transform/EmitVertexPointSize: Handle entry point parameters

Generate a new struct that contains members of the original return
type with the point size appended to it, and replace return statements
as necessary.

Fixed: tint:732
Change-Id: I2b5816144d5e95c65baca95dc0c50b4dfdd25ed3
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/48980
Auto-Submit: James Price <jrprice@google.com>
Commit-Queue: James Price <jrprice@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
This commit is contained in:
James Price 2021-04-26 19:37:46 +00:00 committed by Commit Bot service account
parent 9ef328f530
commit 05e16ed1c5
3 changed files with 358 additions and 37 deletions

View File

@ -700,6 +700,9 @@ class ProgramBuilder {
// AST helper methods
//////////////////////////////////////////////////////////////////////////////
/// @return a new unnamed symbol
Symbol Sym() { return Symbols().New(); }
/// @param name the symbol string
/// @return a Symbol with the given name
Symbol Sym(const std::string& name) { return Symbols().Register(name); }

View File

@ -14,10 +14,13 @@
#include "src/transform/emit_vertex_point_size.h"
#include <unordered_map>
#include <utility>
#include "src/ast/assignment_statement.h"
#include "src/program_builder.h"
#include "src/sem/function.h"
#include "src/sem/statement.h"
#include "src/utils/get_or_create.h"
namespace tint {
namespace transform {
@ -26,34 +29,85 @@ EmitVertexPointSize::EmitVertexPointSize() = default;
EmitVertexPointSize::~EmitVertexPointSize() = default;
Output EmitVertexPointSize::Run(const Program* in, const DataMap&) {
if (!in->AST().Functions().HasStage(ast::PipelineStage::kVertex)) {
// If the module doesn't have any vertex stages, then there's nothing to do.
return Output(Program(in->Clone()));
}
ProgramBuilder out;
CloneContext ctx(&out, in);
Symbol pointsize = out.Symbols().New("tint_pointsize");
// Declare the pointsize builtin output variable.
out.Global(pointsize, out.ty.f32(), ast::StorageClass::kOutput, nullptr,
ast::DecorationList{
out.Builtin(ast::Builtin::kPointSize),
});
// Add the pointsize assignment statement to the front of all vertex stages.
ctx.ReplaceAll([&](ast::Function* func) -> ast::Function* {
std::unordered_map<sem::Type*, sem::StructType*> struct_map;
for (auto* func : in->AST().Functions()) {
if (func->pipeline_stage() != ast::PipelineStage::kVertex) {
return nullptr; // Just clone func
continue;
}
return CloneWithStatementsAtStart(&ctx, func,
{
out.Assign(pointsize, 1.0f),
});
auto* sem_func = in->Sem().Get(func);
// Create a struct for the return type that includes a point size member.
auto* new_struct =
utils::GetOrCreate(struct_map, sem_func->ReturnType(), [&]() {
// Gather struct members.
ast::StructMemberList new_struct_members;
if (auto* struct_ty = sem_func->ReturnType()->As<sem::StructType>()) {
for (auto* member : struct_ty->impl()->members()) {
new_struct_members.push_back(ctx.Clone(member));
}
} else {
auto* ret_type = ctx.Clone(sem_func->ReturnType());
auto ret_type_decos = ctx.Clone(func->return_type_decorations());
new_struct_members.push_back(
out.Member("position", ret_type, std::move(ret_type_decos)));
}
// Append a new member for the point size.
new_struct_members.push_back(
out.Member(out.Symbols().New("tint_pointsize"), out.ty.f32(),
{out.Builtin(ast::Builtin::kPointSize)}));
// Create the new output struct.
return out.Structure(out.Sym(), new_struct_members);
});
// Replace return values using new output struct type constructors.
for (auto* ret : sem_func->ReturnStatements()) {
auto* ret_sem = in->Sem().Get(ret);
ast::ExpressionList new_ret_values;
if (auto* struct_ty = sem_func->ReturnType()->As<sem::StructType>()) {
std::function<ast::Expression*()> ret_value = [&]() {
return ctx.Clone(ret->value());
};
if (!ret->value()->Is<ast::IdentifierExpression>()) {
// Capture the original return value in a local temporary.
auto* new_struct_ty = ctx.Clone(struct_ty);
auto* temp = out.Const(out.Sym(), new_struct_ty, ret_value());
ctx.InsertBefore(ret_sem->Block()->statements(), ret, out.Decl(temp));
ret_value = [&, temp]() { return out.Expr(temp); };
}
for (auto* member : struct_ty->impl()->members()) {
auto member_sym = ctx.Clone(member->symbol());
new_ret_values.push_back(out.MemberAccessor(ret_value(), member_sym));
}
} else {
new_ret_values.push_back(ctx.Clone(ret->value()));
}
// Append the point size and replace the return statement.
new_ret_values.push_back(out.Expr(1.f));
ctx.Replace(ret, out.Return(ret->source(),
out.Construct(new_struct, new_ret_values)));
}
// Rewrite the function header with the new return type.
auto func_sym = ctx.Clone(func->symbol());
auto params = ctx.Clone(func->params());
auto* body = ctx.Clone(func->body());
auto decos = ctx.Clone(func->decorations());
auto* new_func = out.create<ast::Function>(
func->source(), func_sym, std::move(params), new_struct, body,
std::move(decos), ast::DecorationList{});
ctx.Replace(func, new_func);
}
ctx.Clone();
return Output(Program(std::move(out)));

