cmd/5g, cmd/6g, cmd/8g: insert arg size annotations on runtime calls

If calling a function in package runtime, emit argument size
information around the call in case the call is to a variadic C function.

R=ken2
CC=golang-dev
https://golang.org/cl/11371043

src/cmd/5g/gg.h

@@ -146,6 +146,7 @@ void	split64(Node*, Node*, Node*);
 void	splitclean(void);
 Node*	ncon(uint32 i);
 void	gtrack(Sym*);
+void	gargsize(int32);
 
 /*
  * obj.c

src/cmd/5g/ggen.c

@@ -73,9 +73,23 @@ fixautoused(Prog* p)
 void
 ginscall(Node *f, int proc)
 {
+	int32 arg;
 	Prog *p;
 	Node n1, r, r1, con;
 
+	if(f->type != T)
+		setmaxarg(f->type);
+
+	arg = -1;
+	if(f->type != T && ((f->sym != S && f->sym->pkg == runtimepkg) || proc == 1 || proc == 2)) {
+		arg = f->type->argwid;
+		if(proc == 1 || proc == 2)
+			arg += 3*widthptr;
+	}
+
+	if(arg != -1)
+		gargsize(arg);
+
 	switch(proc) {
 	default:
 		fatal("ginscall: bad proc %d", proc);
@@ -170,6 +184,9 @@ ginscall(Node *f, int proc)
 		}
 		break;
 	}
+	
+	if(arg != -1)
+		gargsize(-1);
 }
 
 /*
@@ -239,14 +256,11 @@ cgen_callinter(Node *n, Node *res, int proc)
 		p->from.type = D_CONST;	// REG = &(20+offset(REG)) -- i.tab->fun[f]
 	}
 
-	// BOTCH nodr.type = fntype;
 	nodr.type = n->left->type;
 	ginscall(&nodr, proc);
 
 	regfree(&nodr);
 	regfree(&nodo);
-
-	setmaxarg(n->left->type);
 }
 
 /*
@@ -274,8 +288,6 @@ cgen_call(Node *n, int proc)
 	genlist(n->list);		// assign the args
 	t = n->left->type;
 
-	setmaxarg(t);
-
 	// call tempname pointer
 	if(n->left->ullman >= UINF) {
 		regalloc(&nod, types[tptr], N);

src/cmd/5g/gsubr.c

@@ -31,6 +31,7 @@
 #include <u.h>
 #include <libc.h>
 #include "gg.h"
+#include "../../pkg/runtime/funcdata.h"
 
 // TODO(rsc): Can make this bigger if we move
 // the text segment up higher in 5l for all GOOS.
@@ -209,6 +210,16 @@ ggloblnod(Node *nam)
 		p->reg |= NOPTR;
 }
 
+void
+gargsize(int32 size)
+{
+	Node n1, n2;
+	
+	nodconst(&n1, types[TINT32], PCDATA_ArgSize);
+	nodconst(&n2, types[TINT32], size);
+	gins(APCDATA, &n1, &n2);
+}
+
 void
 ggloblsym(Sym *s, int32 width, int dupok, int rodata)
 {

src/cmd/5g/peep.c

@@ -1199,6 +1199,7 @@ copyu(Prog *p, Adr *v, Adr *s)
 	case ALOCALS:	/* funny */
 	case ANPTRS:
 	case APTRS:
+	case APCDATA:
 		return 0;
 	}
 }

src/cmd/6g/gg.h

@@ -131,6 +131,7 @@ int	sudoaddable(int, Node*, Addr*);
 void	afunclit(Addr*, Node*);
 void	nodfconst(Node*, Type*, Mpflt*);
 void	gtrack(Sym*);
+void	gargsize(vlong);
 
 /*
  * cplx.c

src/cmd/6g/ggen.c

@@ -70,10 +70,24 @@ fixautoused(Prog *p)
 void
 ginscall(Node *f, int proc)
 {
+	int32 arg;
 	Prog *p;
 	Node reg, con;
 	Node r1;
 
+	if(f->type != T)
+		setmaxarg(f->type);
+
+	arg = -1;
+	if(f->type != T && ((f->sym != S && f->sym->pkg == runtimepkg) || proc == 1 || proc == 2)) {
+		arg = f->type->argwid;
+		if(proc == 1 || proc == 2)
+			arg += 2*widthptr;
+	}
+
+	if(arg != -1)
+		gargsize(arg);
+
 	switch(proc) {
 	default:
 		fatal("ginscall: bad proc %d", proc);
@@ -143,6 +157,9 @@ ginscall(Node *f, int proc)
 		}
 		break;
 	}
+
+	if(arg != -1)
+		gargsize(-1);
 }
 
