/y.output
+src/cmd/*/y.output
 src/cmd/cgo/zdefaultcc.go
 src/cmd/dist/dist.dSYM
 src/cmd/gc/mkbuiltin1
 src/cmd/gc/opnames.h
-src/cmd/gc/y.output
 src/cmd/go/zdefaultcc.go
+src/cmd/internal/obj/zbootstrap.go
 src/go/doc/headscan
 src/runtime/mkversion
 src/runtime/zaexperiment.h

doc/go1.5.txt

@@ -23,6 +23,7 @@ testing/quick: support generation of arrays (https://golang.org/cl/3865)
 
 Tools:
 
+cmd/go: std wildcard now excludes commands in main repo (https://golang.org/cl/5550)
 cmd/vet: better validation of struct tags (https://golang.org/cl/2685)
 cmd/ld: no longer record build timestamp in Windows PE file header (https://golang.org/cl/3740)
 
@@ -34,3 +35,21 @@ strconv: optimize decimal to string conversion (https://golang.org/cl/2105)
 math/big: faster assembly kernels for amd64 and 386 (https://golang.org/cl/2503, https://golang.org/cl/2560)
 math/big: faster "pure Go" kernels for platforms w/o assembly kernels (https://golang.org/cl/2480)
 
+Assembler:
+
+ARM assembly syntax has had some features removed.
+
+	- mentioning SP or PC as a hardware register
+		These are always pseudo-registers except that in some contexts
+		they're not, and it's confusing because the context should not affect
+		which register you mean. Change the references to the hardware
+		registers to be explicit: R13 for SP, R15 for PC.
+	- constant creation using assignment
+		The files say a=b when they could instead say #define a b.
+		There is no reason to have both mechanisms.
+	- R(0) to refer to R0.
+		Some macros use this to a great extent. Again, it's easy just to
+		use a #define to rename a register.
+
+Also expression evaluation now uses uint64s instead of signed integers and the
+precedence of operators is now Go-like rather than C-like.

include/libc.h

@@ -292,6 +292,8 @@ extern	char*	getgoversion(void);
 extern	char*	getgoarm(void);
 extern	char*	getgo386(void);
 extern	char*	getgoextlinkenabled(void);
+extern	char*	getgohostos(void);
+extern	char*	getgohostarch(void);
 
 extern	char*	mktempdir(void);
 extern	void	removeall(char*);

include/link.h

@@ -241,6 +241,7 @@ struct	Prog
 	uchar	ft;	// oclass cache
 	uchar	tt;	// oclass cache
 	uchar	isize;	// amd64, 386
+	uchar	printed;
 
 	char	width;	/* fake for DATA */
 	char	mode;	/* 16, 32, or 64 in 6l, 8l; internal use in 5g, 6g, 8g */
@@ -303,6 +304,7 @@ struct	LSym
 	uchar	localentry;	// ppc64: instrs between global & local entry
 	uchar	seenglobl;
 	uchar	onlist;	// on the textp or datap lists
+	uchar	printed;
 	int16	symid;	// for writing .5/.6/.8 files
 	int32	dynid;
 	int32	sig;
@@ -458,6 +460,7 @@ struct	Hist
 	char*	name;
 	int32	line;
 	int32	offset;
+	uchar	printed;
 };
 
 struct	Plist

include/plan9/libc.h

@@ -14,6 +14,10 @@ char*	getgoversion(void);
 char*	getgoarm(void);
 char*	getgo386(void);
 char*	getgoextlinkenabled(void);
+char*	getgohostos(void);
+char*	getgohostarch(void);
+
+int	runcmd(char**);
 
 void	flagcount(char*, char*, int*);
 void	flagint32(char*, char*, int32*);

misc/cgo/test/issue9400/asm_arm.s

@@ -1,7 +1,7 @@
 #include "textflag.h"
 
 TEXT cas<>(SB),NOSPLIT,$0
-	MOVW	$0xffff0fc0, PC
+	MOVW	$0xffff0fc0, R15 // R15 is PC
 
 TEXT ·RewindAndSetgid(SB),NOSPLIT,$-4-0
 	// Save link register

misc/nacl/testzip.proto

@@ -10,9 +10,23 @@ usr	src=../misc/nacl/testdata
 go	src=..
 	src
 		cmd
+			asm
+				internal
+					asm
+						testdata
+							+
 			internal
 				objfile
 					objfile.go
+				rsc.io
+					arm
+						armasm
+							testdata
+								+
+					x86
+						x86asm
+							testdata
+								+
 			gofmt
 				gofmt.go
 				gofmt_test.go