runtime: change PC, SP values in Stkframe, Panic, Defer from byte* to uintptr

uintptr is better when translating to Go,
and in a few places it's better in C too.

LGTM=r
R=golang-codereviews, r
CC=golang-codereviews, iant, khr
https://golang.org/cl/138980043

src/pkg/runtime/heapdump.c

@@ -309,7 +309,7 @@ dumpframe(Stkframe *s, void *arg)
 		dumpbvtypes(&child->args, (byte*)s->sp + child->argoff);
 	if(stackmap != nil && stackmap->n > 0) {
 		bv = runtime·stackmapdata(stackmap, pcdata);
-		dumpbvtypes(&bv, s->varp - bv.n / BitsPerPointer * PtrSize);
+		dumpbvtypes(&bv, (byte*)(s->varp - bv.n / BitsPerPointer * PtrSize));
 	} else {
 		bv.n = -1;
 	}
@@ -342,26 +342,26 @@ dumpframe(Stkframe *s, void *arg)
 	// Dump fields in the local vars section
 	if(stackmap == nil) {
 		// No locals information, dump everything.
-		for(off = child->arglen; off < s->varp - (byte*)s->sp; off += PtrSize) {
+		for(off = child->arglen; off < s->varp - s->sp; off += PtrSize) {
 			dumpint(FieldKindPtr);
 			dumpint(off);
 		}
 	} else if(stackmap->n < 0) {
 		// Locals size information, dump just the locals.
 		size = -stackmap->n;
-		for(off = s->varp - size - (byte*)s->sp; off < s->varp - (byte*)s->sp; off += PtrSize) {
+		for(off = s->varp - size - s->sp; off <  s->varp - s->sp; off += PtrSize) {
 			dumpint(FieldKindPtr);
 			dumpint(off);
 		}
 	} else if(stackmap->n > 0) {
 		// Locals bitmap information, scan just the pointers in
 		// locals.
-		dumpbv(&bv, s->varp - bv.n / BitsPerPointer * PtrSize - (byte*)s->sp);
+		dumpbv(&bv, s->varp - bv.n / BitsPerPointer * PtrSize - s->sp);
 	}
 	dumpint(FieldKindEol);
 
 	// Record arg info for parent.
-	child->argoff = s->argp - (byte*)s->fp;
+	child->argoff = s->argp - s->fp;
 	child->arglen = s->arglen;
 	child->sp = (byte*)s->sp;
 	child->depth++;

src/pkg/runtime/mgc0.c

@@ -674,16 +674,16 @@ scanframe(Stkframe *frame, void *unused)
 	stackmap = runtime·funcdata(f, FUNCDATA_LocalsPointerMaps);
 	if(stackmap == nil) {
 		// No locals information, scan everything.
-		size = frame->varp - (byte*)frame->sp;
+		size = frame->varp - frame->sp;
 		if(Debug > 2)
-			runtime·printf("frame %s unsized locals %p+%p\n", runtime·funcname(f), frame->varp-size, size);
-		scanblock(frame->varp - size, size, ScanConservatively);
+			runtime·printf("frame %s unsized locals %p+%p\n", runtime·funcname(f), (byte*)(frame->varp-size), size);
+		scanblock((byte*)(frame->varp - size), size, ScanConservatively);
 	} else if(stackmap->n < 0) {
 		// Locals size information, scan just the locals.
 		size = -stackmap->n;
 		if(Debug > 2)
-			runtime·printf("frame %s conservative locals %p+%p\n", runtime·funcname(f), frame->varp-size, size);
-		scanblock(frame->varp - size, size, ScanConservatively);
+			runtime·printf("frame %s conservative locals %p+%p\n", runtime·funcname(f), (byte*)(frame->varp-size), size);
+		scanblock((byte*)(frame->varp - size), size, ScanConservatively);
 	} else if(stackmap->n > 0) {
 		// Locals bitmap information, scan just the pointers in locals.
 		if(pcdata < 0 || pcdata >= stackmap->n) {
@@ -694,7 +694,7 @@ scanframe(Stkframe *frame, void *unused)
 		}
 		bv = runtime·stackmapdata(stackmap, pcdata);
 		size = (bv.n * PtrSize) / BitsPerPointer;
-		scanblock(frame->varp - size, bv.n/BitsPerPointer*PtrSize, (byte*)bv.data);
+		scanblock((byte*)(frame->varp - size), bv.n/BitsPerPointer*PtrSize, (byte*)bv.data);
 	}
 
