/*
This file is part of drd, a thread error detector.
Copyright (C) 2006-2012 Bart Van Assche <bvanassche@acm.org>.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#ifndef __DRD_BITMAP_H
#define __DRD_BITMAP_H
#include "pub_drd_bitmap.h"
#include "pub_tool_basics.h"
#include "pub_tool_oset.h"
#include "pub_tool_libcbase.h"
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
#include "pub_tool_libcassert.h"
#endif
/* Bitmap representation. A bitmap is a data structure in which two bits are
* reserved per 32 bit address: one bit that indicates that the data at the
* specified address has been read, and one bit that indicates that the data
* has been written to.
*/
/* Client addresses are split into bitfields as follows:
* ------------------------------------------------------
* | Address MSB | Address LSB | Ignored bits |
* ------------------------------------------------------
* | Address MSB | UWord MSB | UWord LSB | Ignored bits |
* ------------------------------------------------------
*/
/* Address MSB / LSB split. */
/** Number of least significant address bits that are ignored. */
#define ADDR_IGNORED_BITS 0
#define ADDR_IGNORED_MASK ((1U << ADDR_IGNORED_BITS) - 1U)
#define ADDR_GRANULARITY (1U << ADDR_IGNORED_BITS)
/**
* Round argument a up to a multiple of (1 << ADDR_GRANULARITY), and next
* shift it right ADDR_GRANULARITY bits. The expression below is optimized
* for the case where a is a constant.
*/
#define SCALED_SIZE(a) \
(((((a) - 1U) | ADDR_IGNORED_MASK) + 1U) >> ADDR_IGNORED_BITS)
/**
* Number of bits assigned to the least significant component of an address.
*/
#define ADDR_LSB_BITS 12
/**
* Mask that has to be applied to an address of type Addr in order to
* compute the least significant part of an address split, after having
* shifted the address bits ADDR_GRANULARITY to the right.
*/
#define ADDR_LSB_MASK (((UWord)1 << ADDR_LSB_BITS) - 1U)
/** Compute least significant bits of an address of type Addr. */
static __inline__
UWord address_lsb(const Addr a)
{ return (a >> ADDR_IGNORED_BITS) & ADDR_LSB_MASK; }
/**
* Compute the first address for which address_lsb() is equal to
* address_lsb(a).
*/
static __inline__
Addr first_address_with_same_lsb(const Addr a)
{
return ((a | ADDR_IGNORED_MASK) ^ ADDR_IGNORED_MASK);
}
/**
* Compute the first address for which address_lsb() is greater than
* address_lsb(a).
*/
static __inline__
Addr first_address_with_higher_lsb(const Addr a)
{
return ((a | ADDR_IGNORED_MASK) + 1U);
}
/** Compute most significant bits of an address of type Addr. */
static __inline__
UWord address_msb(const Addr a)
{ return a >> (ADDR_LSB_BITS + ADDR_IGNORED_BITS); }
static __inline__
Addr first_address_with_higher_msb(const Addr a)
{
return ((a | ((ADDR_LSB_MASK << ADDR_IGNORED_BITS) | ADDR_IGNORED_MASK))
+ 1U);
}
/**
* Convert LSB and MSB back into an address.
*
* @note It is assumed that sizeof(Addr) == sizeof(UWord).
*/
static __inline__
Addr make_address(const UWord a1, const UWord a0)
{
return ((a1 << (ADDR_LSB_BITS + ADDR_IGNORED_BITS))
| (a0 << ADDR_IGNORED_BITS));
}
/** Number of bits that fit in a variable of type UWord. */
#define BITS_PER_UWORD (8U * sizeof(UWord))
/** Log2 of BITS_PER_UWORD. */
#if defined(VGA_x86) || defined(VGA_ppc32) || defined(VGA_arm) \
|| defined(VGA_mips32)
#define BITS_PER_BITS_PER_UWORD 5
#elif defined(VGA_amd64) || defined(VGA_ppc64) || defined(VGA_s390x)
#define BITS_PER_BITS_PER_UWORD 6
#else
#error Unknown platform.
#endif
/** Number of UWord's needed to store one bit per address LSB. */
#define BITMAP1_UWORD_COUNT (1U << (ADDR_LSB_BITS - BITS_PER_BITS_PER_UWORD))
/**
* Mask that has to be applied to an (Addr >> ADDR_IGNORED_BITS) expression
* in order to compute the least significant part of an UWord.
*/
#define UWORD_LSB_MASK (((UWord)1 << BITS_PER_BITS_PER_UWORD) - 1)
/**
* Compute index into bm0[] array.
*
* @param a Address shifted right ADDR_IGNORED_BITS bits.
