From db53bfdcff566b504b4104c5e717d96875a83a4b Mon Sep 17 00:00:00 2001
From: ZhuangYumin <zhuangyumin@sjtu.edu.cn>
Date: Tue, 31 Oct 2023 18:00:33 +0800
Subject: [PATCH] upd: trying to optmize

---
 data/CMakeLists.txt | 2 +-
 include/int2048.h   | 3 ++-
 src/CMakeLists.txt  | 2 +-
 src/int2048.cpp     | 8 ++++++--
 4 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/data/CMakeLists.txt b/data/CMakeLists.txt
index 2410c31..78cb5b2 100644
--- a/data/CMakeLists.txt
+++ b/data/CMakeLists.txt
@@ -1,6 +1,6 @@
 set(PROJECT_NAME ${CMAKE_PROJECT_NAME})
 set(CMAKE_CXX_STANDARD 17)
-set(CMAKE_CXX_FLAGS "-O2 -pg")
+set(CMAKE_CXX_FLAGS "-g")
 set(ENV{MAKEFLAGS} "-j16")
 include_directories(${PROJECT_SOURCE_DIR}/include)
 link_directories(${PROJECT_SOURCE_DIR}/src)
diff --git a/include/int2048.h b/include/int2048.h
index ce94023..92e0703 100644
--- a/include/int2048.h
+++ b/include/int2048.h
@@ -52,6 +52,7 @@ root= 6
   void RightMoveBy(int);
   void ProcessHalfBlock();
   void RestoreHalfBlock();
+
  public:
   int2048();
   int2048(long long);
@@ -86,7 +87,7 @@ root= 6
   int2048 &operator-=(const int2048 &);
   friend int2048 operator-(int2048, const int2048 &);
 
-  inline friend void UnsignedMultiply(int2048 &, const int2048 *, bool);
+  inline friend void UnsignedMultiply(int2048 &, const int2048 *, bool, int);
   int2048 &Multiply(const int2048 &);
   friend int2048 Multiply(int2048, const int2048 &);
 
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index ae73419..ef0718e 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1,5 +1,5 @@
 set(PROJECT_NAME ${CMAKE_PROJECT_NAME})
 set(CMAKE_CXX_STANDARD 17)
-set(CMAKE_CXX_FLAGS "-O2 -pg")
+set(CMAKE_CXX_FLAGS "-g")
 include_directories(${PROJECT_SOURCE_DIR}/include)
 add_library(int2048 STATIC int2048.cpp)
\ No newline at end of file
diff --git a/src/int2048.cpp b/src/int2048.cpp
index ea80abd..bfb93de 100644
--- a/src/int2048.cpp
+++ b/src/int2048.cpp
@@ -501,10 +501,14 @@ void int2048::NTTTransform(__int128_t *a, int NTT_blocks,
   }
 }
 inline void UnsignedMultiply(int2048 &A, const int2048 *pB,
-                             bool inverse = false) {
+                             bool inverse = false, int lenght_limit = 0) {
   if (&A == pB) throw "UnsignedMultiply: A and B are the same object";
   int blocks_of_A = ((A.num_length + int2048::kNum - 1) / int2048::kNum);
   int blocks_of_B = ((pB->num_length + int2048::kNum - 1) / int2048::kNum);
+  if (inverse) {
+    lenght_limit = std::min(lenght_limit, pB->num_length);
+    blocks_of_B = lenght_limit;
+  }
   int max_blocks = blocks_of_A + blocks_of_B;
   int NTT_blocks = 2;
   while (NTT_blocks < (max_blocks << 1)) NTT_blocks <<= 1;
@@ -704,7 +708,7 @@ inline void UnsignedDivide(int2048 &A, const int2048 *pB) {
     }
     assert(tmp_x.num_length % int2048::kNum == 0);
     assert(inverse_B.num_length % int2048::kNum == 0);
-    UnsignedMultiply(tmp_x, &inverse_B, true);
+    UnsignedMultiply(tmp_x, &inverse_B, true, inverse_B.num_length);
     for (int i = 0; i < tmp_x_error + inverseB_error; i++)
       tmp_x.RestoreHalfBlock();
     UnsignedMinus(inverse_two, &tmp_x, true);