i965: Store uniform constant values in a gl_constant_value instead of float

The brw_stage_prog_data struct previously contained an array of float pointers
to the values of parameters. These were then copied into a batch buffer to
upload the values using a regular assignment. However the float values were
also being overloaded to store integer values for integer uniforms. This can
break if x87 floating-point registers are used to do the assignment because
the fst instruction tries to fix up invalid float values. If an integer
constant happened to look like an invalid float value then it would get
altered when it was copied into the batch buffer.

This patch changes the pointers to be gl_constant_value instead so that the
assignment should end up copying without any alteration. This also makes it
more obvious that the values being stored here are overloaded for multiple
types.

There are some static asserts where the values are uploaded to ensure that the
size of gl_constant_value is the same as a float.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=81150
Reviewed-by: Kenneth Graunke <[email protected]>

13 files changed, 55 insertions, 42 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index 1bbcf469757..157a605365c 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -41,6 +41,7 @@
 #include "main/mtypes.h"
 #include "brw_structs.h"
 #include "intel_aub.h"
+#include "program/prog_parameter.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -309,8 +310,8 @@ struct brw_stage_prog_data {
     * These must be the last fields of the struct (see
     * brw_stage_prog_data_compare()).
     */
-   const float **param;
-   const float **pull_param;
+   const gl_constant_value **param;
+   const gl_constant_value **pull_param;
 };
 
 /* Data about a particular attempt to compile a program.  Note that
diff --git a/src/mesa/drivers/dri/i965/brw_curbe.c b/src/mesa/drivers/dri/i965/brw_curbe.c
index 02eda5f743d..1a828edeb96 100644
--- a/src/mesa/drivers/dri/i965/brw_curbe.c
+++ b/src/mesa/drivers/dri/i965/brw_curbe.c
@@ -196,7 +196,7 @@ brw_upload_constant_buffer(struct brw_context *brw)
    /* BRW_NEW_CURBE_OFFSETS */
    const GLuint sz = brw->curbe.total_size;
    const GLuint bufsz = sz * 16 * sizeof(GLfloat);
-   GLfloat *buf;
+   gl_constant_value *buf;
    GLuint i;
    gl_clip_plane *clip_planes;
 
@@ -207,6 +207,8 @@ brw_upload_constant_buffer(struct brw_context *brw)
    buf = intel_upload_space(brw, bufsz, 64,
                             &brw->curbe.curbe_bo, &brw->curbe.curbe_offset);
 
+   STATIC_ASSERT(sizeof(gl_constant_value) == sizeof(float));
+
    /* fragment shader constants */
    if (brw->curbe.wm_size) {
       /* BRW_NEW_CURBE_OFFSETS */
@@ -226,10 +228,10 @@ brw_upload_constant_buffer(struct brw_context *brw)
       /* If any planes are going this way, send them all this way:
        */
       for (i = 0; i < 6; i++) {
-	 buf[offset + i * 4 + 0] = fixed_plane[i][0];
-	 buf[offset + i * 4 + 1] = fixed_plane[i][1];
-	 buf[offset + i * 4 + 2] = fixed_plane[i][2];
-	 buf[offset + i * 4 + 3] = fixed_plane[i][3];
+	 buf[offset + i * 4 + 0].f = fixed_plane[i][0];
+	 buf[offset + i * 4 + 1].f = fixed_plane[i][1];
+	 buf[offset + i * 4 + 2].f = fixed_plane[i][2];
+	 buf[offset + i * 4 + 3].f = fixed_plane[i][3];
       }
 
       /* Clip planes: _NEW_TRANSFORM plus _NEW_PROJECTION to get to
@@ -238,10 +240,10 @@ brw_upload_constant_buffer(struct brw_context *brw)
       clip_planes = brw_select_clip_planes(ctx);
       for (j = 0; j < MAX_CLIP_PLANES; j++) {
 	 if (ctx->Transform.ClipPlanesEnabled & (1<<j)) {
-	    buf[offset + i * 4 + 0] = clip_planes[j][0];
-	    buf[offset + i * 4 + 1] = clip_planes[j][1];
-	    buf[offset + i * 4 + 2] = clip_planes[j][2];
-	    buf[offset + i * 4 + 3] = clip_planes[j][3];
+	    buf[offset + i * 4 + 0].f = clip_planes[j][0];
+	    buf[offset + i * 4 + 1].f = clip_planes[j][1];
+	    buf[offset + i * 4 + 2].f = clip_planes[j][2];
+	    buf[offset + i * 4 + 3].f = clip_planes[j][3];
 	    i++;
 	 }
       }
@@ -260,7 +262,7 @@ brw_upload_constant_buffer(struct brw_context *brw)
    if (0) {
       for (i = 0; i < sz*16; i+=4)
 	 fprintf(stderr, "curbe %d.%d: %f %f %f %f\n", i/8, i&4,
-                 buf[i+0], buf[i+1], buf[i+2], buf[i+3]);
+                 buf[i+0].f, buf[i+1].f, buf[i+2].f, buf[i+3].f);
    }
 