 	// Scan arguments.
@@ -702,11 +702,11 @@ scanframe(Stkframe *frame, void *unused)
 	stackmap = runtime·funcdata(f, FUNCDATA_ArgsPointerMaps);
 	if(stackmap != nil) {
 		bv = runtime·stackmapdata(stackmap, pcdata);
-		scanblock(frame->argp, bv.n/BitsPerPointer*PtrSize, (byte*)bv.data);
+		scanblock((byte*)frame->argp, bv.n/BitsPerPointer*PtrSize, (byte*)bv.data);
 	} else {
 		if(Debug > 2)
 			runtime·printf("frame %s conservative args %p+%p\n", runtime·funcname(f), frame->argp, (uintptr)frame->arglen);
-		scanblock(frame->argp, frame->arglen, ScanConservatively);
+		scanblock((byte*)frame->argp, frame->arglen, ScanConservatively);
 	}
 	return true;
 }
@@ -1798,7 +1798,7 @@ getgcmaskcb(Stkframe *frame, void *ctxt)
 	Stkframe *frame0;
 
 	frame0 = ctxt;
-	if(frame0->sp >= (uintptr)frame->varp - frame->sp && frame0->sp < (uintptr)frame->varp) {
+	if(frame0->sp >= frame->varp - frame->sp && frame0->sp < frame->varp) {
 		*frame0 = *frame;
 		return false;
 	}
@@ -1883,7 +1883,7 @@ runtime·getgcmask(byte *p, Type *t, byte **mask, uintptr *len)
 		*len = n/PtrSize;
 		*mask = runtime·mallocgc(*len, nil, 0);
 		for(i = 0; i < n; i += PtrSize) {
-			off = (p+i-frame.varp+size)/PtrSize;
+			off = (p+i-(byte*)frame.varp+size)/PtrSize;
 			bits = (bv.data[off*BitsPerPointer/32] >> ((off*BitsPerPointer)%32))&BitsMask;
 			(*mask)[i/PtrSize] = bits;
 		}

src/pkg/runtime/panic.c

@@ -85,12 +85,12 @@ runtime·deferproc(int32 siz, FuncVal *fn, ...)
 
 	d = newdefer(siz);
 	d->fn = fn;
-	d->pc = runtime·getcallerpc(&siz);
+	d->pc = (uintptr)runtime·getcallerpc(&siz);
 	if(thechar == '5')
-		d->argp = (byte*)(&fn+2);  // skip caller's saved link register
+		d->argp = (uintptr)(&fn+2);  // skip caller's saved link register
 	else
-		d->argp = (byte*)(&fn+1);
-	runtime·memmove(d->args, d->argp, d->siz);
+		d->argp = (uintptr)(&fn+1);
+	runtime·memmove(d->args, (byte*)d->argp, d->siz);
 
 	// deferproc returns 0 normally.
 	// a deferred func that stops a panic
@@ -119,13 +119,13 @@ void
 runtime·deferreturn(uintptr arg0)
 {
 	Defer *d;
-	byte *argp;
+	uintptr argp;
 	FuncVal *fn;
 
 	d = g->defer;
 	if(d == nil)
 		return;
-	argp = (byte*)&arg0;
+	argp = (uintptr)&arg0;
 	if(d->argp != argp)
 		return;
 
@@ -134,7 +134,7 @@ runtime·deferreturn(uintptr arg0)
 	// won't know the form of the arguments until the jmpdefer can
 	// flip the PC over to fn.
 	g->m->locks++;
-	runtime·memmove(argp, d->args, d->siz);
+	runtime·memmove((byte*)argp, d->args, d->siz);
 	fn = d->fn;
 	g->defer = d->link;
 	freedefer(d);
@@ -213,7 +213,7 @@ runtime·panic(Eface e)
 {
 	Defer *d, dabort;
 	Panic p;
-	void *pc, *argp;
+	uintptr pc, argp;
 
 	runtime·memclr((byte*)&p, sizeof p);
 	p.arg = e;

src/pkg/runtime/runtime.h

@@ -624,17 +624,15 @@ struct Defer
 {
 	int32	siz;
 	bool	special;	// not part of defer frame
-	byte*	argp;		// where args were copied from
-	byte*	pc;
+	uintptr	argp;		// where args were copied from
+	uintptr	pc;
 	FuncVal*	fn;
 	Defer*	link;
 	void*	args[1];	// padded to actual size
 };
 
