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|
/*
* Mesa 3-D graphics library
* Version: 7.3
*
* Copyright (C) 2008 Brian Paul All Rights Reserved.
* Copyright (C) 2009 VMware, Inc. 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.
*/
/**
* \file slang_link.c
* GLSL linker
* \author Brian Paul
*/
#include "main/imports.h"
#include "main/context.h"
#include "main/hash.h"
#include "main/macros.h"
#include "shader/program.h"
#include "shader/prog_instruction.h"
#include "shader/prog_parameter.h"
#include "shader/prog_print.h"
#include "shader/prog_statevars.h"
#include "shader/prog_uniform.h"
#include "shader/shader_api.h"
#include "slang_link.h"
/** cast wrapper */
static struct gl_vertex_program *
vertex_program(struct gl_program *prog)
{
assert(prog->Target == GL_VERTEX_PROGRAM_ARB);
return (struct gl_vertex_program *) prog;
}
/** cast wrapper */
static struct gl_fragment_program *
fragment_program(struct gl_program *prog)
{
assert(prog->Target == GL_FRAGMENT_PROGRAM_ARB);
return (struct gl_fragment_program *) prog;
}
/**
* Record a linking error.
*/
static void
link_error(struct gl_shader_program *shProg, const char *msg)
{
if (shProg->InfoLog) {
_mesa_free(shProg->InfoLog);
}
shProg->InfoLog = _mesa_strdup(msg);
shProg->LinkStatus = GL_FALSE;
}
/**
* Check if the given bit is either set or clear in both bitfields.
*/
static GLboolean
bits_agree(GLbitfield flags1, GLbitfield flags2, GLbitfield bit)
{
return (flags1 & bit) == (flags2 & bit);
}
/**
* Linking varying vars involves rearranging varying vars so that the
* vertex program's output varyings matches the order of the fragment
* program's input varyings.
* We'll then rewrite instructions to replace PROGRAM_VARYING with either
* PROGRAM_INPUT or PROGRAM_OUTPUT depending on whether it's a vertex or
* fragment shader.
* This is also where we set program Input/OutputFlags to indicate
* which inputs are centroid-sampled, invariant, etc.
*/
static GLboolean
link_varying_vars(struct gl_shader_program *shProg, struct gl_program *prog)
{
GLuint *map, i, firstVarying, newFile;
GLbitfield *inOutFlags;
map = (GLuint *) malloc(prog->Varying->NumParameters * sizeof(GLuint));
if (!map)
return GL_FALSE;
/* Varying variables are treated like other vertex program outputs
* (and like other fragment program inputs). The position of the
* first varying differs for vertex/fragment programs...
* Also, replace File=PROGRAM_VARYING with File=PROGRAM_INPUT/OUTPUT.
*/
if (prog->Target == GL_VERTEX_PROGRAM_ARB) {
firstVarying = VERT_RESULT_VAR0;
newFile = PROGRAM_OUTPUT;
inOutFlags = prog->OutputFlags;
}
else {
assert(prog->Target == GL_FRAGMENT_PROGRAM_ARB);
firstVarying = FRAG_ATTRIB_VAR0;
newFile = PROGRAM_INPUT;
inOutFlags = prog->InputFlags;
}
for (i = 0; i < prog->Varying->NumParameters; i++) {
/* see if this varying is in the linked varying list */
const struct gl_program_parameter *var = prog->Varying->Parameters + i;
GLint j = _mesa_lookup_parameter_index(shProg->Varying, -1, var->Name);
if (j >= 0) {
/* varying is already in list, do some error checking */
const struct gl_program_parameter *v =
&shProg->Varying->Parameters[j];
if (var->Size != v->Size) {
link_error(shProg, "mismatched varying variable types");
return GL_FALSE;
}
if (!bits_agree(var->Flags, v->Flags, PROG_PARAM_BIT_CENTROID)) {
char msg[100];
_mesa_snprintf(msg, sizeof(msg),
"centroid modifier mismatch for '%s'", var->Name);
link_error(shProg, msg);
return GL_FALSE;
}
if (!bits_agree(var->Flags, v->Flags, PROG_PARAM_BIT_INVARIANT)) {
char msg[100];
_mesa_snprintf(msg, sizeof(msg),
"invariant modifier mismatch for '%s'", var->Name);
link_error(shProg, msg);
return GL_FALSE;
}
}
else {
/* not already in linked list */
j = _mesa_add_varying(shProg->Varying, var->Name, var->Size,
var->Flags);
}
/* Map varying[i] to varying[j].
