glide2x, grDrawTriangle() dispatch code for cvg and h3:

It fails to build for linux with the current compiler flags:

- static builds:
gdraw.c: In function `grDrawTriangle':
gdraw.c:757: error: bp cannot be used in asm here

- shared lib (-fPIC) builds:
gdraw.c: In function `grDrawTriangle':
gdraw.c:731: error: PIC register `ebx' clobbered in `asm'

Only if I use '-DBIG_OPT -fomit-frame-pointer', _then_ it builds into:

00000a20 <grDrawTriangle>:
     a20:	a1 2c 00 00 00       	mov    0x2c,%eax
     a25:	ff a0 50 03 00 00    	jmp    *0x350(%eax)
     a2b:	c3                   	ret
     a2c:	8d 74 26 00          	lea    0x0(%esi,%eiz,1),%esi

... which is good but only for static builds.  The PIC build still
fails with the above message with my gcc3.4 or gcc4.x.

So, I moved the x86 dispatch code to a new xdrawtri.asm, for linux,
and even for MSVC without any prologue/epilogue like the following:
  movl (_GlideRoot + curGC),%eax
  jmp  *kTriProcOffset(%eax)

Let's see how this goes.

glide2x/cvg/glide/src/Makefile.win32

@@ -103,6 +103,8 @@ override USE_FIFO = 1
 ifeq ($(USE_X86),1)
 CDEFS += -DGLIDE_DISPATCH_SETUP=1 -DGLIDE_DISPATCH_DOWNLOAD=1
 override USE_FIFO = 1
+CDEFS += -DHAVE_XDRAWTRI_ASM=1
+override USE_DRAWTRI_ASM = 1
 else
 CDEFS += -DGLIDE_USE_C_TRISETUP=1
 endif
@@ -187,6 +189,9 @@ GLIDE_OBJECTS = \
 	fpu.obj \
 	xtexdl_def.obj
 
+ifeq ($(USE_DRAWTRI_ASM),1)
+GLIDE_OBJECTS += xdrawtri.obj
+endif
 ifeq ($(USE_X86),1)
 GLIDE_OBJECTS += \
 	xdraw2_def.obj
@@ -268,6 +273,8 @@ xdraw2_3dnow.obj: xdraw2.asm
 	$(AS) -o $@ $(ASFLAGS) -DGL_AMD3D=1 $<
 xtexdl_3dnow.obj: xtexdl.asm
 	$(AS) -o $@ $(ASFLAGS) -DGL_AMD3D=1 $<
+xdrawtri.obj: xdrawtri.asm
+	$(AS) -o $@ $(ASFLAGS) $<
 
 $(GLIDE_OBJECTS): fxinline.h fxgasm.h
 

glide2x/cvg/glide/src/gdraw.c

@@ -649,7 +649,8 @@ all_done:                       /* come here on degenerate lines */
 /*---------------------------------------------------------------------------
  ** grDrawTriangle
  */
-#if (GLIDE_PLATFORM & GLIDE_OS_WIN32) && !GLIDE_USE_C_TRISETUP && !defined(GLIDE_DEBUG)
+#ifndef HAVE_XDRAWTRI_ASM	/* grDrawTriangle() not in asm */
+#if defined(_MSC_VER) && !GLIDE_USE_C_TRISETUP && !defined(GLIDE_DEBUG)
 __declspec(naked)
 #endif
 GR_ENTRY(grDrawTriangle, void, (const GrVertex *a, const GrVertex *b, const GrVertex *c))
@@ -693,8 +694,8 @@ GR_ENTRY(grDrawTriangle, void, (const GrVertex *a, const GrVertex *b, const GrVe
 
 all_done:
   GR_END();
-#else
+
-#if defined(__MSC__)
+#elif defined(_MSC_VER)
   {
     __asm {
       mov edx, [_GlideRoot + kCurGCOffset];
@@ -702,59 +703,13 @@ all_done:
       jmp eax;
     }
   }
-#endif
-#if defined( __linux__ )
 
