From: Marek Olšák Date: Sun, 10 May 2020 00:57:25 +0000 (-0400) Subject: glsl: lower the precision of imageLoad X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0c0803c32fd5b1c6cc037372990d2b6f84762135;p=mesa.git glsl: lower the precision of imageLoad Acked-by: Alyssa Rosenzweig Reviewed-by: Rob Clark Part-of: --- diff --git a/src/compiler/glsl/lower_builtins.cpp b/src/compiler/glsl/lower_builtins.cpp index e7130df7ac6..7b5ac204e65 100644 --- a/src/compiler/glsl/lower_builtins.cpp +++ b/src/compiler/glsl/lower_builtins.cpp @@ -52,7 +52,10 @@ lower_builtins(exec_list *instructions) ir_visitor_status lower_builtins_visitor::visit_leave(ir_call *ir) { - if (!ir->callee->is_builtin()) + /* lower_precision() also inlines some intrinsics, which can't be inlined + * further. + */ + if (!ir->callee->is_builtin() || ir->callee->is_intrinsic()) return visit_continue; ir->generate_inline(ir); diff --git a/src/compiler/glsl/lower_precision.cpp b/src/compiler/glsl/lower_precision.cpp index b410e3290a2..faa990703e6 100644 --- a/src/compiler/glsl/lower_precision.cpp +++ b/src/compiler/glsl/lower_precision.cpp @@ -163,6 +163,7 @@ find_lowerable_rvalues_visitor::can_lower_type(const glsl_type *type) const */ case GLSL_TYPE_BOOL: case GLSL_TYPE_SAMPLER: + case GLSL_TYPE_IMAGE: return true; case GLSL_TYPE_FLOAT: @@ -416,6 +417,38 @@ static bool is_lowerable_builtin(ir_call *ir, const struct set *lowerable_rvalues) { + /* The intrinsic call is inside the wrapper imageLoad function that will + * be inlined. We have to handle both of them. + */ + if (ir->callee->intrinsic_id == ir_intrinsic_image_load || + (ir->callee->is_builtin() && + !strcmp(ir->callee_name(), "imageLoad"))) { + ir_rvalue *param = (ir_rvalue*)ir->actual_parameters.get_head(); + ir_variable *resource = param->variable_referenced(); + + assert(ir->callee->return_precision == GLSL_PRECISION_NONE); + assert(resource->type->without_array()->is_image()); + + /* GLSL ES 3.20 requires that images have a precision modifier, but if + * you set one, it doesn't do anything, because all intrinsics are + * defined with highp. This seems to be a spec bug. + * + * In theory we could set the return value to mediump if the image + * format has a lower precision. This appears to be the most sensible + * thing to do. + */ + const struct util_format_description *desc = + util_format_description(resource->data.image_format); + unsigned i = + util_format_get_first_non_void_channel(resource->data.image_format); + + if (desc->channel[i].pure_integer || + desc->channel[i].type == UTIL_FORMAT_TYPE_FLOAT) + return desc->channel[i].size <= 16; + else + return desc->channel[i].size <= 10; /* unorm/snorm */ + } + if (!ir->callee->is_builtin()) return false; @@ -728,17 +761,28 @@ find_precision_visitor::visit_enter(ir_call *ir) { ir_rvalue_enter_visitor::visit_enter(ir); + ir_variable *return_var = + ir->return_deref ? ir->return_deref->variable_referenced() : NULL; + + /* Don't do anything for image_load here. We have only changed the return + * value to mediump/lowp, so that following instructions can use reduced + * precision. + * + * The return value type of the intrinsic itself isn't changed here, but + * can be changed in NIR if all users use the *2*mp opcode. + */ + if (ir->callee->intrinsic_id == ir_intrinsic_image_load) + return visit_continue; + /* If this is a call to a builtin and the find_lowerable_rvalues_visitor * overrode the precision of the temporary return variable, then we can * replace the builtin implementation with a lowered version. */ if (!ir->callee->is_builtin() || - ir->return_deref == NULL || - (ir->return_deref->variable_referenced()->data.precision != - GLSL_PRECISION_MEDIUM && - ir->return_deref->variable_referenced()->data.precision != - GLSL_PRECISION_LOW)) + return_var == NULL || + (return_var->data.precision != GLSL_PRECISION_MEDIUM && + return_var->data.precision != GLSL_PRECISION_LOW)) return visit_continue; ir->callee = map_builtin(ir->callee); diff --git a/src/compiler/glsl/tests/lower_precision_test.py b/src/compiler/glsl/tests/lower_precision_test.py index 3626d8d2a4b..45175262878 100644 --- a/src/compiler/glsl/tests/lower_precision_test.py +++ b/src/compiler/glsl/tests/lower_precision_test.py @@ -971,6 +971,78 @@ TESTS = [ } """, r'\(expression +u16vec4 +/.*\(tex +u16vec4 +'), + Test("f32 image array", + """ + #version 320 es + precision mediump float; + + layout(rgba16f) readonly uniform mediump image2D img[2]; + // highp shouldn't affect the return value of imageLoad + uniform highp ivec2 coord; + uniform float divisor; + + out highp vec4 color; + + void main() + { + color = imageLoad(img[1], coord) / divisor; + } + """, + r'\(expression +f16vec4 +/'), + Test("f32 image load", + """ + #version 310 es + precision mediump float; + precision mediump int; + + layout(rgba16f) readonly uniform mediump image2D img; + uniform ivec2 coord; + uniform float divisor; + + out highp vec4 color; + + void main() + { + color = imageLoad(img, coord) / divisor; + } + """, + r'\(expression +f16vec4 +/'), + Test("i32 image load", + """ + #version 310 es + precision mediump float; + precision mediump int; + + layout(rgba16i) readonly uniform mediump iimage2D img; + uniform ivec2 coord; + uniform int divisor; + + out highp ivec4 color; + + void main() + { + color = imageLoad(img, coord) / divisor; + } + """, + r'\(expression +i16vec4 +/'), + Test("u32 image load", + """ + #version 310 es + precision mediump float; + precision mediump int; + + layout(rgba16ui) readonly uniform mediump uimage2D img; + uniform ivec2 coord; + uniform uint divisor; + + out highp uvec4 color; + + void main() + { + color = imageLoad(img, coord) / divisor; + } + """, + r'\(expression +u16vec4 +/'), Test("f32 expression in lvalue", """ uniform mediump float a, b;