[Decompilation] [th01] Pellets: Manager class constructor

Note how Turbo C++ auto-generates that call to `operator new`, which
you don't see in the decompilation anymore. So yeah, as soon as you add
a constructor, Turbo C++ enforces heap allocation for any instance of
that class, even function-local ones that would otherwise be
stack-allocated.

That's where the bad reputation of C++ comes from, I guess?

Part of P0102, funded by Yanga.

Makefile.mak

@@ -59,7 +59,7 @@ bin\th01\op.exe: bin\piloadc.obj bin\th01\op.obj th01\op_01.cpp th01\op_02.c th0
 $**
 |
 
-bin\th01\reiiden.exe: bin\piloadc.obj bin\th01\reiiden.obj th01\main_01.cpp th01\main_01_.cpp th01\main_02.c th01\main_03.c th01\main_04.c th01\main_05.c th01\main_06.cpp th01\main_07.cpp th01\main_08.cpp th01\main_09.cpp th01\main_12.c th01\main_13.cpp th01\main_13_.cpp th01\main_14.cpp th01\main_16.c th01\main_19.cpp th01\main_25.cpp th01\main_27.cpp th01\main_38.cpp th01\main_38_.cpp
+bin\th01\reiiden.exe: bin\piloadc.obj bin\th01\reiiden.obj th01\main_01.cpp th01\main_01_.cpp th01\main_02.c th01\main_03.c th01\main_04.c th01\main_05.c th01\main_06.cpp th01\main_07.cpp th01\main_08.cpp th01\main_09.cpp th01\main_12.c th01\main_13.cpp th01\main_13_.cpp th01\main_14.cpp th01\main_16.c th01\main_19.cpp th01\main_25.cpp th01\main_27.cpp th01\main_38.cpp
 	$(CC) $(CFLAGS) -ml -3 -DGAME=1 -DBINARY='M' -nbin\th01\ -eREIIDEN.EXE @&&|
 $**
 |

Research/Borland C++ decompilation.md

@@ -269,6 +269,50 @@ Examples:
   **Certainty**: Maybe Borland (not Turbo) C++ has an optimization option
   against it?
 
+### Boilerplate for constructors defined outside the class declaration
+
+```c++
+struct MyClass {
+  // Members…
+
+  MyClass();
+};
+
+MyClass::MyClass() {
+  // Initialization…
+}
+```
+
+Resulting ASM:
+
+```asm
+; MyClass::MyClass(MyClass* this)
+; Exact instructions differ depending on the memory model. Model-independent
+; ASM instructions are in UPPERCASE.
+@MyClass@$bctr$qv proc
+  PUSH  BP
+  MOV   BP, SP
+  ; (saving SI and DI, if used in constructor code)
+  ; (if this, 0)
+  JNZ   @@ctor_code
+  PUSH  sizeof(MyClass)
+  CALL  @$bnew$qui      ; operator new(uint)
+  POP   CX
+  ; (this = value_returned_from_new)
+  ; (if this)
+  JZ    @@ret
+
+@@ctor_code:
+  ; Initialization…
+
+@@ret:
+  ; (retval = this)
+  ; (restoring DI and SI, if used in constructor code)
+  POP   BP
+  RET
+@MyClass@$bctr$qv endp
+```
+
 ## Limits of decompilability
 
 ### `MOV BX, SP`-style functions, or others with no standard stack frame

th01/main/bullet/pellet.cpp

@@ -1,12 +1,3 @@
-#include "th01/math/subpixel.hpp"
-#include "th01/math/vector.hpp"
-#include "th01/main/vars.hpp"
-#include "th01/main/bullet/pellet.hpp"
-#include "th01/main/playfld.hpp"
-#include "th01/main/player/orb.hpp"
-#include "th01/main/player/player.hpp"
-#include "th01/main/player/shots.hpp"
-
 /// Constants
 /// ---------
 // Can't declare these as `static const` variables, because that would break
@@ -25,6 +16,24 @@ static const unsigned int PELLET_DESTROY_SCORE = 10;
 pellet_t near *pellet_cur;
 /// -------
 