* Plus, set prog->Input/OutputFlags[] as described above.
* Note: the loop here takes care of arrays or large (sz>4) vars.
*/
{
GLint sz = var->Size;
while (sz > 0) {
inOutFlags[firstVarying + j] = var->Flags;
/*printf("Link varying from %d to %d\n", i, j);*/
map[i++] = j++;
sz -= 4;
}
i--; /* go back one */
}
}
/* OK, now scan the program/shader instructions looking for varying vars,
* replacing the old index with the new index.
*/
for (i = 0; i < prog->NumInstructions; i++) {
struct prog_instruction *inst = prog->Instructions + i;
GLuint j;
if (inst->DstReg.File == PROGRAM_VARYING) {
inst->DstReg.File = newFile;
inst->DstReg.Index = map[ inst->DstReg.Index ] + firstVarying;
}
for (j = 0; j < 3; j++) {
if (inst->SrcReg[j].File == PROGRAM_VARYING) {
inst->SrcReg[j].File = newFile;
inst->SrcReg[j].Index = map[ inst->SrcReg[j].Index ] + firstVarying;
}
}
}
free(map);
/* these will get recomputed before linking is completed */
prog->InputsRead = 0x0;
prog->OutputsWritten = 0x0;
return GL_TRUE;
}
/**
* Build the shProg->Uniforms list.
* This is basically a list/index of all uniforms found in either/both of
* the vertex and fragment shaders.
*
* About uniforms:
* Each uniform has two indexes, one that points into the vertex
* program's parameter array and another that points into the fragment
* program's parameter array. When the user changes a uniform's value
* we have to change the value in the vertex and/or fragment program's
* parameter array.
*
* This function will be called twice to set up the two uniform->parameter
* mappings.
*
* If a uniform is only present in the vertex program OR fragment program
* then the fragment/vertex parameter index, respectively, will be -1.
*/
static GLboolean
link_uniform_vars(GLcontext *ctx,
struct gl_shader_program *shProg,
struct gl_program *prog,
GLuint *numSamplers)
{
GLuint samplerMap[200]; /* max number of samplers declared, not used */
GLuint i;
for (i = 0; i < prog->Parameters->NumParameters; i++) {
const struct gl_program_parameter *p = prog->Parameters->Parameters + i;
/*
* XXX FIX NEEDED HERE
* We should also be adding a uniform if p->Type == PROGRAM_STATE_VAR.
* For example, modelview matrix, light pos, etc.
* Also, we need to update the state-var name-generator code to
* generate GLSL-style names, like "gl_LightSource[0].position".
* Furthermore, we'll need to fix the state-var's size/datatype info.
*/
if ((p->Type == PROGRAM_UNIFORM || p->Type == PROGRAM_SAMPLER)
&& p->Used) {
/* add this uniform, indexing into the target's Parameters list */
struct gl_uniform *uniform =
_mesa_append_uniform(shProg->Uniforms, p->Name, prog->Target, i);
if (uniform)
uniform->Initialized = p->Initialized;
}
/* The samplerMap[] table we build here is used to remap/re-index
* sampler references by TEX instructions.