    /* Because this provokes an action (ie copy the constants into the
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 35ada42c508..43aee66f410 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -961,7 +961,7 @@ fs_visitor::setup_uniform_values(ir_variable *ir)
          slots *= storage->array_elements;
 
       for (unsigned i = 0; i < slots; i++) {
-         stage_prog_data->param[uniforms++] = &storage->storage[i].f;
+         stage_prog_data->param[uniforms++] = &storage->storage[i];
       }
    }
 
@@ -1000,7 +1000,7 @@ fs_visitor::setup_builtin_uniform_values(ir_variable *ir)
 	 last_swiz = swiz;
 
          stage_prog_data->param[uniforms++] =
-            &fp->Base.Parameters->ParameterValues[index][swiz].f;
+            &fp->Base.Parameters->ParameterValues[index][swiz];
       }
    }
 }
@@ -1794,7 +1794,7 @@ fs_visitor::move_uniform_array_access_to_pull_constants()
           * add it.
           */
          if (pull_constant_loc[uniform] == -1) {
-            const float **values = &stage_prog_data->param[uniform];
+            const gl_constant_value **values = &stage_prog_data->param[uniform];
 
             assert(param_size[uniform]);
 
diff --git a/src/mesa/drivers/dri/i965/brw_fs_fp.cpp b/src/mesa/drivers/dri/i965/brw_fs_fp.cpp
index 8d07be2ee17..98df29947ef 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_fp.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_fp.cpp
@@ -583,7 +583,7 @@ fs_visitor::setup_fp_regs()
            p < prog->Parameters->NumParameters; p++) {
          for (unsigned int i = 0; i < 4; i++) {
             stage_prog_data->param[uniforms++] =
-               &prog->Parameters->ParameterValues[p][i].f;
+               &prog->Parameters->ParameterValues[p][i];
          }
       }
    }
diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index c16401b649b..2d5f18d448c 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -1639,7 +1639,7 @@ fs_visitor::rescale_texcoord(ir_texture *ir, fs_reg coordinate,
       /* Try to find existing copies of the texrect scale uniforms. */
       for (unsigned i = 0; i < uniforms; i++) {
          if (stage_prog_data->param[i] ==
-             &prog->Parameters->ParameterValues[index][0].f) {
+             &prog->Parameters->ParameterValues[index][0]) {
             scale_x = fs_reg(UNIFORM, i);
             scale_y = fs_reg(UNIFORM, i + 1);
             break;
@@ -1652,9 +1652,9 @@ fs_visitor::rescale_texcoord(ir_texture *ir, fs_reg coordinate,
          scale_y = fs_reg(UNIFORM, uniforms + 1);
 
          stage_prog_data->param[uniforms++] =
-            &prog->Parameters->ParameterValues[index][0].f;
+            &prog->Parameters->ParameterValues[index][0];
          stage_prog_data->param[uniforms++] =
-            &prog->Parameters->ParameterValues[index][1].f;
+            &prog->Parameters->ParameterValues[index][1];
       }
    }
 
diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
index b572b611fd6..5f8f39971b9 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
@@ -667,7 +667,7 @@ vec4_visitor::move_push_constants_to_pull_constants()
       pull_constant_loc[i / 4] = -1;
 
       if (i >= max_uniform_components) {
-	 const float **values = &stage_prog_data->param[i];
+	 const gl_constant_value **values = &stage_prog_data->param[i];
 
 	 /* Try to find an existing copy of this uniform in the pull
 	  * constants if it was part of an array access already.
@@ -1490,10 +1490,10 @@ vec4_visitor::setup_uniforms(int reg)
       this->uniform_vector_size[this->uniforms] = 1;
 
       stage_prog_data->param =
-         reralloc(NULL, stage_prog_data->param, const float *, 4);
+         reralloc(NULL, stage_prog_data->param, const gl_constant_value *, 4);
       for (unsigned int i = 0; i < 4; i++) {
 	 unsigned int slot = this->uniforms * 4 + i;
-	 static float zero = 0.0;
+	 static gl_constant_value zero = { .f = 0.0 };
 	 stage_prog_data->param[slot] = &zero;
       }
 
