2f859f80c2
Use TARGET_PAGE_SIZE and ~TARGET_PAGE_MASK instead.
"DumpState.page_size" has type "size_t", whereas TARGET_PAGE_SIZE has type
"int". TARGET_PAGE_MASK is of type "int" and has negative value. The patch
affects the implicit type conversions as follows:
- create_header32() and create_header64(): assigned to "block_size", which
has type "uint32_t". No change.
- get_next_page(): "block->target_start", "block->target_end" and "addr"
have type "hwaddr" (uint64_t).
Before the patch,
- if "size_t" was "uint64_t", then no additional conversion was done as
part of the usual arithmetic conversions,
- If "size_t" was "uint32_t", then it was widened to uint64_t as part of
the usual arithmetic conversions,
for the remainder and addition operators.
After the patch,
- "~TARGET_PAGE_MASK" expands to ~~((1 << TARGET_PAGE_BITS) - 1). It
has type "int" and positive value (only least significant bits set).
That's converted (widened) to "uint64_t" for the bit-ands. No visible
change.
- The same holds for the (addr + TARGET_PAGE_SIZE) addition.
- write_dump_pages():
- TARGET_PAGE_SIZE passed as argument to a bunch of functions that all
have prototypes. No change.
- When incrementing "offset_data" (of type "off_t"): given that we never
build for ILP32_OFF32 (see "-D_FILE_OFFSET_BITS=64" in configure),
"off_t" is always "int64_t", and we only need to consider:
- ILP32_OFFBIG: "size_t" is "uint32_t".
- before: int64_t += uint32_t. Page size converted to int64_t for
the addition.
- after: int64_t += int32_t. No change.
- LP64_OFF64: "size_t" is "uint64_t".
- before: int64_t += uint64_t. Offset converted to uint64_t for the
addition, then the uint64_t result is converted to int64_t for
storage.
- after: int64_t += int32_t. Same as the ILP32_OFFBIG/after case.
No visible change.
- (size_out < s->page_size) comparisons, and (size_out = s->page_size)
assignment:
- before: "size_out" is of type "size_t", no implicit conversion for
either operator.
- after: TARGET_PAGE_SIZE (of type "int" and positive value) is
converted to "size_t" (for the relop because the latter is
one of "uint32_t" and "uint64_t"). No visible change.
- dump_init():
- DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), s->page_size): The
innermost "DumpState.max_mapnr" field has type uint64_t, which
propagates through all implicit conversions at hand:
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
regardless of the page size macro argument's type. In the outer macro
replacement, the page size is converted from uint32_t and int32_t
alike to uint64_t.
- (tmp * s->page_size) multiplication: "tmp" has size "uint64_t"; the
RHS is converted to that type from uint32_t and int32_t just the same
if it's not uint64_t to begin with.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Read the documentation in qemu-doc.html or on http://wiki.qemu-project.org - QEMU team