*/
if (p->Type == PROGRAM_SAMPLER && p->Used) {
/* Allocate a new sampler index */
GLuint oldSampNum = (GLuint) prog->Parameters->ParameterValues[i][0];
GLuint newSampNum = *numSamplers;
if (newSampNum >= ctx->Const.MaxTextureImageUnits) {
char s[100];
_mesa_sprintf(s, "Too many texture samplers (%u, max is %u)",
newSampNum, ctx->Const.MaxTextureImageUnits);
link_error(shProg, s);
return GL_FALSE;
}
/* save old->new mapping in the table */
if (oldSampNum < Elements(samplerMap))
samplerMap[oldSampNum] = newSampNum;
/* update parameter's sampler index */
prog->Parameters->ParameterValues[i][0] = (GLfloat) newSampNum;
(*numSamplers)++;
}
}
/* OK, now scan the program/shader instructions looking for texture
* instructions using sampler vars. Replace old sampler indexes with
* new ones.
*/
prog->SamplersUsed = 0x0;
for (i = 0; i < prog->NumInstructions; i++) {
struct prog_instruction *inst = prog->Instructions + i;
if (_mesa_is_tex_instruction(inst->Opcode)) {
const GLint oldSampNum = inst->TexSrcUnit;
#if 0
printf("====== remap sampler from %d to %d\n",
inst->TexSrcUnit, samplerMap[ inst->TexSrcUnit ]);
#endif
/* here, texUnit is really samplerUnit */
if (oldSampNum < Elements(samplerMap)) {
const GLuint newSampNum = samplerMap[oldSampNum];
inst->TexSrcUnit = newSampNum;
prog->SamplerTargets[newSampNum] = inst->TexSrcTarget;
prog->SamplersUsed |= (1 << newSampNum);
if (inst->TexShadow) {
prog->ShadowSamplers |= (1 << newSampNum);
}
}
}
}
return GL_TRUE;
}
/**
* Resolve binding of generic vertex attributes.
* For example, if the vertex shader declared "attribute vec4 foobar" we'll
* allocate a generic vertex attribute for "foobar" and plug that value into
* the vertex program instructions.
* But if the user called glBindAttributeLocation(), those bindings will
* have priority.
*/
static GLboolean
_slang_resolve_attributes(struct gl_shader_program *shProg,
const struct gl_program *origProg,
struct gl_program *linkedProg)
{
GLint attribMap[MAX_VERTEX_ATTRIBS];
GLuint i, j;
GLbitfield usedAttributes; /* generics only, not legacy attributes */
assert(origProg != linkedProg);
assert(origProg->Target == GL_VERTEX_PROGRAM_ARB);
assert(linkedProg->Target == GL_VERTEX_PROGRAM_ARB);
if (!shProg->Attributes)
shProg->Attributes = _mesa_new_parameter_list();
if (linkedProg->Attributes) {
_mesa_free_parameter_list(linkedProg->Attributes);
}
linkedProg->Attributes = _mesa_new_parameter_list();
/* Build a bitmask indicating which attribute indexes have been
* explicitly bound by the user with glBindAttributeLocation().
*/
usedAttributes = 0x0;
for (i = 0; i < shProg->Attributes->NumParameters; i++) {
GLint attr = shProg->Attributes->Parameters[i].StateIndexes[0];
usedAttributes |= (1 << attr);
}
/* If gl_Vertex is used, that actually counts against the limit
* on generic vertex attributes. This avoids the ambiguity of
* whether glVertexAttrib4fv(0, v) sets legacy attribute 0 (vert pos)
* or generic attribute[0]. If gl_Vertex is used, we want the former.
*/
if (origProg->InputsRead & VERT_BIT_POS) {
usedAttributes |= 0x1;
}
/* initialize the generic attribute map entries to -1 */
for (i = 0; i < MAX_VERTEX_ATTRIBS; i++) {
attribMap[i] = -1;
}
/*
* Scan program for generic attribute references
*/
for (i = 0; i < linkedProg->NumInstructions; i++) {
struct prog_instruction *inst = linkedProg->Instructions + i;
for (j = 0; j < 3; j++) {
if (inst->SrcReg[j].File == PROGRAM_INPUT &&
inst->SrcReg[j].Index >= VERT_ATTRIB_GENERIC0) {
/*
* OK, we've found a generic vertex attribute reference.