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_gs.c b/src/mesa/drivers/dri/i965/brw_vec4_gs.c
index 64282916009..8daa555b532 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_gs.c
+++ b/src/mesa/drivers/dri/i965/brw_vec4_gs.c
@@ -65,9 +65,9 @@ do_gs_prog(struct brw_context *brw,
    param_count += MAX_CLIP_PLANES * 4;
 
    c.prog_data.base.base.param =
-      rzalloc_array(NULL, const float *, param_count);
+      rzalloc_array(NULL, const gl_constant_value *, param_count);
    c.prog_data.base.base.pull_param =
-      rzalloc_array(NULL, const float *, param_count);
+      rzalloc_array(NULL, const gl_constant_value *, param_count);
    /* Setting nr_params here NOT to the size of the param and pull_param
     * arrays, but to the number of uniform components vec4_visitor
     * needs. vec4_visitor::setup_uniforms() will set it back to a proper value.
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index 1b468502616..4863cae3618 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -691,11 +691,11 @@ vec4_visitor::setup_uniform_values(ir_variable *ir)
 
          int i;
          for (i = 0; i < uniform_vector_size[uniforms]; i++) {
-            stage_prog_data->param[uniforms * 4 + i] = &components->f;
+            stage_prog_data->param[uniforms * 4 + i] = components;
             components++;
          }
          for (; i < 4; i++) {
-            static float zero = 0;
+            static gl_constant_value zero = { .f = 0.0 };
             stage_prog_data->param[uniforms * 4 + i] = &zero;
          }
 
@@ -715,7 +715,8 @@ vec4_visitor::setup_uniform_clipplane_values()
       this->userplane[i] = dst_reg(UNIFORM, this->uniforms);
       this->userplane[i].type = BRW_REGISTER_TYPE_F;
       for (int j = 0; j < 4; ++j) {
-         stage_prog_data->param[this->uniforms * 4 + j] = &clip_planes[i][j];
+         stage_prog_data->param[this->uniforms * 4 + j] =
+            (gl_constant_value *) &clip_planes[i][j];
       }
       ++this->uniforms;
    }
@@ -739,7 +740,8 @@ vec4_visitor::setup_builtin_uniform_values(ir_variable *ir)
        */
       int index = _mesa_add_state_reference(this->prog->Parameters,
 					    (gl_state_index *)slots[i].tokens);
-      float *values = &this->prog->Parameters->ParameterValues[index][0].f;
+      gl_constant_value *values =
+         &this->prog->Parameters->ParameterValues[index][0];
 
       assert(this->uniforms < uniform_array_size);
       this->uniform_vector_size[this->uniforms] = 0;
@@ -3309,7 +3311,8 @@ vec4_visitor::move_uniform_array_access_to_pull_constants()
 	  * add it.
 	  */
 	 if (pull_constant_loc[uniform] == -1) {
-	    const float **values = &stage_prog_data->param[uniform * 4];
+	    const gl_constant_value **values =
+               &stage_prog_data->param[uniform * 4];
 
 	    pull_constant_loc[uniform] = stage_prog_data->nr_pull_params / 4;
 
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_vp.cpp b/src/mesa/drivers/dri/i965/brw_vec4_vp.cpp
index f88a3718301..85f2de577fc 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_vp.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_vp.cpp
@@ -401,7 +401,7 @@ vec4_vs_visitor::emit_program_code()
       unsigned i;
       for (i = 0; i < params->NumParameters * 4; i++) {
          stage_prog_data->pull_param[i] =
-            &params->ParameterValues[i / 4][i % 4].f;
+            &params->ParameterValues[i / 4][i % 4];
       }
       stage_prog_data->nr_pull_params = i;
    }
@@ -432,7 +432,7 @@ vec4_vs_visitor::setup_vp_regs()
       this->uniform_vector_size[this->uniforms] = components;
       for (unsigned i = 0; i < 4; i++) {
          stage_prog_data->param[this->uniforms * 4 + i] = i >= components
-            ? 0 : &plist->ParameterValues[p][i].f;
+            ? 0 : &plist->ParameterValues[p][i];
       }
       this->uniforms++; /* counted in vec4 units */
    }
diff --git a/src/mesa/drivers/dri/i965/brw_vs.c b/src/mesa/drivers/dri/i965/brw_vs.c
index 19b1d3b1a12..4574c3ececa 100644
--- a/src/mesa/drivers/dri/i965/brw_vs.c
+++ b/src/mesa/drivers/dri/i965/brw_vs.c
@@ -233,8 +233,10 @@ do_vs_prog(struct brw_context *brw,
     */
    param_count += c.key.base.nr_userclip_plane_consts * 4;
 
