[Mesa-dev] [PATCH 03/50] glsl: Add "built-in" function to do sign(fp64) (v2)

[Dave Airlie]

From: Elie Tournier <tournier.elie at gmail.com>

v2: use mix.

Signed-off-by: Elie Tournier <elie.tournier at collabora.com>
---
 src/compiler/glsl/builtin_float64.h     | 28 ++++++++++++++++++++++++++++
 src/compiler/glsl/builtin_functions.cpp |  4 ++++
 src/compiler/glsl/builtin_functions.h   |  3 +++
 src/compiler/glsl/float64.glsl          |  9 +++++++++
 src/compiler/glsl/glcpp/glcpp-parse.y   |  1 +
 5 files changed, 45 insertions(+)

diff --git a/src/compiler/glsl/builtin_float64.h b/src/compiler/glsl/builtin_float64.h
index 2898fc9..8546048 100644
--- a/src/compiler/glsl/builtin_float64.h
+++ b/src/compiler/glsl/builtin_float64.h
@@ -68,3 +68,31 @@ fneg64(void *mem_ctx, builtin_available_predicate avail)
    sig->replace_parameters(&sig_parameters);
    return sig;
 }
+ir_function_signature *
+fsign64(void *mem_ctx, builtin_available_predicate avail)
+{
+   ir_function_signature *const sig =
+      new(mem_ctx) ir_function_signature(glsl_type::uvec2_type, avail);
+   ir_factory body(&sig->body, mem_ctx);
+   sig->is_defined = true;
+
+   exec_list sig_parameters;
+
+   ir_variable *const r001D = new(mem_ctx) ir_variable(glsl_type::uvec2_type, "a", ir_var_function_in);
+   sig_parameters.push_tail(r001D);
+   ir_variable *const r001E = new(mem_ctx) ir_variable(glsl_type::uvec2_type, "retval", ir_var_auto);
+   body.emit(r001E);
+   body.emit(assign(r001E, body.constant(0u), 0x01));
+
+   ir_expression *const r001F = lshift(swizzle_y(r001D), body.constant(int(1)));
+   ir_expression *const r0020 = bit_or(r001F, swizzle_x(r001D));
+   ir_expression *const r0021 = equal(r0020, body.constant(0u));
+   ir_expression *const r0022 = bit_and(swizzle_y(r001D), body.constant(2147483648u));
+   ir_expression *const r0023 = bit_or(r0022, body.constant(1072693248u));
+   body.emit(assign(r001E, expr(ir_triop_csel, r0021, body.constant(0u), r0023), 0x02));
+
+   body.emit(ret(r001E));
+
+   sig->replace_parameters(&sig_parameters);
+   return sig;
+}
diff --git a/src/compiler/glsl/builtin_functions.cpp b/src/compiler/glsl/builtin_functions.cpp
index 9d88a31..17aa868 100644
--- a/src/compiler/glsl/builtin_functions.cpp
+++ b/src/compiler/glsl/builtin_functions.cpp
@@ -3350,6 +3350,10 @@ builtin_builder::create_builtins()
                 generate_ir::fneg64(mem_ctx, integer_functions_supported),
                 NULL);
 
+   add_function("__builtin_fsign64",
+                generate_ir::fsign64(mem_ctx, integer_functions_supported),
+                NULL);
+
 #undef F
 #undef FI
 #undef FIUD_VEC
diff --git a/src/compiler/glsl/builtin_functions.h b/src/compiler/glsl/builtin_functions.h
index adec424..7954373 100644
--- a/src/compiler/glsl/builtin_functions.h
+++ b/src/compiler/glsl/builtin_functions.h
@@ -73,6 +73,9 @@ fabs64(void *mem_ctx, builtin_available_predicate avail);
 ir_function_signature *
 fneg64(void *mem_ctx, builtin_available_predicate avail);
 
+ir_function_signature *
+fsign64(void *mem_ctx, builtin_available_predicate avail);
+
 }
 
 #endif /* BULITIN_FUNCTIONS_H */
diff --git a/src/compiler/glsl/float64.glsl b/src/compiler/glsl/float64.glsl
index fedf8b7..f8eb1f3 100644
--- a/src/compiler/glsl/float64.glsl
+++ b/src/compiler/glsl/float64.glsl
@@ -51,3 +51,12 @@ fneg64(uvec2 a)
    a.y = mix(t, a.y, is_nan(a));
    return a;
 }
+
+uvec2
+fsign64(uvec2 a)
+{
+   uvec2 retval;
+   retval.x = 0u;
+   retval.y = mix((a.y & 0x80000000u) | 0x3FF00000u, 0u, (a.y << 1 | a.x) == 0u);
+   return retval;
+}
diff --git a/src/compiler/glsl/glcpp/glcpp-parse.y b/src/compiler/glsl/glcpp/glcpp-parse.y
index b9506d8..666543b 100644
--- a/src/compiler/glsl/glcpp/glcpp-parse.y
+++ b/src/compiler/glsl/glcpp/glcpp-parse.y
@@ -2370,6 +2370,7 @@ _glcpp_parser_handle_version_declaration(glcpp_parser_t *parser, intmax_t versio
          add_builtin_define(parser, "__have_builtin_builtin_imod64", 1);
          add_builtin_define(parser, "__have_builtin_builtin_fabs64", 1);
          add_builtin_define(parser, "__have_builtin_builtin_fneg64", 1);
+         add_builtin_define(parser, "__have_builtin_builtin_fsign64", 1);
       }
    }
 
-- 
2.9.5