*/
const GLint k = inst->SrcReg[j].Index - VERT_ATTRIB_GENERIC0;
GLint attr = attribMap[k];
if (attr < 0) {
/* Need to figure out attribute mapping now.
*/
const char *name = origProg->Attributes->Parameters[k].Name;
const GLint size = origProg->Attributes->Parameters[k].Size;
const GLenum type =origProg->Attributes->Parameters[k].DataType;
GLint index;
/* See if there's a user-defined attribute binding for
* this name.
*/
index = _mesa_lookup_parameter_index(shProg->Attributes,
-1, name);
if (index >= 0) {
/* Found a user-defined binding */
attr = shProg->Attributes->Parameters[index].StateIndexes[0];
}
else {
/* No user-defined binding, choose our own attribute number.
* Start at 1 since generic attribute 0 always aliases
* glVertex/position.
*/
for (attr = 0; attr < MAX_VERTEX_ATTRIBS; attr++) {
if (((1 << attr) & usedAttributes) == 0)
break;
}
if (attr == MAX_VERTEX_ATTRIBS) {
link_error(shProg, "Too many vertex attributes");
return GL_FALSE;
}
/* mark this attribute as used */
usedAttributes |= (1 << attr);
}
attribMap[k] = attr;
/* Save the final name->attrib binding so it can be queried
* with glGetAttributeLocation().
*/
_mesa_add_attribute(linkedProg->Attributes, name,
size, type, attr);
}
assert(attr >= 0);
/* update the instruction's src reg */
inst->SrcReg[j].Index = VERT_ATTRIB_GENERIC0 + attr;
}
}
}
return GL_TRUE;
}
/**
* Scan program instructions to update the program's NumTemporaries field.
* Note: this implemenation relies on the code generator allocating
* temps in increasing order (0, 1, 2, ... ).
*/
static void
_slang_count_temporaries(struct gl_program *prog)
{
GLuint i, j;
GLint maxIndex = -1;
for (i = 0; i < prog->NumInstructions; i++) {
const struct prog_instruction *inst = prog->Instructions + i;
const GLuint numSrc = _mesa_num_inst_src_regs(inst->Opcode);
for (j = 0; j < numSrc; j++) {
if (inst->SrcReg[j].File == PROGRAM_TEMPORARY) {
if (maxIndex < inst->SrcReg[j].Index)
maxIndex = inst->SrcReg[j].Index;
}
if (inst->DstReg.File == PROGRAM_TEMPORARY) {
if (maxIndex < (GLint) inst->DstReg.Index)
maxIndex = inst->DstReg.Index;
}
}
}
prog->NumTemporaries = (GLuint) (maxIndex + 1);
}
/**
* Scan program instructions to update the program's InputsRead and
* OutputsWritten fields.
*/
static void
_slang_update_inputs_outputs(struct gl_program *prog)
{
GLuint i, j;
GLuint maxAddrReg = 0;
prog->InputsRead = 0x0;
prog->OutputsWritten = 0x0;
for (i = 0; i < prog->NumInstructions; i++) {
const struct prog_instruction *inst = prog->Instructions + i;
const GLuint numSrc = _mesa_num_inst_src_regs(inst->Opcode);
for (j = 0; j < numSrc; j++) {
if (inst->SrcReg[j].File == PROGRAM_INPUT) {
prog->InputsRead |= 1 << inst->SrcReg[j].Index;
if (prog->Target == GL_FRAGMENT_PROGRAM_ARB &&
inst->SrcReg[j].Index == FRAG_ATTRIB_FOGC) {
/* The fragment shader FOGC input is used for fog,
* front-facing and sprite/point coord.
