| Index: src/trusted/validator_ragel/decoding.h
|
| ===================================================================
|
| --- src/trusted/validator_ragel/decoding.h (revision 9911)
|
| +++ src/trusted/validator_ragel/decoding.h (working copy)
|
| @@ -12,7 +12,7 @@
|
| #ifndef NATIVE_CLIENT_SRC_TRUSTED_VALIDATOR_RAGEL_DECODING_H_
|
| #define NATIVE_CLIENT_SRC_TRUSTED_VALIDATOR_RAGEL_DECODING_H_
|
|
|
| -#include "native_client/src/trusted/validator_ragel/unreviewed/decoder.h"
|
| +#include "native_client/src/trusted/validator_ragel/decoder.h"
|
|
|
| #if NACL_WINDOWS
|
| # define FORCEINLINE __forceinline
|
| @@ -84,6 +84,62 @@
|
| return is4 >> 4;
|
| }
|
|
|
| +/*
|
| + * SignExtendXXBit is used to sign-extend XX-bit value to unsigned 64-bit value.
|
| + *
|
| + * To do that you need to pass unsigned value of smaller then 64-bit size
|
| + * to this function: it will be converted to signed value and then
|
| + * sign-extended to become 64-bit value.
|
| + *
|
| + * Smaller values can be obtained by restricting this value further (which is
|
| + * safe according to the C language specification: see 6.2.1.2 in C90 and
|
| + * 6.3.1.3.2 in C99 specification).
|
| + *
|
| + * Note that these operations are safe but slightly unusual: they come very
|
| + * close to the edge of what “well-behaved C program is not supposed to do”,
|
| + * but they stay on the “safe” side of this boundary. Specifically: this
|
| + * behavior triggers “implementation-defined behavior” (see 6.2.1.2 in C90
|
| + * specification and 6.3.1.3.3 in C99 specification) which sounds suspiciously
|
| + * similar to the dreaded “undefined behavior”, but in reality these two are
|
| + * quite different: any program which triggers “undefined behavior” is not a
|
| + * valid C program at all, but program which tirggers “implementation-defined
|
| + * behavior” is quite valid C program. What this program actually *does*
|
| + * depends on the specification of a given C compiler: each particular
|
| + * implementation must decide for itself what it'll do in this particular case
|
| + * and *stick* *to* *it*. If the implementation uses two's-complement negative
|
| + * numbers (and all the implementation which can compile this code *must*
|
| + * support two's-complement arythmetic—see 7.18.1.1 in C99 specification) then
|
| + * the easiest thing to do is to do what we need here—this is what all known
|
| + * compilers for all known platforms are actually doing.
|
| + */
|
| +static FORCEINLINE uint64_t SignExtend8Bit(int8_t value) {
|
| + return value;
|
| +}
|
| +
|
| +static FORCEINLINE uint64_t SignExtend16Bit(int16_t value) {
|
| + return value;
|
| +}
|
| +
|
| +static FORCEINLINE uint64_t SignExtend32Bit(int32_t value) {
|
| + return value;
|
| +}
|
| +
|
| +static FORCEINLINE uint64_t AnyFieldValue8bit(const uint8_t *start) {
|
| + return *start;
|
| +}
|
| +
|
| +static FORCEINLINE uint64_t AnyFieldValue16bit(const uint8_t *start) {
|
| + return (start[0] + 256U * start[1]);
|
| +}
|
| +
|
| +static FORCEINLINE uint64_t AnyFieldValue32bit(const uint8_t *start) {
|
| + return (start[0] + 256U * (start[1] + 256U * (start[2] + 256U * (start[3]))));
|
| +}
|
| +static FORCEINLINE uint64_t AnyFieldValue64bit(const uint8_t *start) {
|
| + return (*start + 256ULL * (start[1] + 256ULL * (start[2] + 256ULL *
|
| + (start[3] + 256ULL * (start[4] + 256ULL * (start[5] + 256ULL *
|
| + (start[6] + 256ULL * start[7])))))));
|
| +}
|
| static const uint8_t index_registers[] = {
|
| /* Note how REG_RIZ falls out of the pattern. */
|
| REG_RAX, REG_RCX, REG_RDX, REG_RBX,
|
|
|