-  /* Here's the basic strategy for this dispatch code:
+#else
-   *   We jump to _GlideRoot.curGC->archDispatchProcs.triSetupProc
+#error "Write triangle proc dispatch for this compiler"
-   *   which contains code that looks like a function, we leave the
-   *   paramters passed to grDrawTriangle on the stack and the dispatched
-   *   function picks them up.  However we have to compensate for 
-   *   the compiler pushing anything on the stack.  The following describes
-   *   why and when we have to pop.
-   *
-   * BIG_OPT: gcc pushes a frame pointer to maintain things, BIG_OPT
-   *          turns on -fomit-frame-pointer so we don't have to pop it.
-   *
-   * PIC:     When using position independant code gcc stores eip in ebx
-   *          so it saves ebx from the previous call automatically.  
-   *          Therefore, once we have the jump address we have to pop ebx
-   *          to restore the stack.  
-   *
-   * The syntax is further complicated by the fact that gcc can (and will)
-   * emit code between the asm statements, so they all need to be in a single
-   * asm statement, wrapped with #ifdef's.  This means we have fun with 
-   * deciding if we need to list trashed registers and when we need commas
-   * between them.
-   */
-
-  asm (
-#if defined(PIC)
-       "popl %%ebx\n\t"
-#endif 
-#if !defined(BIG_OPT)
-       "popl %%ebp\n\t"
-#endif
-       "jmp *%0" 
-       : /* no outputs */        
-       : "m" (_GlideRoot.curGC->curArchProcs.triSetupProc)
-#if defined (PIC) || !defined (BIG_OPT)
-       :
-#endif
-#if defined (PIC)
-        "ebx"
-#endif
-#if defined (PIC) && !defined (BIG_OPT)
-       ,
-#endif
-#if !defined(BIG_OPT)
-        "ebp"
-#endif
-       );
-#endif
 #endif
 #undef FN_NAME
 } /* grDrawTriangle */
+#endif /* HAVE_XDRAWTRI_ASM */
 
 /*---------------------------------------------------------------------------
  ** grDrawPlanarPolygon

glide2x/cvg/glide/src/makefile.linux

@@ -105,6 +105,8 @@ override USE_FIFO = 1
 ifeq ($(USE_X86),1)
 CDEFS += -DGLIDE_DISPATCH_SETUP=1 -DGLIDE_DISPATCH_DOWNLOAD=1
 override USE_FIFO = 1
+CDEFS += -DHAVE_XDRAWTRI_ASM=1
+override USE_DRAWTRI_ASM = 1
 else
 CDEFS += -DGLIDE_USE_C_TRISETUP=1
 endif
@@ -187,6 +189,9 @@ GLIDE_OBJECTS = \
 	fpu.o \
 	xtexdl_def.o
 
+ifeq ($(USE_DRAWTRI_ASM),1)
+GLIDE_OBJECTS += xdrawtri.o
+endif
 ifeq ($(USE_X86),1)
 GLIDE_OBJECTS += \
 	xdraw2_def.o
@@ -277,6 +282,8 @@ xdraw2_3dnow.o: xdraw2.asm
 	$(AS) -o $@ $(ASFLAGS) -DGL_AMD3D=1 $<
 xtexdl_3dnow.o: xtexdl.asm
 	$(AS) -o $@ $(ASFLAGS) -DGL_AMD3D=1 $<
+xdrawtri.o: xdrawtri.asm
+	$(AS) -o $@ $(ASFLAGS) $<
 
 #cpuid.lo: cpuid.o
 #	$(CP) $< $@
@@ -290,6 +297,8 @@ xdraw2_3dnow.lo: xdraw2_3dnow.o
 	$(CP) $< $@
 xtexdl_3dnow.lo: xtexdl_3dnow.o
 	$(CP) $< $@
+xdrawtri.lo: xdrawtri.o
+	$(CP) $< $@
 
