[Mesa-dev] [PATCH v3 1/3] glsl: Add new barrier functions for compute shaders

[Jordan Justen]

When these functions are called in GLSL code, we create an intrinsic
function call:

 * groupMemoryBarrier => __intrinsic_group_memory_barrier
 * memoryBarrierAtomicCounter => __intrinsic_memory_barrier_atomic_counter
 * memoryBarrierBuffer => __intrinsic_memory_barrier_buffer
 * memoryBarrierImage => __intrinsic_memory_barrier_image
 * memoryBarrierShared => __intrinsic_memory_barrier_shared

v2:
 * Consolidate with memoryBarrier function/intrinsic creation (curro)

v3:
 * Instead of add_memory_barrier_function, add an intrinsic_name
   parameter to _memory_barrier (curro)

Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
Cc: Francisco Jerez <currojerez at riseup.net>
---
 src/glsl/builtin_functions.cpp | 55 +++++++++++++++++++++++++++++++++++++-----
 1 file changed, 49 insertions(+), 6 deletions(-)

diff --git a/src/glsl/builtin_functions.cpp b/src/glsl/builtin_functions.cpp
index 509a57b..1349444 100644
--- a/src/glsl/builtin_functions.cpp
+++ b/src/glsl/builtin_functions.cpp
@@ -459,9 +459,15 @@ fp64(const _mesa_glsl_parse_state *state)
 }
 
 static bool
+compute_shader(const _mesa_glsl_parse_state *state)
+{
+   return state->stage == MESA_SHADER_COMPUTE;
+}
+
+static bool
 barrier_supported(const _mesa_glsl_parse_state *state)
 {
-   return state->stage == MESA_SHADER_COMPUTE ||
+   return compute_shader(state) ||
           state->stage == MESA_SHADER_TESS_CTRL;
 }
 
@@ -785,8 +791,8 @@ private:
 
    ir_function_signature *_memory_barrier_intrinsic(
       builtin_available_predicate avail);
-   ir_function_signature *_memory_barrier(
-      builtin_available_predicate avail);
+   ir_function_signature *_memory_barrier(const char *intrinsic_name,
+                                          builtin_available_predicate avail);
 
    ir_function_signature *_shader_clock_intrinsic(builtin_available_predicate avail,
                                                   const glsl_type *type);
@@ -963,6 +969,21 @@ builtin_builder::create_intrinsics()
    add_function("__intrinsic_memory_barrier",
                 _memory_barrier_intrinsic(shader_image_load_store),
                 NULL);
+   add_function("__intrinsic_group_memory_barrier",
+                _memory_barrier_intrinsic(compute_shader),
+                NULL);
+   add_function("__intrinsic_memory_barrier_atomic_counter",
+                _memory_barrier_intrinsic(compute_shader),
+                NULL);
+   add_function("__intrinsic_memory_barrier_buffer",
+                _memory_barrier_intrinsic(compute_shader),
+                NULL);
+   add_function("__intrinsic_memory_barrier_image",
+                _memory_barrier_intrinsic(compute_shader),
+                NULL);
+   add_function("__intrinsic_memory_barrier_shared",
+                _memory_barrier_intrinsic(compute_shader),
+                NULL);
 
    add_function("__intrinsic_shader_clock",
                 _shader_clock_intrinsic(shader_clock,
@@ -2754,7 +2775,28 @@ builtin_builder::create_builtins()
    add_image_functions(true);
 
    add_function("memoryBarrier",
-                _memory_barrier(shader_image_load_store),
+                _memory_barrier("__intrinsic_memory_barrier",
+                                shader_image_load_store),
+                NULL);
+   add_function("groupMemoryBarrier",
+                _memory_barrier("__intrinsic_group_memory_barrier",
+                                compute_shader),
+                NULL);
+   add_function("memoryBarrierAtomicCounter",
+                _memory_barrier("__intrinsic_memory_barrier_atomic_counter",
+                                compute_shader),
+                NULL);
+   add_function("memoryBarrierBuffer",
+                _memory_barrier("__intrinsic_memory_barrier_buffer",
+                                compute_shader),
+                NULL);
+   add_function("memoryBarrierImage",
+                _memory_barrier("__intrinsic_memory_barrier_image",
+                                compute_shader),
+                NULL);
+   add_function("memoryBarrierShared",
+                _memory_barrier("__intrinsic_memory_barrier_shared",
+                                compute_shader),
                 NULL);
 
    add_function("clock2x32ARB",
@@ -5264,10 +5306,11 @@ builtin_builder::_memory_barrier_intrinsic(builtin_available_predicate avail)
 }
 
 ir_function_signature *
-builtin_builder::_memory_barrier(builtin_available_predicate avail)
+builtin_builder::_memory_barrier(const char *intrinsic_name,
+                                 builtin_available_predicate avail)
 {
    MAKE_SIG(glsl_type::void_type, avail, 0);
-   body.emit(call(shader->symbols->get_function("__intrinsic_memory_barrier"),
+   body.emit(call(shader->symbols->get_function(intrinsic_name),
                   NULL, sig->parameters));
    return sig;
 }
-- 
2.6.2