 // argp used in Defer structs when there is no argp.
-// TODO(rsc): Maybe we could use nil instead, but we've always used -1
-// and I don't want to change this days before the Go 1.3 release.
-#define NoArgs ((byte*)-1)
+#define NoArgs ((uintptr)-1)
 
 /*
  * panics
@@ -649,6 +647,8 @@ struct Panic
 	bool	aborted;	// the panic was aborted
 };
 
+typedef struct XXX XXX;
+
 /*
  * stack traces
  */
@@ -661,8 +661,8 @@ struct Stkframe
 	uintptr	lr;	// program counter at caller aka link register
 	uintptr	sp;	// stack pointer at pc
 	uintptr	fp;	// stack pointer at caller aka frame pointer
-	byte*	varp;	// top of local variables
-	byte*	argp;	// pointer to function arguments
+	uintptr	varp;	// top of local variables
+	uintptr	argp;	// pointer to function arguments
 	uintptr	arglen;	// number of bytes at argp
 };
 
@@ -775,7 +775,7 @@ int32	runtime·read(int32, void*, int32);
 int32	runtime·write(uintptr, void*, int32); // use uintptr to accommodate windows.
 int32	runtime·close(int32);
 int32	runtime·mincore(void*, uintptr, byte*);
-void	runtime·jmpdefer(FuncVal*, void*);
+void	runtime·jmpdefer(FuncVal*, uintptr);
 void	runtime·exit1(int32);
 void	runtime·ready(G*);
 byte*	runtime·getenv(int8*);

src/pkg/runtime/stack.c

@@ -419,7 +419,7 @@ checkframecopy(Stkframe *frame, void *arg)
 	if(StackDebug >= 2)
 		runtime·printf("    checking %s frame=[%p,%p] stk=[%p,%p]\n", runtime·funcname(f), frame->sp, frame->fp, cinfo->stk, cinfo->base);
 	// if we're not in the segment any more, return immediately.
-	if(frame->varp < cinfo->stk || frame->varp >= cinfo->base) {
+	if((byte*)frame->varp < cinfo->stk || (byte*)frame->varp >= cinfo->base) {
 		if(StackDebug >= 2)
 			runtime·printf("    <next segment>\n");
 		return false; // stop traceback
@@ -438,7 +438,7 @@ checkframecopy(Stkframe *frame, void *arg)
 		cinfo->frames++;
 		return true;
 	}
-	if(frame->varp != (byte*)frame->sp) { // not in prologue (and has at least one local or outarg)
+	if((byte*)frame->varp != (byte*)frame->sp) { // not in prologue (and has at least one local or outarg)
 		stackmap = runtime·funcdata(f, FUNCDATA_LocalsPointerMaps);
 		if(stackmap == nil) {
 			cinfo->frames = -1;
@@ -501,7 +501,7 @@ copyabletopsegment(G *gp)
 			// For now, this only happens with the Defer in runtime.main.
 			continue;
 		}
-		if(d->argp < cinfo.stk || cinfo.base <= d->argp)
+		if((byte*)d->argp < cinfo.stk || cinfo.base <= (byte*)d->argp)
 			break; // a defer for the next segment
 		fn = d->fn;
 		if(fn == nil) // See issue 8047
@@ -666,7 +666,7 @@ adjustframe(Stkframe *frame, void *arg)
 		pcdata = 0; // in prologue
 
 	// adjust local pointers
-	if(frame->varp != (byte*)frame->sp) {
+	if((byte*)frame->varp != (byte*)frame->sp) {
 		stackmap = runtime·funcdata(f, FUNCDATA_LocalsPointerMaps);
 		if(stackmap == nil)
 			runtime·throw("no locals info");
@@ -715,7 +715,7 @@ adjustdefers(G *gp, AdjustInfo *adjinfo)
 			*dp = (Defer*)((byte*)d + adjinfo->delta);
 			continue;
 		}
-		if(d->argp < adjinfo->oldstk || adjinfo->oldbase <= d->argp)
+		if((byte*)d->argp < adjinfo->oldstk || adjinfo->oldbase <= (byte*)d->argp)
 			break; // a defer for the next segment
 		fn = d->fn;
 		if(fn == nil) {

src/pkg/runtime/traceback_arm.c

@@ -139,7 +139,7 @@ runtime·gentraceback(uintptr pc0, uintptr sp0, uintptr lr0, G *gp, int32 skip,
 			}
 		}
 
