Use tcc and the emitted C code from s_fragprog_to_c.c to dynamically compile

and execute fragment programs.  Very limited and experimental, but works
well enough to run arbfplight.c.

	http://fabrice.bellard.free.fr/tcc/

Compile with 'make linux-tcc', being sure to make clean first.

1 files changed, 185 insertions, 0 deletions

diff --git a/src/mesa/swrast/s_tcc.c b/src/mesa/swrast/s_tcc.c
new file mode 100644
index 00000000000..3d8f550ece7
--- /dev/null
+++ b/src/mesa/swrast/s_tcc.c
@@ -0,0 +1,185 @@
+/*
+ * Mesa 3-D graphics library
+ * Version:  6.1
+ *
+ * Copyright (C) 1999-2004  Brian Paul   All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/* An attempt to hook s_fragprog_to_c.c up to libtcc.a to try &
+ * generate some real code.
+ *
+ * TCC isn't threadsafe, so it will need additional locking help if we
+ * end up using it as a backend in mesa.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+
+
+#include "glheader.h"
+#include "colormac.h"
+#include "context.h"
+#include "nvfragprog.h"
+#include "macros.h"
+#include "program.h"
+
+#include "s_nvfragprog.h"
+#include "s_texture.h"
+
+#ifdef USE_TCC
+
+#include <libtcc.h>
+
+typedef int (*cfunc)( void *ctx, 
+		      const GLfloat (*local_param)[4], 
+		      const GLfloat (*env_param)[4], 
+		      const struct program_parameter *state_param, 
+		      const GLfloat (*interp)[4], 
+		      GLfloat (*outputs)[4]);
+
+
+static cfunc current_func;
+static struct fragment_program *current_program;
+static TCCState *current_tcc_state;
+
+
+static void TEX( void *cc, const float *texcoord, int unit, float *result )
+{
+   GLcontext *ctx = (GLcontext *)cc;
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   GLfloat lambda = 1.0;	/* hack */
+   GLchan rgba[4];
+
+   swrast->TextureSample[unit](ctx, unit, ctx->Texture.Unit[unit]._Current,
+                               1, (const GLfloat (*)[4]) texcoord,
+                               &lambda, &rgba);
+
+   result[0] = CHAN_TO_FLOAT(rgba[0]);
+   result[1] = CHAN_TO_FLOAT(rgba[1]);
+   result[2] = CHAN_TO_FLOAT(rgba[2]);
+   result[3] = CHAN_TO_FLOAT(rgba[3]);
+}
+
+
+static void TXB( void *cc, const float *texcoord, int unit, float *result )
+{
+   GLcontext *ctx = (GLcontext *)cc;
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   GLfloat lambda = 1.0;	/* hack */
+   GLchan rgba[4];
+
+   /* texcoord[3] is the bias to add to lambda */
+   lambda += texcoord[3];
+
+
+   /* Is it necessary to reset texcoord[3] to 1 at this point?
+    */
+   swrast->TextureSample[unit](ctx, unit, ctx->Texture.Unit[unit]._Current,
+                               1, (const GLfloat (*)[4]) texcoord,
+                               &lambda, &rgba);
+
+   result[0] = CHAN_TO_FLOAT(rgba[0]);
+   result[1] = CHAN_TO_FLOAT(rgba[1]);
+   result[2] = CHAN_TO_FLOAT(rgba[2]);
+   result[3] = CHAN_TO_FLOAT(rgba[3]);
+}
+
+
+static void TXP( void *cc, const float *texcoord, int unit, float *result )
+{
+   /* I think that TEX needs to undo the perspective divide which has
+    * already occurred.  In the meantime, TXP is correct to do this:
+    */
+   TEX( cc, texcoord, unit, result );
+}
+
+
+static cfunc codegen( TCCState *s, const char *prog, const char *fname )
+{
+    unsigned long val;
+
+    if (s) 
+       tcc_delete(s);
+    
+    s = tcc_new();
+    if (!s) 
+       return 0;
+
+    tcc_set_output_type(s, TCC_OUTPUT_MEMORY);
+    tcc_compile_string(s, prog);
+
+/*     tcc_add_dll("/usr/lib/libm.so"); */
+
+    tcc_add_symbol(s, "TEX", (unsigned long)&TEX);
+    tcc_add_symbol(s, "TXB", (unsigned long)&TXB);
+    tcc_add_symbol(s, "TXP", (unsigned long)&TXP);
+
+
+    tcc_relocate(s);
+    tcc_get_symbol(s, &val, fname);
+    return (cfunc) val;
+}
+
+/* TCC isn't threadsafe and even seems not to like having more than
+ * one TCCState created or used at any one time in a single threaded
+ * environment.  So, this code is all for investigation only and can't
+ * currently be used in Mesa proper.
+ *
+ * I've taken some liberties with globals myself, now.
+ */
+GLboolean
+_swrast_execute_codegen_program( GLcontext *ctx,
+			 const struct fragment_program *program, GLuint maxInst,
+			 struct fp_machine *machine, const struct sw_span *span,
+			 GLuint column )
+{
+   if (program != current_program) {
+      
+      _swrast_translate_program( ctx );
+
+      fprintf(stderr, "%s: compiling:\n%s\n", __FUNCTION__, program->c_str);
+
+      current_program = program;
+      current_func = codegen( current_tcc_state, program->c_str, 
+			      "run_program" );
+   }
+
+   assert(current_func);
+
+   return current_func( ctx,
+			program->Base.LocalParams,
+ 			(const GLfloat (*)[4])ctx->FragmentProgram.Parameters, 
+			program->Parameters->Parameters,
+			(const GLfloat (*)[4])machine->Inputs,
+			machine->Outputs );
+}
+
+#else  /* USE_TCC */
+
+GLboolean
+_swrast_execute_codegen_program( GLcontext *ctx,
+			 const struct fragment_program *program, GLuint maxInst,
+			 struct fp_machine *machine, const struct sw_span *span,
+			 GLuint column )
+{
+   return 0;
+}
+
+#endif