[Mesa-dev] [PATCH V2 5/7] i965: relax brw_texture_offset assert

[Chris Forbes]

Some texturing ops are about to have nonconstant offset support; the
offset in the header in these cases should be zero.

Signed-off-by: Chris Forbes <chrisf at ijw.co.nz>
Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>
---
 src/mesa/drivers/dri/i965/brw_fs_visitor.cpp   | 2 +-
 src/mesa/drivers/dri/i965/brw_shader.cpp       | 9 +++++++--
 src/mesa/drivers/dri/i965/brw_shader.h         | 2 +-
 src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp | 2 +-
 4 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index e659203..3fde443 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -1595,7 +1595,7 @@ fs_visitor::visit(ir_texture *ir)
    }
 
    if (ir->offset != NULL && ir->op != ir_txf)
-      inst->texture_offset = brw_texture_offset(ir->offset->as_constant());
+      inst->texture_offset = brw_texture_offset(ctx, ir->offset->as_constant());
 
    if (ir->op == ir_tg4)
       inst->texture_offset |= gather_channel(ir, sampler) << 16; // M0.2:16-17
diff --git a/src/mesa/drivers/dri/i965/brw_shader.cpp b/src/mesa/drivers/dri/i965/brw_shader.cpp
index 6b37f58..5da1b0f 100644
--- a/src/mesa/drivers/dri/i965/brw_shader.cpp
+++ b/src/mesa/drivers/dri/i965/brw_shader.cpp
@@ -368,9 +368,14 @@ brw_math_function(enum opcode op)
 }
 
 uint32_t
-brw_texture_offset(ir_constant *offset)
+brw_texture_offset(struct gl_context *ctx, ir_constant *offset)
 {
-   assert(offset != NULL);
+   /* If the driver does not support GL_ARB_gpu_shader5, the offset
+    * must be constant.
+    */
+   assert(offset != NULL || ctx->Extensions.ARB_gpu_shader5);
+
+   if (!offset) return 0;  /* nonconstant offset; caller will handle it. */
 
    signed char offsets[3];
    for (unsigned i = 0; i < offset->type->vector_elements; i++)
diff --git a/src/mesa/drivers/dri/i965/brw_shader.h b/src/mesa/drivers/dri/i965/brw_shader.h
index 4dbd38d..3feee69 100644
--- a/src/mesa/drivers/dri/i965/brw_shader.h
+++ b/src/mesa/drivers/dri/i965/brw_shader.h
@@ -72,7 +72,7 @@ public:
    void dump_instructions();
 };
 
-uint32_t brw_texture_offset(ir_constant *offset);
+uint32_t brw_texture_offset(struct gl_context *ctx, ir_constant *offset);
 
 #endif /* __cplusplus */
 
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index 0cf8277..bd9c9e9 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -2286,7 +2286,7 @@ vec4_visitor::visit(ir_texture *ir)
    inst->shadow_compare = ir->shadow_comparitor != NULL;
 
    if (use_texture_offset)
-      inst->texture_offset = brw_texture_offset(ir->offset->as_constant());
+      inst->texture_offset = brw_texture_offset(ctx, ir->offset->as_constant());
 
    /* Stuff the channel select bits in the top of the texture offset */
    if (ir->op == ir_tg4)
-- 
1.8.4