*/
struct gl_fragment_program *fp = fragment_program(prog);
const GLint swz = GET_SWZ(inst->SrcReg[j].Swizzle, 0);
if (swz == SWIZZLE_X)
fp->UsesFogFragCoord = GL_TRUE;
else if (swz == SWIZZLE_Y)
fp->UsesFrontFacing = GL_TRUE;
else if (swz == SWIZZLE_Z || swz == SWIZZLE_W)
fp->UsesPointCoord = GL_TRUE;
}
}
else if (inst->SrcReg[j].File == PROGRAM_ADDRESS) {
maxAddrReg = MAX2(maxAddrReg, (GLuint) (inst->SrcReg[j].Index + 1));
}
}
if (inst->DstReg.File == PROGRAM_OUTPUT) {
prog->OutputsWritten |= 1 << inst->DstReg.Index;
if (inst->DstReg.RelAddr) {
/* If the output attribute is indexed with relative addressing
* we know that it must be a varying or texcoord such as
* gl_TexCoord[i] = v; In this case, mark all the texcoords
* or varying outputs as being written. It's not an error if
* a vertex shader writes varying vars that aren't used by the
* fragment shader. But it is an error for a fragment shader
* to use varyings that are not written by the vertex shader.
*/
if (prog->Target == GL_VERTEX_PROGRAM_ARB) {
if (inst->DstReg.Index == VERT_RESULT_TEX0) {
/* mark all texcoord outputs as written */
const GLbitfield mask =
((1 << MAX_TEXTURE_COORD_UNITS) - 1) << VERT_RESULT_TEX0;
prog->OutputsWritten |= mask;
}
else if (inst->DstReg.Index == VERT_RESULT_VAR0) {
/* mark all generic varying outputs as written */
const GLbitfield mask =
((1 << MAX_VARYING) - 1) << VERT_RESULT_VAR0;
prog->OutputsWritten |= mask;
}
}
}
}
else if (inst->DstReg.File == PROGRAM_ADDRESS) {
maxAddrReg = MAX2(maxAddrReg, inst->DstReg.Index + 1);
}
}
prog->NumAddressRegs = maxAddrReg;
}
/**
* Return a new shader whose source code is the concatenation of
* all the shader sources of the given type.
*/
static struct gl_shader *
concat_shaders(struct gl_shader_program *shProg, GLenum shaderType)
{
struct gl_shader *newShader;
const struct gl_shader *firstShader = NULL;
GLuint shaderLengths[100];
GLchar *source;
GLuint totalLen = 0, len = 0;
GLuint i;
/* compute total size of new shader source code */
for (i = 0; i < shProg->NumShaders; i++) {
const struct gl_shader *shader = shProg->Shaders[i];
if (shader->Type == shaderType) {
shaderLengths[i] = _mesa_strlen(shader->Source);
totalLen += shaderLengths[i];
if (!firstShader)
firstShader = shader;
}
}
source = (GLchar *) _mesa_malloc(totalLen + 1);
if (!source)
return NULL;
/* concatenate shaders */
for (i = 0; i < shProg->NumShaders; i++) {
const struct gl_shader *shader = shProg->Shaders[i];
if (shader->Type == shaderType) {
_mesa_memcpy(source + len, shader->Source, shaderLengths[i]);
len += shaderLengths[i];
}
}
source[len] = '\0';
/*
_mesa_printf("---NEW CONCATENATED SHADER---:\n%s\n------------\n", source);
*/
newShader = CALLOC_STRUCT(gl_shader);
newShader->Type = shaderType;
newShader->Source = source;
newShader->Pragmas = firstShader->Pragmas;
return newShader;
}
/**
* Search the shader program's list of shaders to find the one that
* defines main().
* This will involve shader concatenation and recompilation if needed.
*/
static struct gl_shader *
get_main_shader(GLcontext *ctx,
struct gl_shader_program *shProg, GLenum type)
{
struct gl_shader *shader = NULL;
GLuint i;
/*
* Look for a shader that defines main() and has no unresolved references.
*/
for (i = 0; i < shProg->NumShaders; i++) {
shader = shProg->Shaders[i];
if (shader->Type == type &&
shader->Main &&
!shader->UnresolvedRefs) {
/* All set! */
return shader;
}
}
/*
* There must have been unresolved references during the original
* compilation. Try concatenating all the shaders of the given type
* and recompile that.
