diff options
| author | Rasmus Villemoes <linux@rasmusvillemoes.dk> | 2015-02-10 11:12:21 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-03-25 15:04:57 +0100 |
| commit | bea2b592fd18eb8ffa3fc4ad380610632d03a38f (patch) | |
| tree | 82a139e42a1812111dacc5a23b8b5fcb39058396 | |
| parent | 7085a7401ba54e92bbb5aa24d6f428071e18e509 (diff) | |
lib/lz4: Pull out constant tables
There's no reason to allocate the dec{32,64}table on the stack; it
just wastes a bunch of instructions setting them up and, of course,
also consumes quite a bit of stack. Using size_t for such small
integers is a little excessive.
$ scripts/bloat-o-meter /tmp/built-in.o lib/built-in.o
add/remove: 2/2 grow/shrink: 2/0 up/down: 1304/-1548 (-244)
function old new delta
lz4_decompress_unknownoutputsize 55 718 +663
lz4_decompress 55 632 +577
dec64table - 32 +32
dec32table - 32 +32
lz4_uncompress 747 - -747
lz4_uncompress_unknownoutputsize 801 - -801
The now inlined lz4_uncompress functions used to have a stack
footprint of 176 bytes (according to -fstack-usage); their inlinees
have increased their stack use from 32 bytes to 48 and 80 bytes,
respectively.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | lib/lz4/lz4_decompress.c | 18 |
1 files changed, 7 insertions, 11 deletions
diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c index f0f5c5c3de12..26cc6029b280 100644 --- a/lib/lz4/lz4_decompress.c +++ b/lib/lz4/lz4_decompress.c @@ -47,6 +47,11 @@ #include "lz4defs.h" +static const int dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; +#if LZ4_ARCH64 +static const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3}; +#endif + static int lz4_uncompress(const char *source, char *dest, int osize) { const BYTE *ip = (const BYTE *) source; @@ -56,10 +61,6 @@ static int lz4_uncompress(const char *source, char *dest, int osize) BYTE *cpy; unsigned token; size_t length; - size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; -#if LZ4_ARCH64 - size_t dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3}; -#endif while (1) { @@ -116,7 +117,7 @@ static int lz4_uncompress(const char *source, char *dest, int osize) /* copy repeated sequence */ if (unlikely((op - ref) < STEPSIZE)) { #if LZ4_ARCH64 - size_t dec64 = dec64table[op - ref]; + int dec64 = dec64table[op - ref]; #else const int dec64 = 0; #endif @@ -177,11 +178,6 @@ static int lz4_uncompress_unknownoutputsize(const char *source, char *dest, BYTE * const oend = op + maxoutputsize; BYTE *cpy; - size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; -#if LZ4_ARCH64 - size_t dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3}; -#endif - /* Main Loop */ while (ip < iend) { @@ -249,7 +245,7 @@ static int lz4_uncompress_unknownoutputsize(const char *source, char *dest, /* copy repeated sequence */ if (unlikely((op - ref) < STEPSIZE)) { #if LZ4_ARCH64 - size_t dec64 = dec64table[op - ref]; + int dec64 = dec64table[op - ref]; #else const int dec64 = 0; #endif |