 $(GLIDE_OBJECTS): fxinline.h fxgasm.h
 

glide2x/cvg/glide/src/xdrawtri.asm

@@ -0,0 +1,46 @@
+;; THIS SOFTWARE IS SUBJECT TO COPYRIGHT PROTECTION AND IS OFFERED ONLY
+;; PURSUANT TO THE 3DFX GLIDE GENERAL PUBLIC LICENSE. THERE IS NO RIGHT
+;; TO USE THE GLIDE TRADEMARK WITHOUT PRIOR WRITTEN PERMISSION OF 3DFX
+;; INTERACTIVE, INC. A COPY OF THIS LICENSE MAY BE OBTAINED FROM THE
+;; DISTRIBUTOR OR BY CONTACTING 3DFX INTERACTIVE INC(info@3dfx.com).
+;; THIS PROGRAM IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
+;; EXPRESSED OR IMPLIED. SEE THE 3DFX GLIDE GENERAL PUBLIC LICENSE FOR A
+;; FULL TEXT OF THE NON-WARRANTY PROVISIONS.
+;;
+;; USE, DUPLICATION OR DISCLOSURE BY THE GOVERNMENT IS SUBJECT TO
+;; RESTRICTIONS AS SET FORTH IN SUBDIVISION (C)(1)(II) OF THE RIGHTS IN
+;; TECHNICAL DATA AND COMPUTER SOFTWARE CLAUSE AT DFARS 252.227-7013,
+;; AND/OR IN SIMILAR OR SUCCESSOR CLAUSES IN THE FAR, DOD OR NASA FAR
+;; SUPPLEMENT. UNPUBLISHED RIGHTS RESERVED UNDER THE COPYRIGHT LAWS OF
+;; THE UNITED STATES.
+;;
+;; COPYRIGHT 3DFX INTERACTIVE, INC. 1999, ALL RIGHTS RESERVED
+
+;; Adapted from gdraw.c:grDrawTriangle() for nasm
+
+%include "xos.inc"
+
+%include "fxgasm.h"
+
+extrn   _GlideRoot
+
+segment SEG_TEXT
+
+align 16
+proc grDrawTriangle, 12
+
+;;mov edx, dword [_GlideRoot+curGC]
+;;mov eax, dword [edx+kTriProcOffset]
+  mov eax, dword [_GlideRoot+curGC]
+  jmp [eax + kTriProcOffset]
+endp
+  align 16
+
+%if XOS == XOS_WIN32
+%ifdef __MINGW32__
+; GNU LD fails with '_' prefix
+export  grDrawTriangle@12
+%else
+export _grDrawTriangle@12
+%endif
+%endif ; _WIN32

glide2x/h3/glide/src/gdraw.c

@@ -653,7 +653,10 @@ all_done:                       /* come here on degenerate lines */
 /*---------------------------------------------------------------------------
  ** grDrawTriangle
  */
-
+#ifndef HAVE_XDRAWTRI_ASM	/* grDrawTriangle() not in asm */
+#if defined(_MSC_VER) && !GLIDE_USE_C_TRISETUP && !defined(GLIDE_DEBUG)
+__declspec(naked)
+#endif
 #ifdef GLIDE3
 GR_ENTRY(grDrawTriangle, void, (void *a, void *b, void *c))
 #else
@@ -716,70 +719,23 @@ GR_ENTRY(grDrawTriangle, void, (const GrVertex *a, const GrVertex *b, const GrVe
 
 all_done:
   GR_END();
-#else
+
-#if defined(__MSC__)
+#elif defined(_MSC_VER)
   {
     extern struct _GlideRoot_s _GlideRoot;
-
+    __asm {
-    _asm {
+      mov edx, [_GlideRoot + kCurGCOffset];
-      mov eax, [_GlideRoot + kCurGCOffset];
+      mov eax, [edx + kTriProcOffset];
-      mov eax, [eax + kTriProcOffset];
       jmp eax;
     }
   }
-#endif
-#if defined( __linux__ )
 
-  /* Here's the basic strategy for this dispatch code:
+#else
-   *   We jump to _GlideRoot.curGC->archDispatchProcs.triSetupProc
+#error "Write triangle proc dispatch for this compiler"
-   *   which contains code that looks like a function, we leave the
-   *   paramters passed to grDrawTriangle on the stack and the dispatched
-   *   function picks them up.  However we have to compensate for 
-   *   the compiler pushing anything on the stack.  The following describes
-   *   why and when we have to pop.
-   *
-   * BIG_OPT: gcc pushes a frame pointer to maintain things, BIG_OPT
-   *          turns on -fomit-frame-pointer so we don't have to pop it.
-   *
-   * PIC:     When using position independant code gcc stores eip in ebx
-   *          so it saves ebx from the previous call automatically.  
-   *          Therefore, once we have the jump address we have to pop ebx
-   *          to restore the stack.  
-   *
-   * The syntax is further complicated by the fact that gcc can (and will)
-   * emit code between the asm statements, so they all need to be in a single
-   * asm statement, wrapped with #ifdef's.  This means we have fun with 
-   * deciding if we need to list trashed registers and when we need commas
-   * between them.
-   */
-
-  asm (
-#if defined(PIC)
-       "popl %%ebx\n\t"
-#endif 
-#if !defined(BIG_OPT)
-       "popl %%ebp\n\t"
-#endif
-       "jmp *%0" 
-       : /* no outputs */        
-       :"m" (_GlideRoot.curGC->archDispatchProcs.triSetupProc)
-#if defined (PIC) || !defined (BIG_OPT)
-       :
-#endif
-#if defined (PIC)
-        "ebx"
-#endif
-#if defined (PIC) && !defined (BIG_OPT)
-       ,
-#endif
-#if !defined(BIG_OPT)
-        "ebp"
-#endif
-       );
-#endif
 #endif
 #undef FN_NAME
 } /* grDrawTriangle */
+#endif /* HAVE_XDRAWTRI_ASM */
 
