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-rw-r--r--include/stc/forward.h20
-rw-r--r--misc/benchmarks/various/cspan_bench.c43
-rw-r--r--misc/examples/spans/submdspan.c8
3 files changed, 24 insertions, 47 deletions
diff --git a/include/stc/forward.h b/include/stc/forward.h
index 2372a618..2fbff034 100644
--- a/include/stc/forward.h
+++ b/include/stc/forward.h
@@ -41,13 +41,13 @@
// csview : non-null terminated string view
typedef const char csview_value;
-typedef struct csview {
- csview_value* buf;
+typedef struct csview {
+ csview_value* buf;
intptr_t size;
} csview;
-typedef union {
- csview_value* ref;
+typedef union {
+ csview_value* ref;
csview chr;
struct { csview chr; csview_value* end; } u8;
} csview_iter;
@@ -55,13 +55,13 @@ typedef union {
// crawstr : null-terminated string view
typedef csview_value crawstr_value;
-typedef struct crawstr {
- crawstr_value* str;
+typedef struct crawstr {
+ crawstr_value* str;
intptr_t size;
} crawstr;
-typedef union {
- crawstr_value* ref;
+typedef union {
+ crawstr_value* ref;
csview chr;
struct { csview chr; } u8; // [deprecated]
} crawstr_iter;
@@ -75,8 +75,8 @@ typedef union cstr {
struct { cstr_value* data; size_t size, ncap; } lon;
} cstr;
-typedef union {
- cstr_value* ref;
+typedef union {
+ cstr_value* ref;
csview chr;
struct { csview chr; } u8; // [deprecated]
} cstr_iter;
diff --git a/misc/benchmarks/various/cspan_bench.c b/misc/benchmarks/various/cspan_bench.c
index b5caca83..3b1c3132 100644
--- a/misc/benchmarks/various/cspan_bench.c
+++ b/misc/benchmarks/various/cspan_bench.c
@@ -1,3 +1,4 @@
+// ref: https://stackoverflow.com/questions/74382366/why-is-iterating-over-stdrangesviewsjoin-so-slow
#define NDEBUG
#include <stc/cspan.h>
#include <stdio.h>
@@ -11,6 +12,7 @@ enum {
ny = 64,
nz = 64
};
+// subspan 15x5x10:
int lx = 15, ly = 10, lz = 5;
int hx = 30, hy = 15, hz = 15;
@@ -20,27 +22,7 @@ double Vin[nx * ny * nz]; //, 1.23;
// define some slice indices for each dimension
-static void MDRanges_setup(intptr_t n)
-{
- double sum = 0;
- clock_t t = clock();
-
- for (intptr_t s = 0; s < n; ++s)
- {
- MD3 r_in = cspan_md(Vin, nx, ny, nz);
- MD3 r_out = cspan_md(Vout, nx, ny, nz);
-
- r_in = cspan_slice(MD3, &r_in, {lx, hx}, {ly, hy}, {lz, hz});
- r_out = cspan_slice(MD3, &r_out, {lx, hx}, {ly, hy}, {lz, hz});
- MD3_iter i = MD3_begin(&r_in); // can be iterated "flat".