*/
shader = concat_shaders(shProg, type);
_slang_compile(ctx, shader);
/* Finally, check if recompiling failed */
if (!shader->CompileStatus ||
!shader->Main ||
shader->UnresolvedRefs) {
link_error(shProg, "Unresolved symbols");
return NULL;
}
return shader;
}
/**
* Shader linker. Currently:
*
* 1. The last attached vertex shader and fragment shader are linked.
* 2. Varying vars in the two shaders are combined so their locations
* agree between the vertex and fragment stages. They're treated as
* vertex program output attribs and as fragment program input attribs.
* 3. The vertex and fragment programs are cloned and modified to update
* src/dst register references so they use the new, linked varying
* storage locations.
*/
void
_slang_link(GLcontext *ctx,
GLhandleARB programObj,
struct gl_shader_program *shProg)
{
const struct gl_vertex_program *vertProg;
const struct gl_fragment_program *fragProg;
GLuint numSamplers = 0;
GLuint i;
_mesa_clear_shader_program_data(ctx, shProg);
/* Initialize LinkStatus to "success". Will be cleared if error. */
shProg->LinkStatus = GL_TRUE;
/* check that all programs compiled successfully */
for (i = 0; i < shProg->NumShaders; i++) {
if (!shProg->Shaders[i]->CompileStatus) {
link_error(shProg, "linking with uncompiled shader\n");
return;
}
}
shProg->Uniforms = _mesa_new_uniform_list();
shProg->Varying = _mesa_new_parameter_list();
/*
* Find the vertex and fragment shaders which define main()
*/
{
struct gl_shader *vertShader, *fragShader;
vertShader = get_main_shader(ctx, shProg, GL_VERTEX_SHADER);
fragShader = get_main_shader(ctx, shProg, GL_FRAGMENT_SHADER);
if (vertShader)
vertProg = vertex_program(vertShader->Program);
if (fragShader)
fragProg = fragment_program(fragShader->Program);
if (!shProg->LinkStatus)
return;
}
#if FEATURE_es2_glsl
/* must have both a vertex and fragment program for ES2 */
if (!vertProg) {
link_error(shProg, "missing vertex shader\n");
return;
}
if (!fragProg) {
link_error(shProg, "missing fragment shader\n");
return;
}
#endif
/*
* Make copies of the vertex/fragment programs now since we'll be
* changing src/dst registers after merging the uniforms and varying vars.
*/
_mesa_reference_vertprog(ctx, &shProg->VertexProgram, NULL);
if (vertProg) {
struct gl_vertex_program *linked_vprog =
vertex_program(_mesa_clone_program(ctx, &vertProg->Base));
shProg->VertexProgram = linked_vprog; /* refcount OK */
ASSERT(shProg->VertexProgram->Base.RefCount == 1);
}
_mesa_reference_fragprog(ctx, &shProg->FragmentProgram, NULL);
if (fragProg) {
struct gl_fragment_program *linked_fprog =
fragment_program(_mesa_clone_program(ctx, &fragProg->Base));
shProg->FragmentProgram = linked_fprog; /* refcount OK */
ASSERT(shProg->FragmentProgram->Base.RefCount == 1);
}
/* link varying vars */
if (shProg->VertexProgram) {
if (!link_varying_vars(shProg, &shProg->VertexProgram->Base))
return;
}
if (shProg->FragmentProgram) {
if (!link_varying_vars(shProg, &shProg->FragmentProgram->Base))
return;
}
/* link uniform vars */
if (shProg->VertexProgram) {
if (!link_uniform_vars(ctx, shProg, &shProg->VertexProgram->Base,
&numSamplers)) {
return;
}
}
if (shProg->FragmentProgram) {
if (!link_uniform_vars(ctx, shProg, &shProg->FragmentProgram->Base,
&numSamplers)) {
return;
}
}
/*_mesa_print_uniforms(shProg->Uniforms);*/
if (shProg->VertexProgram) {
if (!_slang_resolve_attributes(shProg, &vertProg->Base,
&shProg->VertexProgram->Base)) {
return;
}
}
if (shProg->VertexProgram) {
_slang_update_inputs_outputs(&shProg->VertexProgram->Base);
_slang_count_temporaries(&shProg->VertexProgram->Base);
if (!(shProg->VertexProgram->Base.OutputsWritten & (1 << VERT_RESULT_HPOS))) {
/* the vertex program did not compute a vertex position */
link_error(shProg,
"gl_Position was not written by vertex shader\n");
return;
}
}
if (shProg->FragmentProgram) {
_slang_count_temporaries(&shProg->FragmentProgram->Base);
_slang_update_inputs_outputs(&shProg->FragmentProgram->Base);
}
/* Check that all the varying vars needed by the fragment shader are
* actually produced by the vertex shader.
