glx: Fix _glapi_add_dispatch

We never need to generate stubs, because those conditions can't happen
in the server.  Yank that code out, but keep the bookkeeping for which
extension functions are registered so the DRI driver doesn't get
confused.

As a pleasant bonus, we're now friendlier for environments like selinux
that make runtime code generation difficult, and we're portable to more
arches since we don't have to port the assembly stubs.

Fixes the following clutter conformance tests (indirect rendering,
llvmpipe driver):

    test-cogl-backface-culling
    test-cogl-materials
    test-cogl-readpixels
    test-cogl-texture-mipmaps
    test-cogl-texture-get-set-data
    test-cogl-viewport
    test-cogl-offscreen

Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Adam Jackson <ajax@redhat.com>

1 files changed, 20 insertions, 200 deletions

diff --git a/glx/glapi.c b/glx/glapi.c
index 8ac17cdfe..7cb849535 100644
--- a/glx/glapi.c
+++ b/glx/glapi.c
@@ -51,9 +51,6 @@
 static void init_glapi_relocs(void);
 #endif
 
-static _glapi_proc generate_entrypoint(GLuint functionOffset);
-static void fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset);
-
 /**
  * \name Current dispatch and current context control variables
  *
@@ -114,23 +111,6 @@ PUBLIC void *_glapi_Context = NULL;
 #endif /* defined(GLX_USE_TLS) */
 /*@}*/
 
-
-/**
- * strdup() is actually not a standard ANSI C or POSIX routine.
- * Irix will not define it if ANSI mode is in effect.
- */
-static char *
-str_dup(const char *str)
-{
-   char *copy;
-   copy = (char*) malloc(strlen(str) + 1);
-   if (!copy)
-      return NULL;
-   strcpy(copy, str);
-   return copy;
-}
-
-
 /*
  * xserver's gl is not multithreaded, we promise.
  */
@@ -298,7 +278,6 @@ struct _glapi_function {
     */
    const char * name;
 
-
    /**
     * Text string that describes the types of the parameters passed to the
     * named function.   Parameter types are converted to characters using the
@@ -310,164 +289,17 @@ struct _glapi_function {
     */
    const char * parameter_signature;
 
-
    /**
     * Offset in the dispatch table where the pointer to the real function is
     * located.  If the driver has not requested that the named function be
     * added to the dispatch table, this will have the value ~0.
     */
    unsigned dispatch_offset;
-
-
-   /**
-    * Pointer to the dispatch stub for the named function.
-    * 
-    * \todo
-    * The semantic of this field should be changed slightly.  Currently, it
-    * is always expected to be non-\c NULL.  However, it would be better to
-    * only allocate the entry-point stub when the application requests the
-    * function via \c glXGetProcAddress.  This would save memory for all the
-    * functions that the driver exports but that the application never wants
-    * to call.
-    */
-   _glapi_proc dispatch_stub;
 };
 
-
 static struct _glapi_function ExtEntryTable[MAX_EXTENSION_FUNCS];
 static GLuint NumExtEntryPoints = 0;
 