- MD3_iter o = MD3_begin(&r_out);
- sum += Vin[s % nx];
- }
- t = clock() - t;
- printf("setup: %.1f ms, %f\n", 1000.0f * t / CLOCKS_PER_SEC, sum);
-}
-
-static void TraditionalForLoop(intptr_t n)
+static void Traditional_for_loop(intptr_t n)
{
clock_t t = clock();
double sum = 0;
@@ -57,7 +39,7 @@ static void TraditionalForLoop(intptr_t n)
}
}
t = clock() - t;
- printf("forloop: %.1f ms, %f\n", 1000.0f * t / CLOCKS_PER_SEC, sum);
+ printf("forloop : %.1f ms, %f\n", 1000.0f*t / CLOCKS_PER_SEC, sum);
}
static void MDRanges_nested_loop(intptr_t n)
@@ -67,8 +49,6 @@ static void MDRanges_nested_loop(intptr_t n)
MD3 r_out = cspan_md(Vout, nx, ny, nz);
r_in = cspan_slice(MD3, &r_in, {lx, hx}, {ly, hy}, {lz, hz});
r_out = cspan_slice(MD3, &r_out, {lx, hx}, {ly, hy}, {lz, hz});
-
- // C++23: for (auto [o, i] : std::views::zip(flat(r_out), flat(r_in))) { o = i; }
double sum = 0;
for (intptr_t s = 0; s < n; ++s) {
@@ -76,27 +56,25 @@ static void MDRanges_nested_loop(intptr_t n)
for (int y = 0; y < r_in.shape[1]; ++y) {
for (int z = 0; z < r_in.shape[2]; ++z)
{
- double d = *cspan_at(&r_in, x, y, z);
- *cspan_at(&r_out, x, y, z) += d;
+ double d = *cspan_at(&r_in, x,y,z);
+ *cspan_at(&r_out, x,y,z) += d;
sum += d;
}
}
}
}
t = clock() - t;
- printf("nested: %.1f ms, %f\n", 1000.0f * t / CLOCKS_PER_SEC, sum);
+ printf("nested : %.1f ms, %f\n", 1000.0f*t / CLOCKS_PER_SEC, sum);
}
static void MDRanges_loop_over_joined(intptr_t n)
{
+ clock_t t = clock();
MD3 r_in = cspan_md(Vin, nx, ny, nz);
MD3 r_out = cspan_md(Vout, nx, ny, nz);
r_in = cspan_slice(MD3, &r_in, {lx, hx}, {ly, hy}, {lz, hz});
r_out = cspan_slice(MD3, &r_out, {lx, hx}, {ly, hy}, {lz, hz});
-
- // C++23: for (auto [o, i] : std::views::zip(flat(r_out), flat(r_in))) { o = i; }
double sum = 0;
- clock_t t = clock();
for (intptr_t s = 0; s < n; ++s) {
MD3_iter i = MD3_begin(&r_in);
@@ -109,7 +87,7 @@ static void MDRanges_loop_over_joined(intptr_t n)
}
}
t = clock() - t;
- printf("joined: %.1f ms, %f\n", 1000.0f * t / CLOCKS_PER_SEC, sum);
+ printf("joined : %.1f ms, %f\n", 1000.0f*t / CLOCKS_PER_SEC, sum);
}
int main(void)
@@ -118,8 +96,7 @@ int main(void)
for (int i = 0; i < nx * ny * nz; ++i)
Vin[i] = i + 1.23;
- MDRanges_setup(n);
- TraditionalForLoop(n);
+ Traditional_for_loop(n);
MDRanges_nested_loop(n);
MDRanges_loop_over_joined(n);
}
diff --git a/misc/examples/spans/submdspan.c b/misc/examples/spans/submdspan.c
index fa0d5762..0752dfa1 100644
--- a/misc/examples/spans/submdspan.c
+++ b/misc/examples/spans/submdspan.c
@@ -3,11 +3,11 @@
#include <stdio.h>
#include <stc/cspan.h>
-using_cspan3(span, double); // define span, span2, span3
+using_cspan3(span, double); // shorthand for defining span, span2, span3
// Set all elements of a rank-2 mdspan to zero.
void zero_2d(span2 grid2d) {
- c_static_assert(cspan_rank(&grid2d) == 2);
+ (void)c_static_assert(cspan_rank(&grid2d) == 2);
for (int i = 0; i < grid2d.shape[0]; ++i) {
for (int j = 0; j < grid2d.shape[1]; ++j) {
*cspan_at(&grid2d, i,j) = 0;
@@ -16,7 +16,7 @@ void zero_2d(span2 grid2d) {
}
void zero_surface(span3 grid3d) {
- c_static_assert(cspan_rank(&grid3d) == 3);
+ (void)c_static_assert(cspan_rank(&grid3d) == 3);
zero_2d(cspan_slice(span2, &grid3d, {0}, {c_ALL}, {c_ALL}));
zero_2d(cspan_slice(span2, &grid3d, {c_ALL}, {0}, {c_ALL}));
zero_2d(cspan_slice(span2, &grid3d, {c_ALL}, {c_ALL}, {0}));
@@ -41,4 +41,4 @@ int main() {
}
puts("");
}
-} \ No newline at end of file
+}
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