*/
if (shProg->FragmentProgram) {
const GLbitfield varyingRead
= shProg->FragmentProgram->Base.InputsRead >> FRAG_ATTRIB_VAR0;
const GLbitfield varyingWritten = shProg->VertexProgram ?
shProg->VertexProgram->Base.OutputsWritten >> VERT_RESULT_VAR0 : 0x0;
if ((varyingRead & varyingWritten) != varyingRead) {
link_error(shProg,
"Fragment program using varying vars not written by vertex shader\n");
return;
}
}
/* check that gl_FragColor and gl_FragData are not both written to */
if (shProg->FragmentProgram) {
GLbitfield outputsWritten = shProg->FragmentProgram->Base.OutputsWritten;
if ((outputsWritten & ((1 << FRAG_RESULT_COLOR))) &&
(outputsWritten >= (1 << FRAG_RESULT_DATA0))) {
link_error(shProg, "Fragment program cannot write both gl_FragColor"
" and gl_FragData[].\n");
return;
}
}
if (fragProg && shProg->FragmentProgram) {
/* Compute initial program's TexturesUsed info */
_mesa_update_shader_textures_used(&shProg->FragmentProgram->Base);
/* notify driver that a new fragment program has been compiled/linked */
ctx->Driver.ProgramStringNotify(ctx, GL_FRAGMENT_PROGRAM_ARB,
&shProg->FragmentProgram->Base);
if (ctx->Shader.Flags & GLSL_DUMP) {
_mesa_printf("Mesa pre-link fragment program:\n");
_mesa_print_program(&fragProg->Base);
_mesa_print_program_parameters(ctx, &fragProg->Base);
_mesa_printf("Mesa post-link fragment program:\n");
_mesa_print_program(&shProg->FragmentProgram->Base);
_mesa_print_program_parameters(ctx, &shProg->FragmentProgram->Base);
}
}
if (vertProg && shProg->VertexProgram) {
/* Compute initial program's TexturesUsed info */
_mesa_update_shader_textures_used(&shProg->VertexProgram->Base);
/* notify driver that a new vertex program has been compiled/linked */
ctx->Driver.ProgramStringNotify(ctx, GL_VERTEX_PROGRAM_ARB,
&shProg->VertexProgram->Base);
if (ctx->Shader.Flags & GLSL_DUMP) {
_mesa_printf("Mesa pre-link vertex program:\n");
_mesa_print_program(&vertProg->Base);
_mesa_print_program_parameters(ctx, &vertProg->Base);
_mesa_printf("Mesa post-link vertex program:\n");
_mesa_print_program(&shProg->VertexProgram->Base);
_mesa_print_program_parameters(ctx, &shProg->VertexProgram->Base);
}
}
if (ctx->Shader.Flags & GLSL_DUMP) {
_mesa_printf("Varying vars:\n");
_mesa_print_parameter_list(shProg->Varying);
if (shProg->InfoLog) {
_mesa_printf("Info Log: %s\n", shProg->InfoLog);
}
}
shProg->LinkStatus = (shProg->VertexProgram || shProg->FragmentProgram);
}
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