-   stage_prog_data->param = rzalloc_array(NULL, const float *, param_count);
-   stage_prog_data->pull_param = rzalloc_array(NULL, const float *, param_count);
+   stage_prog_data->param =
+      rzalloc_array(NULL, const gl_constant_value *, param_count);
+   stage_prog_data->pull_param =
+      rzalloc_array(NULL, const gl_constant_value *, param_count);
 
    /* Setting nr_params here NOT to the size of the param and pull_param
     * arrays, but to the number of uniform components vec4_visitor
diff --git a/src/mesa/drivers/dri/i965/brw_vs_surface_state.c b/src/mesa/drivers/dri/i965/brw_vs_surface_state.c
index ef4a77a63ed..1cc96cf683f 100644
--- a/src/mesa/drivers/dri/i965/brw_vs_surface_state.c
+++ b/src/mesa/drivers/dri/i965/brw_vs_surface_state.c
@@ -76,8 +76,10 @@ brw_upload_pull_constants(struct brw_context *brw,
    uint32_t size = prog_data->nr_pull_params * 4;
    drm_intel_bo *const_bo = NULL;
    uint32_t const_offset;
-   float *constants = intel_upload_space(brw, size, 64,
-                                         &const_bo, &const_offset);
+   gl_constant_value *constants = intel_upload_space(brw, size, 64,
+                                                     &const_bo, &const_offset);
+
+   STATIC_ASSERT(sizeof(gl_constant_value) == sizeof(float));
 
    for (i = 0; i < prog_data->nr_pull_params; i++) {
       constants[i] = *prog_data->pull_param[i];
@@ -85,9 +87,9 @@ brw_upload_pull_constants(struct brw_context *brw,
 
    if (0) {
       for (i = 0; i < ALIGN(prog_data->nr_pull_params, 4) / 4; i++) {
-	 float *row = &constants[i * 4];
+	 const gl_constant_value *row = &constants[i * 4];
 	 fprintf(stderr, "const surface %3d: %4.3f %4.3f %4.3f %4.3f\n",
-                 i, row[0], row[1], row[2], row[3]);
+                 i, row[0].f, row[1].f, row[2].f, row[3].f);
       }
    }
 
diff --git a/src/mesa/drivers/dri/i965/brw_wm.c b/src/mesa/drivers/dri/i965/brw_wm.c
index 6e068d381b7..2e3cd4bb2cc 100644
--- a/src/mesa/drivers/dri/i965/brw_wm.c
+++ b/src/mesa/drivers/dri/i965/brw_wm.c
@@ -169,9 +169,10 @@ bool do_wm_prog(struct brw_context *brw,
    }
    /* The backend also sometimes adds params for texture size. */
    param_count += 2 * ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits;
-   prog_data.base.param = rzalloc_array(NULL, const float *, param_count);
+   prog_data.base.param =
+      rzalloc_array(NULL, const gl_constant_value *, param_count);
    prog_data.base.pull_param =
-   rzalloc_array(NULL, const float *, param_count);
+      rzalloc_array(NULL, const gl_constant_value *, param_count);
    prog_data.base.nr_params = param_count;
 
    prog_data.barycentric_interp_modes =
diff --git a/src/mesa/drivers/dri/i965/gen6_vs_state.c b/src/mesa/drivers/dri/i965/gen6_vs_state.c
index 905e123837f..77f566cd356 100644
--- a/src/mesa/drivers/dri/i965/gen6_vs_state.c
+++ b/src/mesa/drivers/dri/i965/gen6_vs_state.c
@@ -67,13 +67,15 @@ gen6_upload_push_constants(struct brw_context *brw,
    if (prog_data->nr_params == 0) {
       stage_state->push_const_size = 0;
    } else {
-      float *param;
+      gl_constant_value *param;
       int i;
 
       param = brw_state_batch(brw, type,
-			      prog_data->nr_params * sizeof(float),
+			      prog_data->nr_params * sizeof(gl_constant_value),
 			      32, &stage_state->push_const_offset);
 
+      STATIC_ASSERT(sizeof(gl_constant_value) == sizeof(float));
+
       /* _NEW_PROGRAM_CONSTANTS
        *
        * Also _NEW_TRANSFORM -- we may reference clip planes other than as a
@@ -91,7 +93,7 @@ gen6_upload_push_constants(struct brw_context *brw,
 	    if ((i & 7) == 0)
 	       fprintf(stderr, "g%d: ",
                        prog_data->dispatch_grf_start_reg + i / 8);
-	    fprintf(stderr, "%8f ", param[i]);
+	    fprintf(stderr, "%8f ", param[i].f);
 	    if ((i & 7) == 7)
 	       fprintf(stderr, "\n");
 	 }