 /*
@@ -202,14 +219,11 @@ cgen_callinter(Node *n, Node *res, int proc)
 		gins(ALEAQ, &nodo, &nodr);	// REG = &(32+offset(REG)) -- i.tab->fun[f]
 	}
 
-	// BOTCH nodr.type = fntype;
 	nodr.type = n->left->type;
 	ginscall(&nodr, proc);
 
 	regfree(&nodr);
 	regfree(&nodo);
-
-	setmaxarg(n->left->type);
 }
 
 /*
@@ -237,8 +251,6 @@ cgen_call(Node *n, int proc)
 	genlist(n->list);		// assign the args
 	t = n->left->type;
 
-	setmaxarg(t);
-
 	// call tempname pointer
 	if(n->left->ullman >= UINF) {
 		regalloc(&nod, types[tptr], N);

src/cmd/6g/gsubr.c

@@ -31,6 +31,7 @@
 #include <u.h>
 #include <libc.h>
 #include "gg.h"
+#include "../../pkg/runtime/funcdata.h"
 
 // TODO(rsc): Can make this bigger if we move
 // the text segment up higher in 6l for all GOOS.
@@ -218,6 +219,16 @@ gtrack(Sym *s)
 	p->from.sym = s;
 }
 
+void
+gargsize(vlong size)
+{
+	Node n1, n2;
+	
+	nodconst(&n1, types[TINT32], PCDATA_ArgSize);
+	nodconst(&n2, types[TINT32], size);
+	gins(APCDATA, &n1, &n2);
+}
+
 void
 ggloblsym(Sym *s, int32 width, int dupok, int rodata)
 {

src/cmd/8g/gg.h

@@ -151,7 +151,7 @@ void	split64(Node*, Node*, Node*);
 void	splitclean(void);
 void	nswap(Node*, Node*);
 void	gtrack(Sym*);
-
+void	gargsize(int32);
 /*
  * cplx.c
  */

src/cmd/8g/ggen.c

@@ -115,9 +115,23 @@ clearfat(Node *nl)
 void
 ginscall(Node *f, int proc)
 {
+	int32 arg;
 	Prog *p;
 	Node reg, r1, con;
 
+	if(f->type != T)
+		setmaxarg(f->type);
+
+	arg = -1;
+	if(f->type != T && ((f->sym != S && f->sym->pkg == runtimepkg) || proc == 1 || proc == 2)) {
+		arg = f->type->argwid;
+		if(proc == 1 || proc == 2)
+			arg += 2*widthptr;
+	}
+
+	if(arg != -1)
+		gargsize(arg);
+
 	switch(proc) {
 	default:
 		fatal("ginscall: bad proc %d", proc);
@@ -177,6 +191,9 @@ ginscall(Node *f, int proc)
 		}
 		break;
 	}
+	
+	if(arg != -1)
+		gargsize(-1);
 }
 
 /*
@@ -237,14 +254,11 @@ cgen_callinter(Node *n, Node *res, int proc)
 		gins(ALEAL, &nodo, &nodr);	// REG = &(20+offset(REG)) -- i.tab->fun[f]
 	}
 
-	// BOTCH nodr.type = fntype;
 	nodr.type = n->left->type;
 	ginscall(&nodr, proc);
 
 	regfree(&nodr);
 	regfree(&nodo);
-
-	setmaxarg(n->left->type);
 }
 
 /*
@@ -272,8 +286,6 @@ cgen_call(Node *n, int proc)
 	genlist(n->list);		// assign the args
 	t = n->left->type;
 
-	setmaxarg(t);
-
 	// call tempname pointer
 	if(n->left->ullman >= UINF) {
 		regalloc(&nod, types[tptr], N);

src/cmd/8g/gsubr.c

@@ -31,6 +31,7 @@
 #include <u.h>
 #include <libc.h>
 #include "gg.h"
+#include "../../pkg/runtime/funcdata.h"
 
 // TODO(rsc): Can make this bigger if we move
 // the text segment up higher in 8l for all GOOS.
@@ -208,6 +209,16 @@ ggloblnod(Node *nam)
 		p->from.scale |= NOPTR;
 }
 
+void
+gargsize(int32 size)
+{
+	Node n1, n2;
+	
+	nodconst(&n1, types[TINT32], PCDATA_ArgSize);
+	nodconst(&n2, types[TINT32], size);
+	gins(APCDATA, &n1, &n2);
+}
+
 void
 ggloblsym(Sym *s, int32 width, int dupok, int rodata)
 {