View File

@ -29,7 +29,6 @@ fn non_entry_a() {
[[stage(vertex)]]
fn entry() -> [[builtin(position)]] vec4<f32> {
var builtin_assignments_should_happen_before_this : f32;
return vec4<f32>();
}
@ -38,16 +37,19 @@ fn non_entry_b() {
)";
auto* expect = R"(
[[builtin(pointsize)]] var<out> tint_pointsize : f32;
struct tint_symbol {
[[builtin(position)]]
position : vec4<f32>;
[[builtin(pointsize)]]
tint_pointsize : f32;
};
fn non_entry_a() {
}
[[stage(vertex)]]
fn entry() -> [[builtin(position)]] vec4<f32> {
tint_pointsize = 1.0;
var builtin_assignments_should_happen_before_this : f32;
return vec4<f32>();
fn entry() -> tint_symbol {
return tint_symbol(vec4<f32>(), 1.0);
}
fn non_entry_b() {
@ -59,6 +61,255 @@ fn non_entry_b() {
EXPECT_EQ(expect, str(got));
}
TEST_F(EmitVertexPointSizeTest, VertexStageBasic_Struct) {
auto* src = R"(
struct VertexOut {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
};
fn non_entry_a() {
}
[[stage(vertex)]]
fn entry() -> VertexOut {
var output : VertexOut;
output.pos = vec4<f32>();
output.col = 0.5;
return output;
}
fn non_entry_b() {
}
)";
auto* expect = R"(
struct tint_symbol {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
[[builtin(pointsize)]]
tint_pointsize : f32;
};
struct VertexOut {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
};
fn non_entry_a() {
}
[[stage(vertex)]]
fn entry() -> tint_symbol {
var output : VertexOut;
output.pos = vec4<f32>();
output.col = 0.5;
return tint_symbol(output.pos, output.col, 1.0);
}
fn non_entry_b() {
}
)";
auto got = Run<EmitVertexPointSize>(src);
EXPECT_EQ(expect, str(got));
}
// Make sure we capture the function return value in a temporary instead of
// re-evaluating it multiple times.
TEST_F(EmitVertexPointSizeTest, VertexStage_ReturnStructFromFunctionCall) {
auto* src = R"(
struct VertexOut {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
};
fn foo() -> VertexOut {
var output : VertexOut;
output.pos = vec4<f32>();
output.col = 0.5;
return output;
}
[[stage(vertex)]]
fn entry() -> VertexOut {
return foo();
}
)";
auto* expect = R"(
struct tint_symbol {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
[[builtin(pointsize)]]
tint_pointsize : f32;
};
struct VertexOut {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
};
fn foo() -> VertexOut {
var output : VertexOut;
output.pos = vec4<f32>();
output.col = 0.5;
return output;
}
[[stage(vertex)]]
fn entry() -> tint_symbol {
let tint_symbol_1 : VertexOut = foo();
return tint_symbol(tint_symbol_1.pos, tint_symbol_1.col, 1.0);
}
)";
auto got = Run<EmitVertexPointSize>(src);
EXPECT_EQ(expect, str(got));
}
TEST_F(EmitVertexPointSizeTest, VertexStage_MultipleReturnStatements) {
auto* src = R"(
[[stage(vertex)]]
fn entry([[location(0)]] toggle : u32) -> [[builtin(position)]] vec4<f32> {
if (toggle == 1u) {
return vec4<f32>(0.5, 0.5, 0.5, 0.5);
}
return vec4<f32>(1.0, 1.0, 1.0, 1.0);
}
)";
auto* expect = R"(
struct tint_symbol {
[[builtin(position)]]
position : vec4<f32>;
[[builtin(pointsize)]]
