[SYCL] Improve efficiency of stream output of h_item for FPGA.

This is done by creating a loop in writeHItem and ItemToStr,
rather than calling the same function multiple times.
Because everything is inlined in the FPGA flow, the latter results in many
copies of each function in hardware, which costs significant
FPGA area.  In a loop, the function will be created once on the
FPGA, and invoked multiple times.

Signed-off-by: David Cashman <[email protected]>

Author: David Cashman

sycl/include/CL/sycl/detail/stream_impl.hpp

@@ -370,7 +370,6 @@ inline EnableIfFP<T, unsigned> ScalarToStr(const T &Val, char *Buf,
   T Neg = -Val;
   auto AbsVal = Val < 0 ? Neg : Val;
 
-
   if (Val < 0) {
     Buf[Offset++] = '-';
   } else if (Flags & ShowPos) {
@@ -615,10 +614,10 @@ template <int Dimensions>
 inline unsigned ItemToStr(char *Buf, const item<Dimensions, false> &Item) {
   unsigned Len = 0;
   Len += append(Buf, "item(");
-  Len += append(Buf + Len, "range: ");
-  Len += ArrayToStr(Buf + Len, Item.get_range());
-  Len += append(Buf + Len, ", id: ");
-  Len += ArrayToStr(Buf + Len, Item.get_id());
+  for (int I = 0; I < 2; ++I) {
+    Len += append(Buf + Len, I == 0 ? "range: " : ", id: ");
+    Len += ArrayToStr(Buf + Len, I == 0 ? Item.get_range() : Item.get_id());
+  }
   Buf[Len++] = ')';
   return Len;
 }
@@ -632,17 +631,18 @@ inline void writeHItem(stream_impl::OffsetAccessorType &OffsetAcc,
   char Buf[3 * MAX_ITEM_SIZE + 60];
   unsigned Len = 0;
   Len += append(Buf, "h_item(");
-  Len += append(Buf + Len, "\n  global ");
-  Len += ItemToStr(Buf + Len, HItem.get_global());
-  Len += append(Buf + Len, "\n  logical local ");
-  Len += ItemToStr(Buf + Len, HItem.get_logical_local());
-  Len += append(Buf + Len, "\n  physical local ");
-  Len += ItemToStr(Buf + Len, HItem.get_physical_local());
+  for (int I = 0; I < 3; ++I) {
+    Len += append(Buf + Len, I == 0 ? "\n  global "
+                                    : I == 1 ? "\n  logical local "
+                                             : "\n  physical local ");
+    Len += ItemToStr(Buf + Len, I == 0 ? HItem.get_global()
+                                       : I == 1 ? HItem.get_logical_local()
+                                                : HItem.get_physical_local());
+  }
   Len += append(Buf + Len, "\n)");
   write(OffsetAcc, Acc, Len, Buf);
 }
 
 } // namespace detail
 } // namespace sycl
 } // namespace cl
-