+CPellets::CPellets(void)
+{
+	int i;
+
+	#define p pellet_cur
+	p = iteration_start();
+	for(i = 0; i < PELLET_COUNT; i++, p++) {
+		p->moving = false;
+		p->not_rendered = false;
+	}
+	#undef p
+
+	alive_count = 0;
+	for(i = 0; i < sizeof(unknown_zero) / sizeof(unknown_zero[0]); i++) {
+		unknown_zero[i] = 0;
+	}
+}
+
 void vector2_to_player_from(
 	int x, int y, int &ret_x, int &ret_y, int length, unsigned char plus_angle
 )

th01/main/bullet/pellet.hpp

@@ -168,6 +168,8 @@ protected:
 	bool16 visible_after_hittests_for_cur(int pellet_left, int pellet_top);
 
 public:
+	CPellets(void);
+
 	// Spawns a number of bullets according to the given [pattern], with their
 	// corresponding velocities, at (left, top). [speed_base] is tuned
 	// according to the currently played difficulty and the resident

th01/main/player/shots.cpp

@@ -1,11 +1,3 @@
-#include "th01/snd/mdrv2.h"
-#include "th01/formats/ptn.hpp"
-#include "th01/hardware/egc.h"
-#include "th01/main/playfld.hpp"
-#include "th01/main/player/player.hpp"
-#include "th01/main/player/orb.hpp"
-#include "th01/main/player/shots.hpp"
-
 static const int SHOT_SPRITE_MARGIN = 2;
 static const int SHOT_DECAY_FRAMES = 7;
 

th01/main_38.cpp

@@ -1,15 +1,26 @@
 /* ReC98
  * -----
- * 1st part of code segment #38 of TH01's REIIDEN.EXE
+ * Code segment #38 of TH01's REIIDEN.EXE
  */
 
 #pragma option -Z
 
 extern "C" {
-#include "platform.h"
+#include "th01/th01.h"
-#include "pc98.h"
+#include "th01/ranks.h"
-#include "planar.h"
+#include "th01/snd/mdrv2.h"
+#include "th01/formats/ptn.hpp"
+#include "th01/hardware/egc.h"
 #include "th01/math/subpixel.hpp"
+#include "th01/math/vector.hpp"
+#include "th01/main/vars.hpp"
+#include "th01/main/playfld.hpp"
+#include "th01/main/player/player.hpp"
+#include "th01/main/player/orb.hpp"
+#include "th01/main/bullet/pellet.hpp"
+#include "th01/main/player/shots.hpp"
 
 #include "th01/main/player/shots.cpp"
+#include "th01/main/bullet/pellet.cpp"
+
 }

th01/main_38_.cpp

@@ -1,15 +0,0 @@
-/* ReC98
- * -----
- * 2nd part of code segment #38 of TH01's REIIDEN.EXE
- */
-
-#pragma codeseg main_38__TEXT main_38
-#pragma option -Z
-
-extern "C" {
-#include "th01/th01.h"
-#include "th01/ranks.h"
-
-#include "th01/main/bullet/pellet.cpp"
-
-}

th01_reiiden.asm

@@ -73,7 +73,7 @@ main_13 group main_13_TEXT, main_13__TEXT
 main_19 group main_19_TEXT, main_19__TEXT
 main_25 group main_25_TEXT, main_25__TEXT
 main_27 group main_27_TEXT, main_27__TEXT
-main_38 group main_38_TEXT, main_38__TEXT, main_38___TEXT
+main_38 group main_38_TEXT, main_38__TEXT
 