 #ifndef GLIDE3_ALPHA
 /*---------------------------------------------------------------------------

glide2x/h3/glide/src/makefile.linux

@@ -102,6 +102,8 @@ override USE_FIFO = 1
 ifeq ($(USE_X86),1)
 CDEFS += -DGLIDE_DISPATCH_SETUP=1 -DGLIDE_DISPATCH_DOWNLOAD=1
 override USE_FIFO = 1
+CDEFS += -DHAVE_XDRAWTRI_ASM=1
+override USE_DRAWTRI_ASM = 1
 else
 CDEFS += -DGLIDE_USE_C_TRISETUP=1
 endif
@@ -180,6 +182,9 @@ GLIDE_OBJECTS = \
 	cpuid.o \
 	xtexdl_def.o
 
+ifeq ($(USE_DRAWTRI_ASM),1)
+GLIDE_OBJECTS += xdrawtri.o
+endif
 ifeq ($(USE_X86),1)
 GLIDE_OBJECTS += \
 	xdraw2_def.o
@@ -241,8 +246,6 @@ $(GLIDE_LIBDIR)/$(GLIDE_SHARED): $(GLIDE_OBJECTS:.o=.lo)
 #	rules(2)
 ###############################################################################
 
-#using nasm now
-#
 #cpuid.o: cpudtect.S
 #	$(CC) -o $@ -xassembler-with-cpp -c $(CDEFS) $<
 #xdraw2_def.o: xdraw2.S
@@ -251,6 +254,8 @@ $(GLIDE_LIBDIR)/$(GLIDE_SHARED): $(GLIDE_OBJECTS:.o=.lo)
 #	$(CC) -o $@ -xassembler-with-cpp -c $(CDEFS) -DGL_AMD3D=1 $<
 #xtexdl_3dnow.o: xtexdl.S
 #	$(CC) -o $@ -xassembler-with-cpp -c $(CDEFS) -DGL_AMD3D=1 $<
+#xdrawtri.o: xdrawtri.S
+#	$(CC) -o $@ -xassembler-with-cpp -c $(CDEFS) $<
 cpuid.o: cpudtect.asm
 	$(AS) -o $@ $(ASFLAGS) $<
 xdraw2_def.o: xdraw2.asm
@@ -259,6 +264,8 @@ xdraw2_3dnow.o: xdraw2.asm
 	$(AS) -o $@ $(ASFLAGS) -DGL_AMD3D=1 $<
 xtexdl_3dnow.o: xtexdl.asm
 	$(AS) -o $@ $(ASFLAGS) -DGL_AMD3D=1 $<
+xdrawtri.o: xdrawtri.asm
+	$(AS) -o $@ $(ASFLAGS) $<
 
 cpuid.lo: cpuid.o
 	$(CP) $< $@
@@ -268,6 +275,8 @@ xdraw2_3dnow.lo: xdraw2_3dnow.o
 	$(CP) $< $@
 xtexdl_3dnow.lo: xtexdl_3dnow.o
 	$(CP) $< $@
+xdrawtri.lo: xdrawtri.o
+	$(CP) $< $@
 