-		frame.varp = (byte*)frame.fp;
+		frame.varp = frame.fp;
 
 		// Derive size of arguments.
 		// Most functions have a fixed-size argument block,
@@ -148,7 +148,7 @@ runtime·gentraceback(uintptr pc0, uintptr sp0, uintptr lr0, G *gp, int32 skip,
 		// in package runtime and reflect, and for those we use call-specific
 		// metadata recorded by f's caller.
 		if(callback != nil || printing) {
-			frame.argp = (byte*)frame.fp + sizeof(uintptr);
+			frame.argp = frame.fp + sizeof(uintptr);
 			if(f->args != ArgsSizeUnknown)
 				frame.arglen = f->args;
 			else if(flr == nil)
@@ -193,18 +193,18 @@ runtime·gentraceback(uintptr pc0, uintptr sp0, uintptr lr0, G *gp, int32 skip,
 		// returns; everything live at earlier deferprocs is still live at that one.
 		frame.continpc = frame.pc;
 		if(waspanic) {
-			if(panic != nil && panic->defer->argp == (byte*)sparg)
+			if(panic != nil && panic->defer->argp == sparg)
 				frame.continpc = (uintptr)panic->defer->pc;
-			else if(defer != nil && defer->argp == (byte*)sparg)
+			else if(defer != nil && defer->argp == sparg)
 				frame.continpc = (uintptr)defer->pc;
 			else
 				frame.continpc = 0;
 		}
 
 		// Unwind our local panic & defer stacks past this frame.
-		while(panic != nil && (panic->defer == nil || panic->defer->argp == (byte*)sparg || panic->defer->argp == NoArgs))
+		while(panic != nil && (panic->defer == nil || panic->defer->argp == sparg || panic->defer->argp == NoArgs))
 			panic = panic->link;
-		while(defer != nil && (defer->argp == (byte*)sparg || defer->argp == NoArgs))
+		while(defer != nil && (defer->argp == sparg || defer->argp == NoArgs))
 			defer = defer->link;	
 
 		if(skip > 0) {

src/pkg/runtime/traceback_x86.c

@@ -181,7 +181,7 @@ runtime·gentraceback(uintptr pc0, uintptr sp0, uintptr lr0, G *gp, int32 skip,
 			}
 		}
 		
-		frame.varp = (byte*)frame.fp - sizeof(uintreg);
+		frame.varp = frame.fp - sizeof(uintreg);
 
 		// Derive size of arguments.
 		// Most functions have a fixed-size argument block,
@@ -190,7 +190,7 @@ runtime·gentraceback(uintptr pc0, uintptr sp0, uintptr lr0, G *gp, int32 skip,
 		// in package runtime and reflect, and for those we use call-specific
 		// metadata recorded by f's caller.
 		if(callback != nil || printing) {
-			frame.argp = (byte*)frame.fp;
+			frame.argp = frame.fp;
 			if(f->args != ArgsSizeUnknown)
 				frame.arglen = f->args;
 			else if(flr == nil)
@@ -228,18 +228,18 @@ runtime·gentraceback(uintptr pc0, uintptr sp0, uintptr lr0, G *gp, int32 skip,
 		// returns; everything live at earlier deferprocs is still live at that one.
 		frame.continpc = frame.pc;
 		if(waspanic) {
-			if(panic != nil && panic->defer->argp == (byte*)sparg)
-				frame.continpc = (uintptr)panic->defer->pc;
-			else if(defer != nil && defer->argp == (byte*)sparg)
-				frame.continpc = (uintptr)defer->pc;
+			if(panic != nil && panic->defer->argp == sparg)
+				frame.continpc = panic->defer->pc;
+			else if(defer != nil && defer->argp == sparg)
+				frame.continpc = defer->pc;
 			else
 				frame.continpc = 0;
 		}
 
 		// Unwind our local panic & defer stacks past this frame.
-		while(panic != nil && (panic->defer == nil || panic->defer->argp == (byte*)sparg || panic->defer->argp == NoArgs))
+		while(panic != nil && (panic->defer == nil || panic->defer->argp == sparg || panic->defer->argp == NoArgs))
 			panic = panic->link;
-		while(defer != nil && (defer->argp == (byte*)sparg || defer->argp == NoArgs))
+		while(defer != nil && (defer->argp == sparg || defer->argp == NoArgs))
 			defer = defer->link;	
 
 		if(skip > 0) {