*/
static __inline__
UWord uword_msb(const UWord a)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(a < (1U << ADDR_LSB_BITS));
#endif
return a >> BITS_PER_BITS_PER_UWORD;
}
/**
* Return the least significant bits.
*
* @param a Address shifted right ADDR_IGNORED_BITS bits.
*/
static __inline__
UWord uword_lsb(const UWord a)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(a < (1U << ADDR_LSB_BITS));
#endif
return a & UWORD_LSB_MASK;
}
/**
* Compute the highest address lower than a for which
* uword_lsb(address_lsb(a)) == 0.
*
* @param a Address.
*/
static __inline__
Addr first_address_with_same_uword_lsb(const Addr a)
{
return (a & (~UWORD_LSB_MASK << ADDR_IGNORED_BITS));
}
/**
* First address that will go in the UWord past the one 'a' goes in.
*
* @param a Address.
*/
static __inline__
Addr first_address_with_higher_uword_msb(const Addr a)
{
return ((a | ((UWORD_LSB_MASK << ADDR_IGNORED_BITS) | ADDR_IGNORED_MASK))
+ 1);
}
/* Local variables. */
static ULong s_bitmap2_creation_count;
/*********************************************************************/
/* Functions for manipulating a struct bitmap1. */
/*********************************************************************/
/* Lowest level, corresponding to the lowest ADDR_LSB_BITS of an address. */
struct bitmap1
{
UWord bm0_r[BITMAP1_UWORD_COUNT];
UWord bm0_w[BITMAP1_UWORD_COUNT];
};
static __inline__ UWord bm0_mask(const UWord a)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(address_msb(make_address(0, a)) == 0);
#endif
return ((UWord)1 << uword_lsb(a));
}
/** Set the bit corresponding to address a in bitmap bm0. */
static __inline__ void bm0_set(UWord* bm0, const UWord a)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(address_msb(make_address(0, a)) == 0);
#endif
bm0[uword_msb(a)] |= (UWord)1 << uword_lsb(a);
}
/**
* Set the bits corresponding to all of the addresses in range
* [ a << ADDR_IGNORED_BITS .. (a + size) << ADDR_IGNORED_BITS [
* in bitmap bm0.
*/
static __inline__ void bm0_set_range(UWord* bm0,
const UWord a, const SizeT size)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(size > 0);
tl_assert(address_msb(make_address(0, a)) == 0);
tl_assert(address_msb(make_address(0, a + size - 1)) == 0);
tl_assert(uword_msb(a) == uword_msb(a + size - 1));
#endif
bm0[uword_msb(a)]
|= (((UWord)1 << size) - 1) << uword_lsb(a);
}
/** Clear the bit corresponding to address a in bitmap bm0. */
static __inline__ void bm0_clear(UWord* bm0, const UWord a)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(address_msb(make_address(0, a)) == 0);
#endif
bm0[uword_msb(a)] &= ~((UWord)1 << uword_lsb(a));
}
/**
* Clear all of the addresses in range
* [ a << ADDR_IGNORED_BITS .. (a + size) << ADDR_IGNORED_BITS [
* in bitmap bm0.
*/
static __inline__ void bm0_clear_range(UWord* bm0,
const UWord a, const SizeT size)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(address_msb(make_address(0, a)) == 0);
tl_assert(size == 0 || address_msb(make_address(0, a + size - 1)) == 0);
tl_assert(size == 0 || uword_msb(a) == uword_msb(a + size - 1));
#endif
/*
* Note: although the expression below yields a correct result even if
* size == 0, do not touch bm0[] if size == 0 because this might otherwise
* cause an access of memory just past the end of the bm0[] array.
*/
if (size > 0)
{
bm0[uword_msb(a)]
&= ~((((UWord)1 << size) - 1) << uword_lsb(a));
}
}
/** Test whether the bit corresponding to address a is set in bitmap bm0. */
static __inline__ UWord bm0_is_set(const UWord* bm0, const UWord a)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(address_msb(make_address(0, a)) == 0);
#endif
return (bm0[uword_msb(a)] & ((UWord)1 << uword_lsb(a)));
}
/**
* Return true if a bit corresponding to any of the addresses in range
* [ a << ADDR_IGNORED_BITS .. (a + size) << ADDR_IGNORED_BITS [
* is set in bm0.
*/
static __inline__ UWord bm0_is_any_set(const UWord* bm0,
const Addr a, const SizeT size)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(size > 0);
tl_assert(address_msb(make_address(0, a)) == 0);
tl_assert(address_msb(make_address(0, a + size - 1)) == 0);
tl_assert(uword_msb(a) == uword_msb(a + size - 1));
#endif
return (bm0[uword_msb(a)] & ((((UWord)1 << size) - 1) << uword_lsb(a)));
}
/*********************************************************************/
/* Functions for manipulating a struct bitmap. */
/*********************************************************************/
/* Second level bitmap. */
struct bitmap2
{
Addr addr; ///< address_msb(...)
