shithub: riscv

Info  •  Files  •  Log  •  Branches

cc: remove mysbrk(), exponentially increase gethunk() allocation delta

mysbrk() was only used in gethunk() and should not be
called by anyone, so dont export the symbol.

simplify gethunk() using brk().

double allocation size on each call until we reach
1000*NHUNK.

use signed long for nhunk as alignment rountin might
make it negative and handle that case.

--- a/sys/src/cmd/cc/compat

+++ b/sys/src/cmd/cc/compat

@@ -4,12 +4,6 @@

 	return access(f, AEXIST);

 }

-void*

-mysbrk(ulong size)

-{

-	return sbrk(size);

-}

-

 int

 mycreat(char *n, int p)

 {

@@ -77,27 +71,35 @@

 	return fork();

 }

+

 /*

  * real allocs

  */

+

+extern char end[];

+

+char*	hunk = end;

+long	nhunk;

+uintptr	thunk;

+

 void

 gethunk(void)

 {

-	char *h;

-	ulong nh;

+	long nh;

-	nh = NHUNK;

-	if(thunk >= 10L*NHUNK)

-		nh = 10L*NHUNK;

-	h = (char*)mysbrk(nh);

-	if(h == (char*)-1)

-		sysfatal("out of memory");

-	if(nhunk == 0)

-		hunk = h;

+	if(thunk < NHUNK)

+		nh = NHUNK;

+	else if(thunk < 1000*NHUNK)

+		nh = thunk;

 	else

-		nh += (h - hunk) - nhunk;

+		nh = 1000*NHUNK;

+

+	if(nhunk < 0)

+		nhunk = 0;

 	nhunk += nh;

 	thunk += nh;

+	if(brk(hunk+nhunk) < 0)

+		sysfatal("out of memory");

 }

 void*

--- a/sys/src/cmd/cc/compat.h

+++ b/sys/src/cmd/cc/compat.h

@@ -23,12 +23,11 @@

 EXTERN	int	mydup(int, int);

 EXTERN	int	myfork(void);

 EXTERN	int	mypipe(int*);

-EXTERN	void*	mysbrk(ulong);

 EXTERN	void	gethunk(void);

 EXTERN	char*	hunk;

-EXTERN	uintptr	nhunk;

+EXTERN	long	nhunk;

 EXTERN	uintptr	thunk;

 EXTERN	void*	alloc(long n);