cmd/cc,runtime: change preprocessor to expand macros inside of

#pragma textflag and #pragma dataflag directives.
Update dataflag directives to use symbols instead of integer constants.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/13310043

src/cmd/cc/dpchk.c

@@ -567,7 +567,19 @@ pragfpround(void)
 void
 pragtextflag(void)
 {
-	textflag = getnsn();
+	Sym *s;
+
+	s = getsym();
+	if(s == S) {
+		textflag = getnsn();
+	} else {
+		if(s->macro) {
+			macexpand(s, symb);
+		}
+		if(symb[0] < '0' || symb[0] > '9')
+			yyerror("pragma textflag not an integer");
+		textflag = atoi(symb);
+	}
 	while(getnsc() != '\n')
 		;
 	if(debug['f'])
@@ -577,7 +589,19 @@ pragtextflag(void)
 void
 pragdataflag(void)
 {
-	dataflag = getnsn();
+	Sym *s;
+
+	s = getsym();
+	if(s == S) {
+		dataflag = getnsn();
+	} else {
+		if(s->macro) {
+			macexpand(s, symb);
+		}
+		if(symb[0] < '0' || symb[0] > '9')
+			yyerror("pragma dataflag not an integer");
+		dataflag = atoi(symb);
+	}
 	while(getnsc() != '\n')
 		;
 	if(debug['f'])

src/cmd/ld/textflag.h

@@ -7,13 +7,13 @@
 // all agree on these values.
 
 // Don't profile the marked routine.  This flag is deprecated.
-#define NOPROF	(1<<0)
+#define NOPROF	1
 // It is ok for the linker to get multiple of these symbols.  It will
 // pick one of the duplicates to use.
-#define DUPOK	(1<<1)
+#define DUPOK	2
 // Don't insert stack check preamble.
-#define NOSPLIT	(1<<2)
+#define NOSPLIT	4
 // Put this data in a read-only section.
-#define RODATA	(1<<3)
+#define RODATA	8
 // This data contains no pointers.
-#define NOPTR	(1<<4)
+#define NOPTR	16

src/pkg/runtime/hashmap.c

@@ -8,6 +8,7 @@
 #include "hashmap.h"
 #include "type.h"
 #include "race.h"
+#include "../../cmd/ld/textflag.h"
 
 // This file contains the implementation of Go's map type.
 //
@@ -524,7 +525,7 @@ hash_lookup(MapType *t, Hmap *h, byte **keyp)
 }
 
 // When an item is not found, fast versions return a pointer to this zeroed memory.
-#pragma dataflag 16 // no pointers
+#pragma dataflag RODATA
 static uint8 empty_value[MAXVALUESIZE];
 
 // Specialized versions of mapaccess1 for specific types.
@@ -593,7 +594,6 @@ static uint8 empty_value[MAXVALUESIZE];
 #define SLOW_EQ(x,y) runtime·memeq((x).str, (y).str, (x).len)
 #define MAYBE_EQ(x,y) (*(CHECKTYPE*)(x).str == *(CHECKTYPE*)(y).str && *(CHECKTYPE*)((x).str + (x).len - sizeof(CHECKTYPE)) == *(CHECKTYPE*)((y).str + (x).len - sizeof(CHECKTYPE)))
 #include "hashmap_fast.c"
-#include "../../cmd/ld/textflag.h"
 
 static void
 hash_insert(MapType *t, Hmap *h, void *key, void *value)

src/pkg/runtime/malloc.goc

@@ -17,7 +17,7 @@ package runtime
 #include "../../cmd/ld/textflag.h"
 
 // Mark mheap as 'no pointers', it does not contain interesting pointers but occupies ~45K.
-#pragma dataflag 16
+#pragma dataflag NOPTR
 MHeap runtime·mheap;
 
 int32	runtime·checking;

src/pkg/runtime/mgc0.c

@@ -14,6 +14,7 @@
 #include "typekind.h"
 #include "hashmap.h"
 #include "funcdata.h"
+#include "../../cmd/ld/textflag.h"
 
 enum {
 	Debug = 0,
@@ -299,7 +300,7 @@ struct BufferList
 	uint32 busy;
 	byte pad[CacheLineSize];
 };
-#pragma dataflag 16  // no pointers
+#pragma dataflag NOPTR
 static BufferList bufferList[MaxGcproc];
 
 static Type *itabtype;

src/pkg/runtime/os_linux.c

@@ -169,7 +169,7 @@ runtime·get_random_data(byte **rnd, int32 *rnd_len)
 		*rnd = runtime·startup_random_data;
 		*rnd_len = runtime·startup_random_data_len;
 	} else {
-		#pragma dataflag 16 // no pointers
+		#pragma dataflag NOPTR
 		static byte urandom_data[HashRandomBytes];
 		int32 fd;
 		fd = runtime·open("/dev/urandom", 0 /* O_RDONLY */, 0);

src/pkg/runtime/os_plan9.c

@@ -324,7 +324,7 @@ runtime·memlimit(void)
 	return 0;
 }
 
-#pragma dataflag 16 // no pointers
+#pragma dataflag NOPTR
 static int8 badsignal[] = "runtime: signal received on thread not created by Go.\n";
 
 // This runs on a foreign stack, without an m or a g.  No stack split.

src/pkg/runtime/os_windows.c

@@ -478,7 +478,7 @@ runtime·memlimit(void)
 	return 0;
 }
 
-#pragma dataflag 16 // no pointers
+#pragma dataflag NOPTR
 int8 runtime·badsignalmsg[] = "runtime: signal received on thread not created by Go.\n";
 int32 runtime·badsignallen = sizeof runtime·badsignalmsg - 1;
 

src/pkg/runtime/sema.goc

@@ -20,6 +20,7 @@
 package sync
 #include "runtime.h"
 #include "arch_GOARCH.h"
+#include "../../cmd/ld/textflag.h"
 
 typedef struct SemaWaiter SemaWaiter;
 struct SemaWaiter
@@ -50,7 +51,7 @@ struct semtable
 	SemaRoot;
 	uint8 pad[CacheLineSize-sizeof(SemaRoot)];
 };
-#pragma dataflag 16 /* mark semtable as 'no pointers', hiding from garbage collector */
+#pragma dataflag NOPTR /* mark semtable as 'no pointers', hiding from garbage collector */
 static struct semtable semtable[SEMTABLESZ];
 
 static SemaRoot*