From daa2a04fc9ca7abed3a58306b2627f84a89ddbbc Mon Sep 17 00:00:00 2001
From: FanDjango <51046875+FanDjango@users.noreply.github.com>
Date: Mon, 16 Nov 2020 21:56:05 +0100
Subject: [PATCH] Guards for large BLOCK_BUFFER_SIZE (>=128) (#20130)

Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>
---
 Marlin/src/inc/SanityCheck.h  |  2 ++
 Marlin/src/module/planner.cpp | 18 ++++++++----------
 Marlin/src/module/planner.h   |  6 +++++-
 3 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/Marlin/src/inc/SanityCheck.h b/Marlin/src/inc/SanityCheck.h
index 22930a7621..18506163f5 100644
--- a/Marlin/src/inc/SanityCheck.h
+++ b/Marlin/src/inc/SanityCheck.h
@@ -2759,6 +2759,8 @@ static_assert(   _ARR_TEST(3,0) && _ARR_TEST(3,1) && _ARR_TEST(3,2)
 
 #if !BLOCK_BUFFER_SIZE || !IS_POWER_OF_2(BLOCK_BUFFER_SIZE)
   #error "BLOCK_BUFFER_SIZE must be a power of 2."
+#elif BLOCK_BUFFER_SIZE > 64
+  #error "A very large BLOCK_BUFFER_SIZE is not needed and takes longer to drain the buffer on pause / cancel."
 #endif
 
 #if ENABLED(LED_CONTROL_MENU) && !IS_ULTIPANEL
diff --git a/Marlin/src/module/planner.cpp b/Marlin/src/module/planner.cpp
index 74535df1f9..147adb12e3 100644
--- a/Marlin/src/module/planner.cpp
+++ b/Marlin/src/module/planner.cpp
@@ -213,7 +213,7 @@ xyze_float_t Planner::previous_speed;
 float Planner::previous_nominal_speed_sqr;
 
 #if ENABLED(DISABLE_INACTIVE_EXTRUDER)
-  uint8_t Planner::g_uc_extruder_last_move[EXTRUDERS] = { 0 };
+  last_move_t Planner::g_uc_extruder_last_move[EXTRUDERS] = { 0 };
 #endif
 
 #ifdef XY_FREQUENCY_LIMIT
@@ -2037,22 +2037,20 @@ bool Planner::_populate_block(block_t * const block, bool split_move,
       #if ENABLED(DISABLE_INACTIVE_EXTRUDER) // Enable only the selected extruder
 
         LOOP_L_N(i, EXTRUDERS)
-          if (g_uc_extruder_last_move[i] > 0) g_uc_extruder_last_move[i]--;
-
-        #if HAS_DUPLICATION_MODE
-          if (extruder_duplication_enabled && extruder == 0) {
-            ENABLE_AXIS_E1();
-            g_uc_extruder_last_move[1] = (BLOCK_BUFFER_SIZE) * 2;
-          }
-        #endif
+          if (g_uc_extruder_last_move[i]) g_uc_extruder_last_move[i]--;
 
         #define ENABLE_ONE_E(N) do{ \
           if (extruder == N) { \
             ENABLE_AXIS_E##N(); \
             g_uc_extruder_last_move[N] = (BLOCK_BUFFER_SIZE) * 2; \
+            if ((N) == 0 && TERN0(HAS_DUPLICATION_MODE, extruder_duplication_enabled)) \
+              ENABLE_AXIS_E1(); \
           } \
-          else if (!g_uc_extruder_last_move[N]) \
+          else if (!g_uc_extruder_last_move[N]) { \
             DISABLE_AXIS_E##N(); \
+            if ((N) == 0 && TERN0(HAS_DUPLICATION_MODE, extruder_duplication_enabled)) \
+              DISABLE_AXIS_E1(); \
+          } \
         }while(0);
 
       #else
diff --git a/Marlin/src/module/planner.h b/Marlin/src/module/planner.h
index c4e11490b1..ac30938f2a 100644
--- a/Marlin/src/module/planner.h
+++ b/Marlin/src/module/planner.h
@@ -287,6 +287,10 @@ typedef struct {
   #endif
 } skew_factor_t;
 
+#if ENABLED(DISABLE_INACTIVE_EXTRUDER)
+  typedef IF<(BLOCK_BUFFER_SIZE > 64), uint16_t, uint8_t>::type last_move_t;
+#endif
+
 class Planner {
   public:
 
@@ -435,7 +439,7 @@ class Planner {
 
     #if ENABLED(DISABLE_INACTIVE_EXTRUDER)
        // Counters to manage disabling inactive extruders
-      static uint8_t g_uc_extruder_last_move[EXTRUDERS];
+      static last_move_t g_uc_extruder_last_move[EXTRUDERS];
     #endif
 
     #if HAS_WIRED_LCD