1 files changed, 158 insertions, 0 deletions
diff --git a/Carpet/CarpetLib/src/cacheinfo.hh b/Carpet/CarpetLib/src/cacheinfo.hh
new file mode 100644
index 000000000..14b464a86
--- /dev/null
+++ b/Carpet/CarpetLib/src/cacheinfo.hh
@@ -0,0 +1,158 @@
+#ifndef CACHEINFO_HH
+#define CACHEINFO_HH
+
+#include <cctk.h>
+
+#include <limits>
+
+#include "bbox.hh"
+#include "defs.hh"
+#include "vect.hh"
+
+
+
+static ptrdiff_t div_down (ptrdiff_t const x, ptrdiff_t const align)
+  CCTK_ATTRIBUTE_UNUSED;
+static ptrdiff_t div_down (ptrdiff_t const x, ptrdiff_t const align)
+{
+  assert (x >= 0);
+  assert (align > 0);
+  return x / align;
+}
+
+static ptrdiff_t div_up (ptrdiff_t const x, ptrdiff_t const align)
+  CCTK_ATTRIBUTE_UNUSED;
+static ptrdiff_t div_up (ptrdiff_t const x, ptrdiff_t const align)
+{
+  assert (x >= 0);
+  assert (align > 0);
+  return (x + align - 1) / align;
+}
+
+static ptrdiff_t align_down (ptrdiff_t const x, ptrdiff_t const align)
+  CCTK_ATTRIBUTE_UNUSED;
+static ptrdiff_t align_down (ptrdiff_t const x, ptrdiff_t const align)
+{
+  assert (x >= 0);
+  assert (align > 0);
+  return div_down(x, align) * align;
+}
+
+static ptrdiff_t align_up (ptrdiff_t const x, ptrdiff_t const align)
+  CCTK_ATTRIBUTE_UNUSED;
+static ptrdiff_t align_up (ptrdiff_t const x, ptrdiff_t const align)
+{
+  assert (x >= 0);
+  assert (align > 0);
+  return div_up(x, align) * align;
+}
+
+static ptrdiff_t next_power_of_2 (ptrdiff_t const x)
+  CCTK_ATTRIBUTE_UNUSED;
+static ptrdiff_t next_power_of_2 (ptrdiff_t const x)
+{
+  assert (x > 0);
+  ptrdiff_t res = 1;
+  while (res < x) {
+    res *= 2;
+    assert (res > 0);           // try to catch overflows
+  }
+  return res;
+}
+
+static ptrdiff_t previous_power_of_2 (ptrdiff_t const x)
+  CCTK_ATTRIBUTE_UNUSED;
+static ptrdiff_t previous_power_of_2 (ptrdiff_t const x)
+{
+  return next_power_of_2(x/2+1);
+}
+
+static bool is_power_of_2 (ptrdiff_t const x)
+  CCTK_ATTRIBUTE_UNUSED;
+static bool is_power_of_2 (ptrdiff_t const x)
+{
+  return x == next_power_of_2(x);
+}
+
+#if 0
+static ptrdiff_t lcm (ptrdiff_t const x, ptrdiff_t const y)
+  CCTK_ATTRIBUTE_UNUSED;
+static ptrdiff_t lcm (ptrdiff_t const x, ptrdiff_t const y)
+{
+  assert (x > 0 && y > 0);
+  ptrdiff_t z = x;
+  // TODO: improve LCM algorithm
+  while (z % y != 0) z += x;
+  assert (z % x == 0 && z % y == 0);
+  return z;
+}
+#endif
+
+
+
+class cacheinfo_t {
+  ptrdiff_t m_size;                // bytes
+  ptrdiff_t m_linesize;            // bytes (pagesize for TLBs)
+  ptrdiff_t m_associativity;
+public:
+  bool invariant () const
+  {
+    return
+      is_power_of_2(m_size) and
+      is_power_of_2(m_linesize) and
+      is_power_of_2(m_associativity) and
+      m_size % (m_linesize * m_associativity) == 0;
+  }
+  cacheinfo_t (ptrdiff_t const a_size,
+               ptrdiff_t const a_linesize,
+               ptrdiff_t const a_associativity)
+    : m_size (a_size),
+      m_linesize (a_linesize),
+      m_associativity (a_associativity)
+  {
+    assert (invariant());
+  }
+  cacheinfo_t (ptrdiff_t const a_linesize)
+    : m_size (previous_power_of_2(numeric_limits<ptrdiff_t>::max())),
+      m_linesize (a_linesize),
+      m_associativity (1)
+  {
+    assert (invariant());
+  }
+  // size in bytes
+  ptrdiff_t size() const
+  {
+    return m_size;
+  }
+  // line size in bytes
+  ptrdiff_t linesize() const
+  {
+    return m_linesize;
+  }
+  // associativity
+  ptrdiff_t associativity() const
+  {
+    return m_associativity;
+  }
+  // number of cache elements
+  ptrdiff_t num_elements() const
+  {
+    return size() / (linesize() * associativity());
+  }
+  // stride (between main memory locations that use the same cache
+  // element) in bytes
+  ptrdiff_t stride() const
+  {
+    return num_elements() * linesize();
+  }
+};
+
+
+
+// These routines are apparently not pure -- don't know why
+template<int D>
+vect<int,D> pad_shape (bbox<int,D> const& extent) /*CCTK_ATTRIBUTE_PURE*/;
+template<int D>
+vect<int,D> pad_shape (vect<int,D> const& shape) /*CCTK_ATTRIBUTE_PURE*/;
+
+#endif  // CACHEINFO_HH