rsz: direct compare in buffer-size comparator, drop make_tuple

Per review, the std::make_tuple temporaries add overhead and pull in
<tuple>; use a direct (cap, id) compare with cached bufferCin locals
instead, matching the explicit comparator style in Resizer.cc.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

Author: oharboe

src/rsz/src/Rebuffer.cc

@@ -1500,8 +1500,12 @@ void Rebuffer::init()
   }
 
   std::ranges::sort(buffer_sizes_, [=](BufferSize a, BufferSize b) {
-    return std::make_tuple(bufferCin(a.cell), a.cell->id())
-           < std::make_tuple(bufferCin(b.cell), b.cell->id());
+    const float cin_a = bufferCin(a.cell);
+    const float cin_b = bufferCin(b.cell);
+    if (cin_a != cin_b) {
+      return cin_a < cin_b;
+    }
+    return a.cell->id() < b.cell->id();
   });
 
   buffer_sizes_index_.clear();

src/rsz/src/RepairDesign.cc

@@ -14,7 +14,6 @@
 #include <optional>
 #include <set>
 #include <string>
-#include <tuple>
 #include <utility>
 #include <vector>
 
@@ -648,8 +647,12 @@ void RepairDesign::findBufferSizes()
                    resizer_->buffer_fast_sizes_.end()};
   std::ranges::sort(buffer_sizes_,
                     [=](sta::LibertyCell* a, sta::LibertyCell* b) {
-                      return std::make_tuple(bufferCin(a), a->id())
-                             < std::make_tuple(bufferCin(b), b->id());
+                      const float cin_a = bufferCin(a);
+                      const float cin_b = bufferCin(b);
+                      if (cin_a != cin_b) {
+                        return cin_a < cin_b;
+                      }
+                      return a->id() < b->id();
                     });
 }