-#ifdef USE_SPARC_ASM
-extern void __glapi_sparc_icache_flush(unsigned int *);
-#endif
-
-/**
- * Generate a dispatch function (entrypoint) which jumps through
- * the given slot number (offset) in the current dispatch table.
- * We need assembly language in order to accomplish this.
- */
-static _glapi_proc
-generate_entrypoint(GLuint functionOffset)
-{
-#if defined(USE_X86_ASM)
-   /* 32 is chosen as something of a magic offset.  For x86, the dispatch
-    * at offset 32 is the first one where the offset in the
-    * "jmp OFFSET*4(%eax)" can't be encoded in a single byte.
-    */
-   const GLubyte * const template_func = gl_dispatch_functions_start 
-     + (DISPATCH_FUNCTION_SIZE * 32);
-   GLubyte * const code = (GLubyte *) malloc(DISPATCH_FUNCTION_SIZE);
-
-
-   if ( code != NULL ) {
-      (void) memcpy(code, template_func, DISPATCH_FUNCTION_SIZE);
-      fill_in_entrypoint_offset( (_glapi_proc) code, functionOffset );
-   }
-
-   return (_glapi_proc) code;
-#elif defined(USE_SPARC_ASM)
-
-#ifdef __arch64__
-   static const unsigned int insn_template[] = {
-	   0x05000000,	/* sethi	%uhi(_glapi_Dispatch), %g2	*/
-	   0x03000000,	/* sethi	%hi(_glapi_Dispatch), %g1	*/
-	   0x8410a000,	/* or		%g2, %ulo(_glapi_Dispatch), %g2	*/
-	   0x82106000,	/* or		%g1, %lo(_glapi_Dispatch), %g1	*/
-	   0x8528b020,	/* sllx		%g2, 32, %g2			*/
-	   0xc2584002,	/* ldx		[%g1 + %g2], %g1		*/
-	   0x05000000,	/* sethi	%hi(8 * glapioffset), %g2	*/
-	   0x8410a000,	/* or		%g2, %lo(8 * glapioffset), %g2	*/
-	   0xc6584002,	/* ldx		[%g1 + %g2], %g3		*/
-	   0x81c0c000,	/* jmpl		%g3, %g0			*/
-	   0x01000000	/*  nop						*/
-   };
-#else
-   static const unsigned int insn_template[] = {
-	   0x03000000,	/* sethi	%hi(_glapi_Dispatch), %g1	  */
-	   0xc2006000,	/* ld		[%g1 + %lo(_glapi_Dispatch)], %g1 */
-	   0xc6006000,	/* ld		[%g1 + %lo(4*glapioffset)], %g3	  */
-	   0x81c0c000,	/* jmpl		%g3, %g0			  */
-	   0x01000000	/*  nop						  */
-   };
-#endif /* __arch64__ */
-   unsigned int *code = (unsigned int *) malloc(sizeof(insn_template));
-   unsigned long glapi_addr = (unsigned long) &_glapi_Dispatch;
-   if (code) {
-      memcpy(code, insn_template, sizeof(insn_template));
-
-#ifdef __arch64__
-      code[0] |= (glapi_addr >> (32 + 10));
-      code[1] |= ((glapi_addr & 0xffffffff) >> 10);
-      __glapi_sparc_icache_flush(&code[0]);
-      code[2] |= ((glapi_addr >> 32) & ((1 << 10) - 1));
-      code[3] |= (glapi_addr & ((1 << 10) - 1));
-      __glapi_sparc_icache_flush(&code[2]);
-      code[6] |= ((functionOffset * 8) >> 10);
-      code[7] |= ((functionOffset * 8) & ((1 << 10) - 1));
-      __glapi_sparc_icache_flush(&code[6]);
-#else
-      code[0] |= (glapi_addr >> 10);
-      code[1] |= (glapi_addr & ((1 << 10) - 1));
-      __glapi_sparc_icache_flush(&code[0]);
-      code[2] |= (functionOffset * 4);
-      __glapi_sparc_icache_flush(&code[2]);
-#endif /* __arch64__ */
-   }
-   return (_glapi_proc) code;
-#else
-   (void) functionOffset;
-   return NULL;
-#endif /* USE_*_ASM */
-}
-
-
-/**
- * This function inserts a new dispatch offset into the assembly language
- * stub that was generated with the preceeding function.
- */
-static void
-fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset)
-{
-#if defined(USE_X86_ASM)
-   GLubyte * const code = (GLubyte *) entrypoint;
-
-#if DISPATCH_FUNCTION_SIZE == 32
-   *((unsigned int *)(code + 11)) = 4 * offset;
-   *((unsigned int *)(code + 22)) = 4 * offset;
-#elif DISPATCH_FUNCTION_SIZE == 16 && defined( GLX_USE_TLS )
-   *((unsigned int *)(code +  8)) = 4 * offset;
-#elif DISPATCH_FUNCTION_SIZE == 16
-   *((unsigned int *)(code +  7)) = 4 * offset;
-#else
-# error Invalid DISPATCH_FUNCTION_SIZE!
-#endif
-
-#elif defined(USE_SPARC_ASM)
-
-   /* XXX this hasn't been tested! */
-   unsigned int *code = (unsigned int *) entrypoint;
-#ifdef __arch64__
-   code[6] = 0x05000000;  /* sethi	%hi(8 * glapioffset), %g2	*/
-   code[7] = 0x8410a000;  /* or		%g2, %lo(8 * glapioffset), %g2	*/
-   code[6] |= ((offset * 8) >> 10);
-   code[7] |= ((offset * 8) & ((1 << 10) - 1));
-   __glapi_sparc_icache_flush(&code[6]);
-#else /* __arch64__ */
-   code[2] = 0xc6006000;  /* ld		[%g1 + %lo(4*glapioffset)], %g3	  */
-   code[2] |= (offset * 4);
-   __glapi_sparc_icache_flush(&code[2]);
-#endif /* __arch64__ */
-
-#else
-
-   /* an unimplemented architecture */
-   (void) entrypoint;
-   (void) offset;
-
-#endif /* USE_*_ASM */
-}
-
-
 /**
  * Generate new entrypoint
  *
@@ -487,16 +319,12 @@ add_function_name( const char * funcName )
    struct _glapi_function * entry = NULL;
    
