[Mesa-dev] [PATCH 04/13] i965 vs: Make first_non_payload_grf an explicit function argument.

[Paul Berry]

Previously, vec4_visitor::setup_payload() stored the location of the
first non-payload GRF in vec4_visitor::first_non_payload_grf, where it
was later picked up by the register allocator.  Now setup_payload()
returns the location to the caller (vec4_visitor::run()), which passes
it directly to the register allocator.

This helps pave the way for separating the IR visiting parts of
vec4_visitor (which include setup_payload()) and the code generation
parts (which include the register allocator), by making the data flow
between the two parts more explicit.
---
 src/mesa/drivers/dri/i965/brw_vec4.h               |    7 +++----
 src/mesa/drivers/dri/i965/brw_vec4_emit.cpp        |    8 ++++----
 .../drivers/dri/i965/brw_vec4_reg_allocate.cpp     |   10 +++++-----
 3 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_vec4.h b/src/mesa/drivers/dri/i965/brw_vec4.h
index 9c4495a..c546235 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.h
+++ b/src/mesa/drivers/dri/i965/brw_vec4.h
@@ -321,7 +321,6 @@ public:
    int *virtual_grf_sizes;
    int virtual_grf_count;
    int virtual_grf_array_size;
-   int first_non_payload_grf;
    int *virtual_grf_def;
    int *virtual_grf_use;
    dst_reg userplane[MAX_CLIP_PLANES];
@@ -389,9 +388,9 @@ public:
    void setup_builtin_uniform_values(ir_variable *ir);
    int setup_attributes(int payload_reg);
    int setup_uniforms(int payload_reg);
-   void setup_payload();
-   int reg_allocate_trivial();
-   int reg_allocate();
+   int setup_payload();
+   int reg_allocate_trivial(int first_non_payload_grf);
+   int reg_allocate(int first_non_payload_grf);
    unsigned move_grf_array_access_to_scratch();
    void move_uniform_array_access_to_pull_constants();
    void move_push_constants_to_pull_constants();
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
index 061d487..3219fe4 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
@@ -127,7 +127,7 @@ vec4_visitor::setup_uniforms(int reg)
    return reg;
 }
 
-void
+int
 vec4_visitor::setup_payload(void)
 {
    int reg = 0;
@@ -142,7 +142,7 @@ vec4_visitor::setup_payload(void)
 
    reg = setup_attributes(reg);
 
-   this->first_non_payload_grf = reg;
+   return reg;
 }
 
 struct brw_reg
@@ -656,8 +656,8 @@ vec4_visitor::run()
    if (failed)
       return false;
 
-   setup_payload();
-   prog_data->total_grf = reg_allocate();
+   int first_non_payload_grf = setup_payload();
+   prog_data->total_grf = reg_allocate(first_non_payload_grf);
 
    if (failed)
       return false;
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp b/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp
index 7848656..f6db9b4 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp
@@ -42,7 +42,7 @@ assign(int *reg_hw_locations, reg *reg)
 }
 
 int
-vec4_visitor::reg_allocate_trivial()
+vec4_visitor::reg_allocate_trivial(int first_non_payload_grf)
 {
    int hw_reg_mapping[this->virtual_grf_count];
    bool virtual_grf_used[this->virtual_grf_count];
@@ -68,7 +68,7 @@ vec4_visitor::reg_allocate_trivial()
       }
    }
 
-   hw_reg_mapping[0] = this->first_non_payload_grf;
+   hw_reg_mapping[0] = first_non_payload_grf;
    next = hw_reg_mapping[0] + this->virtual_grf_sizes[0];
    for (i = 1; i < this->virtual_grf_count; i++) {
       if (virtual_grf_used[i]) {
@@ -142,10 +142,10 @@ brw_alloc_reg_set_for_classes(struct brw_context *brw,
 }
 
 int
-vec4_visitor::reg_allocate()
+vec4_visitor::reg_allocate(int first_non_payload_grf)
 {
    int hw_reg_mapping[virtual_grf_count];
-   int first_assigned_grf = this->first_non_payload_grf;
+   int first_assigned_grf = first_non_payload_grf;
    int base_reg_count = BRW_MAX_GRF - first_assigned_grf;
    int class_sizes[base_reg_count];
    int class_count = 0;
@@ -154,7 +154,7 @@ vec4_visitor::reg_allocate()
     * register access as a result of broken optimization passes.
     */
    if (0) {
-      return reg_allocate_trivial();
+      return reg_allocate_trivial(first_non_payload_grf);
    }
 
    calculate_live_intervals();
-- 
1.7.6.4