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-rw-r--r--gen/bits/intconf.c52
-rw-r--r--gen/bits/intconf.h117
2 files changed, 168 insertions, 1 deletions
diff --git a/gen/bits/intconf.c b/gen/bits/intconf.c
index 7e48fce..5a52d12 100644
--- a/gen/bits/intconf.c
+++ b/gen/bits/intconf.c
@@ -21,7 +21,18 @@
+/**
+ * Used to determine the signness of `char`.
+ */
volatile char nul = 0;
+
+/**
+ * Used to determine the signness of `wchar_t`.
+ *
+ * Note that `wchar_t` is set implicitly by the
+ * help of the compiler so that our libc does
+ * not taint the result.
+ */
volatile typeof(L'\0') wnul = 0;
@@ -35,6 +46,15 @@ volatile typeof(L'\0') wnul = 0;
*/
+/**
+ * Measure the performance of a intrinsic integer type,
+ * and if it is faster than the previous candidate (or
+ * is the first candidate,) store it as the, yet, most
+ * performant candidate.
+ *
+ * @param VAR A volatile register variable of the
+ * type that shall be tested.
+ */
#define FAST_TEST(VAR) \
n = 0, *VAR##p = 0; \
if (clock_gettime(CLOCK_THREAD_CPUTIME_ID, &start)) \
@@ -65,10 +85,26 @@ volatile typeof(L'\0') wnul = 0;
last = this
+/**
+ * Determine whether the performance of `typeof(VAR)` should be determined,
+ * when finding the most performant, compatiable intrinsic type of a `int_fastN_t`.
+ *
+ * @param VAR An variable of the type (or the type itself) that is a candidate.
+ * @return Determine whether the type shall be tested.
+ */
#define TEST(VAR) (this = 8 * (int)sizeof(VAR), ((this >= bits) && (this > last)))
+
#if defined(__GNUC__)
__attribute__((optimize("-O0")))
#endif
+/**
+ * Find the (in general) fastest intrinsic integer type,
+ * that has at least a specified number of bits.
+ *
+ * @param bits The minimum number of bits the type may have.
+ * @return The number of bits the most performance
+ * compatible integer type has.
+ */
static int fast(int bits)
{
int last = 0, this = 0, best = 0, n, m;
@@ -103,11 +139,26 @@ static int fast(int bits)
#undef TEST
+/**
+ * @param argc The number of command line arguments, should
+ * be either 1 (print integer width information)
+ * or 2 (otherwise).
+ * @param argv Command line arguments, if `argc == 2`, `argv[2]`
+ * is interpreted as follows:
+ * - "fast8" Print the number of bits in `int_fast8_t` and `uint_fast8_t`.
+ * - "fast16" Print the number of bits in `int_fast16_t` and `uint_fast16_t`.
+ * - "fast32" Print the number of bits in `int_fast32_t` and `uint_fast32_t`.
+ * - "fast64" Print the number of bits in `int_fast64_t` and `uint_fast64_t`.
+ * - "char-signed" Print 1 if `char` is signed, and `0` if it is unsigned.
+ * - "wchar-signed" Print 1 if `wchar_t` is signed, and `0` if it is unsigned.
+ * @return 0 on success, 1 on error (including printing error.)
+ */
int main(int argc, char* argv[])
{
int r = 0;
if (argc < 2)
{
+ /* Print the number of bits in the intrinsic integers types. */
r |= printf("CHAR_BIT %zu\n", 8 * sizeof(char));
r |= printf("SHORT_BIT %zu\n", 8 * sizeof(short int));
r |= printf("INT_BIT %zu\n", 8 * sizeof(int));
@@ -116,6 +167,7 @@ int main(int argc, char* argv[])
r |= printf("PTR_BIT %zu\n", 8 * sizeof(void*));
r |= printf("WCHAR_BIT %zu\n", 8 * sizeof(L'\0'));
+ /* Print the intrinsic type for specific numbers of bits. */
r |= printf("INT%zu %s\n", 8 * sizeof(char), "char");
r |= printf("INT%zu %s\n", 8 * sizeof(short int), "short int");
r |= printf("INT%zu %s\n", 8 * sizeof(int), "int");
diff --git a/gen/bits/intconf.h b/gen/bits/intconf.h
index 128b0ba..69ea473 100644
--- a/gen/bits/intconf.h
+++ b/gen/bits/intconf.h
@@ -24,41 +24,156 @@
//>FAST32=$(bin/gen/bits/intconf fast32)
//>FAST64=$(bin/gen/bits/intconf fast64)
-#define __MAX_TO_MIN(max) (-(max) - 1)
+
+/**
+ * Converts an integer's maximum value to
+ * its [the integer's] minimum value.
+ */
+#define __MAX_TO_MIN(max) (-(max) - 1) /* TODO compiler-flag-dependent */
+
+/* TODO compiler-flag-dependent */
#if //(bin/gen/bits/intconf char-signed)
+/**
+ * Set if and only if `char` is signed by default.