Bool recalc;
struct bitmap1 bm1;
};
static void bm2_clear(struct bitmap2* const bm2);
static __inline__
struct bitmap2* bm2_insert(struct bitmap* const bm, const UWord a1);
/**
* Rotate elements cache[0..n-1] such that the element at position n-1 is
* moved to position 0. This allows to speed up future cache lookups.
*/
static __inline__
void bm_cache_rotate(struct bm_cache_elem cache[], const int n)
{
#if 0
struct bm_cache_elem t;
tl_assert(2 <= n && n <= 8);
t = cache[0];
if (n > 1)
cache[0] = cache[1];
if (n > 2)
cache[1] = cache[2];
if (n > 3)
cache[2] = cache[3];
if (n > 4)
cache[3] = cache[4];
if (n > 5)
cache[4] = cache[5];
if (n > 6)
cache[5] = cache[6];
if (n > 7)
cache[6] = cache[7];
cache[n - 1] = t;
#endif
}
static __inline__
Bool bm_cache_lookup(struct bitmap* const bm, const UWord a1,
struct bitmap2** bm2)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
tl_assert(bm2);
#endif
#if DRD_BITMAP_N_CACHE_ELEM > 8
#error Please update the code below.
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 1
if (a1 == bm->cache[0].a1)
{
*bm2 = bm->cache[0].bm2;
return True;
}
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 2
if (a1 == bm->cache[1].a1)
{
*bm2 = bm->cache[1].bm2;
return True;
}
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 3
if (a1 == bm->cache[2].a1)
{
*bm2 = bm->cache[2].bm2;
bm_cache_rotate(bm->cache, 3);
return True;
}
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 4
if (a1 == bm->cache[3].a1)
{
*bm2 = bm->cache[3].bm2;
bm_cache_rotate(bm->cache, 4);
return True;
}
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 5
if (a1 == bm->cache[4].a1)
{
*bm2 = bm->cache[4].bm2;
bm_cache_rotate(bm->cache, 5);
return True;
}
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 6
if (a1 == bm->cache[5].a1)
{
*bm2 = bm->cache[5].bm2;
bm_cache_rotate(bm->cache, 6);
return True;
}
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 7
if (a1 == bm->cache[6].a1)
{
*bm2 = bm->cache[6].bm2;
bm_cache_rotate(bm->cache, 7);
return True;
}
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 8
if (a1 == bm->cache[7].a1)
{
*bm2 = bm->cache[7].bm2;
bm_cache_rotate(bm->cache, 8);
return True;
}
#endif
*bm2 = 0;
return False;
}
static __inline__
void bm_update_cache(struct bitmap* const bm,
const UWord a1,
struct bitmap2* const bm2)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
#if DRD_BITMAP_N_CACHE_ELEM > 8
#error Please update the code below.
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 8
bm->cache[7] = bm->cache[6];
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 7
bm->cache[6] = bm->cache[5];
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 6
bm->cache[5] = bm->cache[4];
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 5
bm->cache[4] = bm->cache[3];
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 4
bm->cache[3] = bm->cache[2];
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 3
bm->cache[2] = bm->cache[1];
#endif
#if DRD_BITMAP_N_CACHE_ELEM >= 2
bm->cache[1] = bm->cache[0];
#endif
bm->cache[0].a1 = a1;
bm->cache[0].bm2 = bm2;
}
/**
* Look up the address a1 in bitmap bm and return a pointer to a potentially
* shared second level bitmap. The bitmap where the returned pointer points
* at may not be modified by the caller.
*
* @param a1 client address shifted right by ADDR_LSB_BITS.
* @param bm bitmap pointer.
*/
static __inline__
const struct bitmap2* bm2_lookup(struct bitmap* const bm, const UWord a1)
{
struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
if (! bm_cache_lookup(bm, a1, &bm2))
{
bm2 = VG_(OSetGen_Lookup)(bm->oset, &a1);
bm_update_cache(bm, a1, bm2);
}
return bm2;
}
/**
* Look up the address a1 in bitmap bm and return a pointer to a second
* level bitmap that is not shared and hence may be modified.
*
* @param a1 client address shifted right by ADDR_LSB_BITS.
* @param bm bitmap pointer.