 $(GLIDE_OBJECTS): fxinline.h fxgasm.h
 

glide2x/h3/glide/src/xdrawtri.S

@@ -0,0 +1,38 @@
+/*
+ * THIS SOFTWARE IS SUBJECT TO COPYRIGHT PROTECTION AND IS OFFERED ONLY
+ * PURSUANT TO THE 3DFX GLIDE GENERAL PUBLIC LICENSE. THERE IS NO RIGHT
+ * TO USE THE GLIDE TRADEMARK WITHOUT PRIOR WRITTEN PERMISSION OF 3DFX
+ * INTERACTIVE, INC. A COPY OF THIS LICENSE MAY BE OBTAINED FROM THE
+ * DISTRIBUTOR OR BY CONTACTING 3DFX INTERACTIVE INC(info@3dfx.com).
+ * THIS PROGRAM IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESSED OR IMPLIED. SEE THE 3DFX GLIDE GENERAL PUBLIC LICENSE FOR A
+ * FULL TEXT OF THE NON-WARRANTY PROVISIONS.
+ *
+ * USE, DUPLICATION OR DISCLOSURE BY THE GOVERNMENT IS SUBJECT TO
+ * RESTRICTIONS AS SET FORTH IN SUBDIVISION (C)(1)(II) OF THE RIGHTS IN
+ * TECHNICAL DATA AND COMPUTER SOFTWARE CLAUSE AT DFARS 252.227-7013,
+ * AND/OR IN SIMILAR OR SUCCESSOR CLAUSES IN THE FAR, DOD OR NASA FAR
+ * SUPPLEMENT. UNPUBLISHED RIGHTS RESERVED UNDER THE COPYRIGHT LAWS OF
+ * THE UNITED STATES.
+ *
+ * COPYRIGHT 3DFX INTERACTIVE, INC. 1999, ALL RIGHTS RESERVED
+ */
+
+/* Adapted from gdraw.c:grDrawTriangle() for gas */
+
+#include "fxgasm.h"
+
+.extern _GlideRoot
+
+.text
+
+.p2align 4,,15
+.globl grDrawTriangle
+.type  grDrawTriangle,@function
+grDrawTriangle:
+/*movl (_GlideRoot+curGC),%edx
+  movl kTriProcOffset(%edx),%eax*/
+  movl (_GlideRoot + curGC),%eax
+  jmp  *kTriProcOffset(%eax)
+
+.p2align 4,,15

glide2x/h3/glide/src/xdrawtri.asm

@@ -0,0 +1,46 @@
+;; THIS SOFTWARE IS SUBJECT TO COPYRIGHT PROTECTION AND IS OFFERED ONLY
+;; PURSUANT TO THE 3DFX GLIDE GENERAL PUBLIC LICENSE. THERE IS NO RIGHT
+;; TO USE THE GLIDE TRADEMARK WITHOUT PRIOR WRITTEN PERMISSION OF 3DFX
+;; INTERACTIVE, INC. A COPY OF THIS LICENSE MAY BE OBTAINED FROM THE
+;; DISTRIBUTOR OR BY CONTACTING 3DFX INTERACTIVE INC(info@3dfx.com).
+;; THIS PROGRAM IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
+;; EXPRESSED OR IMPLIED. SEE THE 3DFX GLIDE GENERAL PUBLIC LICENSE FOR A
+;; FULL TEXT OF THE NON-WARRANTY PROVISIONS.
+;;
+;; USE, DUPLICATION OR DISCLOSURE BY THE GOVERNMENT IS SUBJECT TO
+;; RESTRICTIONS AS SET FORTH IN SUBDIVISION (C)(1)(II) OF THE RIGHTS IN
+;; TECHNICAL DATA AND COMPUTER SOFTWARE CLAUSE AT DFARS 252.227-7013,
+;; AND/OR IN SIMILAR OR SUCCESSOR CLAUSES IN THE FAR, DOD OR NASA FAR
+;; SUPPLEMENT. UNPUBLISHED RIGHTS RESERVED UNDER THE COPYRIGHT LAWS OF
+;; THE UNITED STATES.
+;;
+;; COPYRIGHT 3DFX INTERACTIVE, INC. 1999, ALL RIGHTS RESERVED
+
+;; Adapted from gdraw.c:grDrawTriangle() for nasm
+
+%include "xos.inc"
+
+%include "fxgasm.h"
+
+extrn   _GlideRoot
+
+segment SEG_TEXT
+
+align 16
+proc grDrawTriangle, 12
+
+;;mov edx, dword [_GlideRoot+curGC]
+;;mov eax, dword [edx+kTriProcOffset]
+  mov eax, dword [_GlideRoot+curGC]
+  jmp [eax + kTriProcOffset]
+endp
+  align 16
+
+%if XOS == XOS_WIN32
+%ifdef __MINGW32__
+; GNU LD fails with '_' prefix
+export  grDrawTriangle@12
+%else
+export _grDrawTriangle@12
+%endif
+%endif ; _WIN32