 ; ===========================================================================
 
@@ -4483,7 +4483,7 @@ word_E309	dw	4,     9,   0Eh,   13h
 sub_E319	proc far
 		push	bp
 		mov	bp, sp
-		call	sub_30047 c, offset _Pellets, ds
+		call	@CPellets@$bctr$qv c, offset _Pellets, ds
 		mov	_Shots.SHOT_unknown[0 * word], 50h
 		mov	_Shots.SHOT_unknown[1 * word], 60h
 		mov	_Shots.SHOT_unknown[2 * word], 70h
@@ -53930,90 +53930,22 @@ main_37_TEXT	ends
 
 ; Segment type:	Pure code
 main_38_TEXT	segment	byte public 'CODE' use16
-main_38_TEXT	ends
-
-main_38__TEXT	segment	byte public 'CODE' use16
-		assume cs:main_38
-		;org 4
-		assume es:nothing, ss:nothing, ds:_DATA, fs:nothing, gs:nothing
-
 	extern @CShots@add$qii:proc
 	extern @CShots@unput_and_reset_all$qv:proc
 	extern @CShots@unput_update_render$qv:proc
 	extern @CShots@hittest_pellet$qii:proc
 	extern @CShots@hittest_boss$qiiii:proc
-
+	extern @CPellets@$bctr$qv:proc
-; =============== S U B	R O U T	I N E =======================================
-
-; Attributes: bp-based frame
-
-sub_30047	proc far
-
-@@CPellets		= dword	ptr  6
-
-		push	bp
-		mov	bp, sp
-		push	si
-		cmp	[bp+@@CPellets], 0
-		jnz	short loc_30065
-		push	size CPellets
-		call	@$bnew$qui	; operator new(uint)
-		pop	cx
-		mov	word ptr [bp+@@CPellets+2], dx
-		mov	word ptr [bp+@@CPellets], ax
-		or	ax, dx
-		jz	short loc_300AA
-
-loc_30065:
-		mov	ax, word ptr [bp+@@CPellets]
-		mov	_pellet_cur, ax
-		xor	si, si
-		jmp	short loc_30081
-; ---------------------------------------------------------------------------
-
-loc_3006F:
-		mov	bx, _pellet_cur
-		mov	byte ptr [bx], 0
-		mov	word ptr [bx+18h], 0
-		inc	si
-		add	_pellet_cur, size pellet_t
-
-loc_30081:
-		cmp	si, PELLET_COUNT
-		jl	short loc_3006F
-		les	bx, [bp+@@CPellets]
-		mov	es:[bx+CPellets.PELLET_alive_count], 0
-		xor	si, si
-		jmp	short loc_300A5
-; ---------------------------------------------------------------------------
-
-loc_30094:
-		mov	ax, si
-		add	ax, ax
-		les	bx, [bp+@@CPellets]
-		add	bx, ax
-		mov	es:[bx+PELLET_unknown_zero], 0
-		inc	si
-
-loc_300A5:
-		cmp	si, 10
-		jl	short loc_30094
-
-loc_300AA:
-		mov	dx, word ptr [bp+@@CPellets+2]
-		mov	ax, word ptr [bp+@@CPellets]
-		pop	si
-		pop	bp
-		retf
-sub_30047	endp
-main_38__TEXT	ends
-
-main_38___TEXT	segment	byte public 'CODE' use16
 	extern @CPellets@add_pattern$qii16pellet_pattern_ti:proc
 	extern @CPellets@add_single$qiiii15pellet_motion_tiii:proc
 	extern @CPellets@motion_type_apply_for_cur$qv:proc
 	extern @CPellets@visible_after_hittests_for_cur$qii:proc
 	extern _pellet_render:proc
+main_38_TEXT	ends
+
+main_38__TEXT	segment	byte public 'CODE' use16
+		assume cs:main_38
+		assume es:nothing, ss:nothing, ds:_DATA, fs:nothing, gs:nothing
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -54609,7 +54541,7 @@ sub_30F70	endp
 
 ; ---------------------------------------------------------------------------
 		dw 0
-main_38___TEXT	ends
+main_38__TEXT	ends
 
 	.data