*/
static __inline__
struct bitmap2*
bm2_lookup_exclusive(struct bitmap* const bm, const UWord a1)
{
struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
if (! bm_cache_lookup(bm, a1, &bm2))
{
bm2 = VG_(OSetGen_Lookup)(bm->oset, &a1);
}
return bm2;
}
/** Clear the content of the second-level bitmap. */
static __inline__
void bm2_clear(struct bitmap2* const bm2)
{
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm2);
#endif
VG_(memset)(&bm2->bm1, 0, sizeof(bm2->bm1));
}
/**
* Insert an uninitialized second level bitmap for the address a1.
*
* @param bm bitmap pointer.
* @param a1 client address shifted right by ADDR_LSB_BITS.
*
* @note bitmap2::recalc isn't initialized here on purpose.
*/
static __inline__
struct bitmap2* bm2_insert(struct bitmap* const bm, const UWord a1)
{
struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
s_bitmap2_creation_count++;
bm2 = VG_(OSetGen_AllocNode)(bm->oset, sizeof(*bm2));
bm2->addr = a1;
VG_(OSetGen_Insert)(bm->oset, bm2);
bm_update_cache(bm, a1, bm2);
return bm2;
}
static __inline__
struct bitmap2* bm2_insert_copy(struct bitmap* const bm,
struct bitmap2* const bm2)
{
struct bitmap2* bm2_copy;
bm2_copy = bm2_insert(bm, bm2->addr);
VG_(memcpy)(&bm2_copy->bm1, &bm2->bm1, sizeof(bm2->bm1));
return bm2_copy;
}
/**
* Look up the address a1 in bitmap bm, and insert it if not found.
* The returned second level bitmap may not be modified.
*
* @param bm bitmap pointer.
* @param a1 client address shifted right by ADDR_LSB_BITS.
*/
static __inline__
struct bitmap2* bm2_lookup_or_insert(struct bitmap* const bm, const UWord a1)
{
struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
if (bm_cache_lookup(bm, a1, &bm2))
{
if (bm2 == 0)
{
bm2 = bm2_insert(bm, a1);
bm2_clear(bm2);
}
}
else
{
bm2 = VG_(OSetGen_Lookup)(bm->oset, &a1);
if (! bm2)
{
bm2 = bm2_insert(bm, a1);
bm2_clear(bm2);
}
bm_update_cache(bm, a1, bm2);
}
return bm2;
}
/**
* Look up the address a1 in bitmap bm, and insert it if not found.
* The returned second level bitmap may be modified.
*
* @param a1 client address shifted right by ADDR_LSB_BITS.
* @param bm bitmap pointer.
*/
static __inline__
struct bitmap2* bm2_lookup_or_insert_exclusive(struct bitmap* const bm,
const UWord a1)
{
return bm2_lookup_or_insert(bm, a1);
}
static __inline__
void bm2_remove(struct bitmap* const bm, const UWord a1)
{
struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
bm2 = VG_(OSetGen_Remove)(bm->oset, &a1);
VG_(OSetGen_FreeNode)(bm->oset, bm2);
bm_update_cache(bm, a1, NULL);
}
static __inline__
void bm_access_aligned_load(struct bitmap* const bm,
const Addr a1, const SizeT size)
{
struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
bm2 = bm2_lookup_or_insert_exclusive(bm, address_msb(a1));
bm0_set_range(bm2->bm1.bm0_r,
(a1 >> ADDR_IGNORED_BITS) & ADDR_LSB_MASK,
SCALED_SIZE(size));
}
static __inline__
void bm_access_aligned_store(struct bitmap* const bm,
const Addr a1, const SizeT size)
{
struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
bm2 = bm2_lookup_or_insert_exclusive(bm, address_msb(a1));
bm0_set_range(bm2->bm1.bm0_w,
(a1 >> ADDR_IGNORED_BITS) & ADDR_LSB_MASK,
SCALED_SIZE(size));
}
static __inline__
Bool bm_aligned_load_has_conflict_with(struct bitmap* const bm,
const Addr a, const SizeT size)
{
const struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
bm2 = bm2_lookup(bm, address_msb(a));
return (bm2
&& bm0_is_any_set(bm2->bm1.bm0_w,
address_lsb(a),
SCALED_SIZE(size)));
}
static __inline__
Bool bm_aligned_store_has_conflict_with(struct bitmap* const bm,
const Addr a, const SizeT size)
{
const struct bitmap2* bm2;
#ifdef ENABLE_DRD_CONSISTENCY_CHECKS
tl_assert(bm);
#endif
bm2 = bm2_lookup(bm, address_msb(a));
if (bm2)
{
if (bm0_is_any_set(bm2->bm1.bm0_r, address_lsb(a), SCALED_SIZE(size))
| bm0_is_any_set(bm2->bm1.bm0_w, address_lsb(a), SCALED_SIZE(size)))
{
return True;
}
}
return False;
}
#endif /* __DRD_BITMAP_H */