tint_pointsize : f32;
};
[[stage(vertex)]]
fn entry([[location(0)]] toggle : u32) -> tint_symbol {
if ((toggle == 1u)) {
return tint_symbol(vec4<f32>(0.5, 0.5, 0.5, 0.5), 1.0);
}
return tint_symbol(vec4<f32>(1.0, 1.0, 1.0, 1.0), 1.0);
}
)";
auto got = Run<EmitVertexPointSize>(src);
EXPECT_EQ(expect, str(got));
}
// Test that we re-use generated structures when we've seen the original return
// type before.
TEST_F(EmitVertexPointSizeTest, VertexStage_MultipleShaders) {
auto* src = R"(
struct VertexOut {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
};
[[stage(vertex)]]
fn entry1() -> [[builtin(position)]] vec4<f32> {
return vec4<f32>();
}
[[stage(vertex)]]
fn entry2() -> [[builtin(position)]] vec4<f32> {
return vec4<f32>(1.0, 1.0, 1.0, 1.0);
}
[[stage(vertex)]]
fn entry3() -> VertexOut {
var output : VertexOut;
output.pos = vec4<f32>();
output.col = 0.5;
return output;
}
[[stage(vertex)]]
fn entry4() -> VertexOut {
var output : VertexOut;
output.pos = vec4<f32>();
output.col = 0.75;
return output;
}
)";
auto* expect = R"(
struct tint_symbol {
[[builtin(position)]]
position : vec4<f32>;
[[builtin(pointsize)]]
tint_pointsize : f32;
};
struct tint_symbol_1 {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
[[builtin(pointsize)]]
tint_pointsize_1 : f32;
};
struct VertexOut {
[[builtin(position)]]
pos : vec4<f32>;
[[location(0)]]
col : f32;
};
[[stage(vertex)]]
fn entry1() -> tint_symbol {
return tint_symbol(vec4<f32>(), 1.0);
}
[[stage(vertex)]]
fn entry2() -> tint_symbol {
return tint_symbol(vec4<f32>(1.0, 1.0, 1.0, 1.0), 1.0);
}
[[stage(vertex)]]
fn entry3() -> tint_symbol_1 {
var output : VertexOut;
output.pos = vec4<f32>();
output.col = 0.5;
return tint_symbol_1(output.pos, output.col, 1.0);
}
[[stage(vertex)]]
fn entry4() -> tint_symbol_1 {
var output : VertexOut;
output.pos = vec4<f32>();
output.col = 0.75;
return tint_symbol_1(output.pos, output.col, 1.0);
}
)";
auto got = Run<EmitVertexPointSize>(src);
EXPECT_EQ(expect, str(got));
}
TEST_F(EmitVertexPointSizeTest, NonVertexStage) {
auto* src = R"(
[[stage(fragment)]]
@ -87,21 +338,34 @@ fn compute_entry() {
TEST_F(EmitVertexPointSizeTest, AttemptSymbolCollision) {
auto* src = R"(
struct VertexOut {
[[builtin(position)]]
tint_pointsize : vec4<f32>;
};
[[stage(vertex)]]
fn entry() -> [[builtin(position)]] vec4<f32> {
var tint_pointsize : f32;
return vec4<f32>();
fn entry() -> VertexOut {
return VertexOut(vec4<f32>());
}
)";
auto* expect = R"(
[[builtin(pointsize)]] var<out> tint_pointsize_1 : f32;
struct tint_symbol {
[[builtin(position)]]
tint_pointsize : vec4<f32>;
[[builtin(pointsize)]]
tint_pointsize_1 : f32;
};
struct VertexOut {
[[builtin(position)]]
tint_pointsize : vec4<f32>;
};
[[stage(vertex)]]
fn entry() -> [[builtin(position)]] vec4<f32> {
tint_pointsize_1 = 1.0;
var tint_pointsize : f32;
return vec4<f32>();
fn entry() -> tint_symbol {
let tint_symbol_1 : VertexOut = VertexOut(vec4<f32>());
return tint_symbol(tint_symbol_1.tint_pointsize, 1.0);
}
)";