    if (NumExtEntryPoints < MAX_EXTENSION_FUNCS) {
-      _glapi_proc entrypoint = generate_entrypoint(~0);
-      if (entrypoint != NULL) {
-	 entry = & ExtEntryTable[NumExtEntryPoints];
-
-	 ExtEntryTable[NumExtEntryPoints].name = str_dup(funcName);
-	 ExtEntryTable[NumExtEntryPoints].parameter_signature = NULL;
-	 ExtEntryTable[NumExtEntryPoints].dispatch_offset = ~0;
-	 ExtEntryTable[NumExtEntryPoints].dispatch_stub = entrypoint;
-	 NumExtEntryPoints++;
-      }
+      entry = &ExtEntryTable[NumExtEntryPoints];
+
+      ExtEntryTable[NumExtEntryPoints].name = strdup(funcName);
+      ExtEntryTable[NumExtEntryPoints].parameter_signature = NULL;
+      ExtEntryTable[NumExtEntryPoints].dispatch_offset = ~0;
+      NumExtEntryPoints++;
    }
 
    return entry;
@@ -565,14 +393,13 @@ _glapi_add_dispatch( const char * const * function_names,
    int new_offset;
 
 
-   (void) memset( is_static, 0, sizeof( is_static ) );
-   (void) memset( entry, 0, sizeof( entry ) );
+   (void) memset(is_static, 0, sizeof(is_static));
+   (void) memset(entry, 0, sizeof(entry));
 
-   for ( i = 0 ; function_names[i] != NULL ; i++ ) {
-      /* Do some trivial validation on the name of the function.
-       */
+   for (i = 0 ; function_names[i] != NULL ; i++) {
+      /* Do some trivial validation on the name of the function. */
 
-      if (!function_names[i] || function_names[i][0] != 'g' || function_names[i][1] != 'l')
+      if (function_names[i][0] != 'g' || function_names[i][1] != 'l')
 	return GL_FALSE;
    
       /* Determine if the named function already exists.  If the function does
@@ -586,7 +413,7 @@ _glapi_add_dispatch( const char * const * function_names,
 	  * FIXME: the parameter signature for static functions?
 	  */
 
-	 if ( (offset != ~0) && (new_offset != offset) ) {
+	 if ((offset != ~0) && (new_offset != offset)) {
 	    return -1;
 	 }
 
@@ -594,20 +421,17 @@ _glapi_add_dispatch( const char * const * function_names,
 	 offset = new_offset;
       }
    
-   
-      for ( j = 0 ; j < NumExtEntryPoints ; j++ ) {
+      for (j = 0; j < NumExtEntryPoints; j++) {
 	 if (strcmp(ExtEntryTable[j].name, function_names[i]) == 0) {
 	    /* The offset may be ~0 if the function name was added by
 	     * glXGetProcAddress but never filled in by the driver.
 	     */
 
 	    if (ExtEntryTable[j].dispatch_offset != ~0) {
-	       if (strcmp(real_sig, ExtEntryTable[j].parameter_signature) 
-		   != 0) {
+	       if (strcmp(real_sig, ExtEntryTable[j].parameter_signature) != 0)
 		  return -1;
-	       }
 
-	       if ( (offset != ~0) && (ExtEntryTable[j].dispatch_offset != offset) ) {
+	       if ((offset != ~0) && (ExtEntryTable[j].dispatch_offset != offset)) {
 		  return -1;
 	       }
 
@@ -625,19 +449,15 @@ _glapi_add_dispatch( const char * const * function_names,
       next_dynamic_offset++;
    }
 
-   for ( i = 0 ; function_names[i] != NULL ; i++ ) {
-      if (! is_static[i] ) {
+   for (i = 0 ; function_names[i] != NULL ; i++) {
+      if (!is_static[i]) {
 	 if (entry[i] == NULL) {
-	    entry[i] = add_function_name( function_names[i] );
-	    if (entry[i] == NULL) {
-	       /* FIXME: Possible memory leak here.
-		*/
+	    entry[i] = add_function_name(function_names[i]);
+	    if (entry[i] == NULL)
 	       return -1;
-	    }
 	 }
 
-	 entry[i]->parameter_signature = str_dup(real_sig);
-	 fill_in_entrypoint_offset(entry[i]->dispatch_stub, offset);
+	 entry[i]->parameter_signature = strdup(real_sig);
 	 entry[i]->dispatch_offset = offset;
       }
    }