+ */
# define __CHAR_SIGNED
+
+/**
+ * The default signness-modifiers for `char`.
+ */
# define __CHAR_SIGNNESS signed
#else
# define __CHAR_SIGNNESS unsigned
#endif
+
#if //(bin/gen/bits/intconf wchar-signed)
+/**
+ * Set if and only if `wchar_t` is signed by default.
+ */
# define __WCHAR_SIGNED
+
+/**
+ * The default signness-modifiers for `wchar_t`.
+ */
# define __WCHAR_SIGNNESS signed
#else
# define __WCHAR_SIGNNESS unsigned
#endif
+
+/**
+ * The number of bits in `char`.
+ * (8 is mandatates, but I did it thus way for uniformity.)
+ */
#define __CHAR_BIT //(bin/gen/bits/intconf | grep ^CHAR_BIT | sed "s/^[^ ]* //")
+
+/**
+ * The number of bits in `short int`.
+ */
#define __SHORT_BIT //(bin/gen/bits/intconf | grep ^SHORT_BIT | sed "s/^[^ ]* //")
+
+/**
+ * The number of bits in `int`.
+ */
#define __INT_BIT //(bin/gen/bits/intconf | grep ^INT_BIT | sed "s/^[^ ]* //")
+
+/**
+ * The number of bits in `long int`.
+ */
#define __LONG_BIT //(bin/gen/bits/intconf | grep ^LONG_BIT | sed "s/^[^ ]* //")
+
+/**
+ * The number of bits in `long long int`.
+ */
#define __LONG_LONG_BIT //(bin/gen/bits/intconf | grep ^LONG_LONG_BIT | sed "s/^[^ ]* //")
+
+/**
+ * The number of bits in `void*`.
+ */
#define __PTR_BIT //(bin/gen/bits/intconf | grep ^PTR_BIT | sed "s/^[^ ]* //")
+
+/**
+ * The number of bits in `wchar`.
+ */
#define __WCHAR_BIT //(bin/gen/bits/intconf | grep ^WCHAR_BIT | sed "s/^[^ ]* //")
+
+/**
+ * The underlaying intrinsic type for `int8_t` or `uint8_t`.
+ */
#define __INT8 //(bin/gen/bits/intconf | grep ^INT8 | sed "s/^[^ ]* //" | sed 1q)
+
+/**
+ * The underlaying intrinsic type for `int16_t` or `uint16_t`.
+ */
#define __INT16 //(bin/gen/bits/intconf | grep ^INT16 | sed "s/^[^ ]* //" | sed 1q)
+
+/**
+ * The underlaying intrinsic type for `int32_t` or `uint32_t`.
+ */
#define __INT32 //(bin/gen/bits/intconf | grep ^INT32 | sed "s/^[^ ]* //" | sed 1q)
+
+/**
+ * The underlaying intrinsic type for `int64_t` or `uint64_t`.
+ */
#define __INT64 //(bin/gen/bits/intconf | grep ^INT64 | sed "s/^[^ ]* //" | sed 1q)
+
+/**
+ * The underlaying intrinsic type for `int8_t` or `uint8_t`.
+ */
#define __INT_FAST8 __INT//{FAST8}
+
+/**
+ * The underlaying intrinsic type for `int16_t` or `uint16_t`.
+ */
#define __INT_FAST16 __INT//{FAST16}
+
+/**
+ * The underlaying intrinsic type for `int32_t` or `uint32_t`.
+ */
#define __INT_FAST32 __INT//{FAST32}
+
+/**
+ * The underlaying intrinsic type for `int64_t` or `uint64_t`.
+ */
#define __INT_FAST64 __INT//{FAST64}
+
+/**
+ * The maximum value of `int_fast8_t`.
+ */
#define __INT_FAST8_MAX INT//{FAST8}_MAX
+
+/**
+ * The maximum value of `int_fast16_t`.
+ */
#define __INT_FAST16_MAX INT//{FAST16}_MAX
+
+/**
+ * The maximum value of `int_fast32_t`.
+ */
#define __INT_FAST32_MAX INT//{FAST32}_MAX
+
+/**
+ * The maximum value of `int_fast64_t`.
+ */
#define __INT_FAST64_MAX INT//{FAST64}_MAX
+
+/**
+ * The maximum value of `uint_fast8_t`.
+ */
#define __UINT_FAST8_MAX UINT//{FAST8}_MAX
+
+/**
+ * The maximum value of `uint_fast16_t`.
+ */
#define __UINT_FAST16_MAX UINT//{FAST16}_MAX
+
+/**
+ * The maximum value of `uint_fast32_t`.
+ */
#define __UINT_FAST32_MAX UINT//{FAST32}_MAX
+
+/**
+ * The maximum value of `uint_fast64_t`.
+ */
#define __UINT_FAST64_MAX UINT//{FAST64}_MAX
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-10-22 07:39:35 +0000