From f7aaf92a04e36785befbba738a218fea20a49d62 Mon Sep 17 00:00:00 2001
From: Greg Fischer <greg@lunarg.com>
Date: Sun, 8 May 2022 15:10:07 -0600
Subject: [PATCH] Add structs to eliminate dead input components
Will eliminate all trailing members of input struct that are not
referenced.
---
.../eliminate_dead_input_components_pass.cpp | 81 ++++++++++++++-----
.../eliminate_dead_input_components_pass.h | 8 +-
.../eliminate_dead_input_components_test.cpp | 64 +++++++++++++++
3 files changed, 133 insertions(+), 20 deletions(-)
diff --git a/source/opt/eliminate_dead_input_components_pass.cpp b/source/opt/eliminate_dead_input_components_pass.cpp
index f383136d55..aa2776bbd3 100644
--- a/source/opt/eliminate_dead_input_components_pass.cpp
+++ b/source/opt/eliminate_dead_input_components_pass.cpp
@@ -56,21 +56,30 @@ Pass::Status EliminateDeadInputComponentsPass::Process() {
continue;
}
const analysis::Array* arr_type = ptr_type->pointee_type()->AsArray();
- if (arr_type == nullptr) {
+ if (arr_type != nullptr) {
+ unsigned arr_len_id = arr_type->LengthId();
+ Instruction* arr_len_inst = def_use_mgr->GetDef(arr_len_id);
+ if (arr_len_inst->opcode() != SpvOpConstant) {
+ continue;
+ }
+ // SPIR-V requires array size is >= 1, so this works for signed or
+ // unsigned size
+ unsigned original_max =
+ arr_len_inst->GetSingleWordInOperand(kConstantValueInIdx) - 1;
+ unsigned max_idx = FindMaxIndex(var, original_max);
+ if (max_idx != original_max) {
+ ChangeArrayLength(var, max_idx + 1);
+ modified = true;
+ }
continue;
}
- unsigned arr_len_id = arr_type->LengthId();
- Instruction* arr_len_inst = def_use_mgr->GetDef(arr_len_id);
- if (arr_len_inst->opcode() != SpvOpConstant) {
- continue;
- }
- // SPIR-V requires array size is >= 1, so this works for signed or
- // unsigned size
- unsigned original_max =
- arr_len_inst->GetSingleWordInOperand(kConstantValueInIdx) - 1;
+ const analysis::Struct* struct_type = ptr_type->pointee_type()->AsStruct();
+ if (struct_type == nullptr) continue;
+ const auto elt_types = struct_type->element_types();
+ unsigned original_max = static_cast<unsigned>(elt_types.size()) - 1;
unsigned max_idx = FindMaxIndex(var, original_max);
if (max_idx != original_max) {
- ChangeArrayLength(var, max_idx + 1);
+ ChangeStructLength(var, max_idx + 1);
modified = true;
}
}
@@ -116,12 +125,13 @@ unsigned EliminateDeadInputComponentsPass::FindMaxIndex(Instruction& var,
return seen_non_const_ac ? original_max : max;
}
-void EliminateDeadInputComponentsPass::ChangeArrayLength(Instruction& arr,
+void EliminateDeadInputComponentsPass::ChangeArrayLength(Instruction& arr_var,
unsigned length) {
analysis::TypeManager* type_mgr = context()->get_type_mgr();
analysis::ConstantManager* const_mgr = context()->get_constant_mgr();
analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr();
- analysis::Pointer* ptr_type = type_mgr->GetType(arr.type_id())->AsPointer();
+ analysis::Pointer* ptr_type =
+ type_mgr->GetType(arr_var.type_id())->AsPointer();
const analysis::Array* arr_ty = ptr_type->pointee_type()->AsArray();
assert(arr_ty && "expecting array type");
uint32_t length_id = const_mgr->GetUIntConst(length);
@@ -131,15 +141,48 @@ void EliminateDeadInputComponentsPass::ChangeArrayLength(Instruction& arr,
analysis::Pointer new_ptr_ty(reg_new_arr_ty, SpvStorageClassInput);
analysis::Type* reg_new_ptr_ty = type_mgr->GetRegisteredType(&new_ptr_ty);
uint32_t new_ptr_ty_id = type_mgr->GetTypeInstruction(reg_new_ptr_ty);
- arr.SetResultType(new_ptr_ty_id);
- def_use_mgr->AnalyzeInstUse(&arr);
- // Move array OpVariable instruction after its new type to preserve order
- USE_ASSERT(arr.GetSingleWordInOperand(kVariableStorageClassInIdx) !=
+ arr_var.SetResultType(new_ptr_ty_id);
+ def_use_mgr->AnalyzeInstUse(&arr_var);
+ // Move arr_var after its new type to preserve order
+ USE_ASSERT(arr_var.GetSingleWordInOperand(kVariableStorageClassInIdx) !=
+ SpvStorageClassFunction &&
+ "cannot move Function variable");
+ Instruction* new_ptr_ty_inst = def_use_mgr->GetDef(new_ptr_ty_id);
+ arr_var.RemoveFromList();
+ arr_var.InsertAfter(new_ptr_ty_inst);
+}
+
+void EliminateDeadInputComponentsPass::ChangeStructLength(
+ Instruction& struct_var, unsigned length) {
+ analysis::TypeManager* type_mgr = context()->get_type_mgr();
+ analysis::Pointer* ptr_type =
+ type_mgr->GetType(struct_var.type_id())->AsPointer();
+ const analysis::Struct* struct_ty = ptr_type->pointee_type()->AsStruct();
+ assert(struct_ty && "expecting struct type");
+ const auto orig_elt_types = struct_ty->element_types();
+ std::vector<const analysis::Type*> new_elt_types;
+ for (unsigned u = 0; u < length; ++u)
+ new_elt_types.push_back(orig_elt_types[u]);
+ analysis::Struct new_struct_ty(new_elt_types);
+ analysis::Type* reg_new_struct_ty =
+ type_mgr->GetRegisteredType(&new_struct_ty);
+ uint32_t new_struct_ty_id = type_mgr->GetTypeInstruction(reg_new_struct_ty);
+ uint32_t old_struct_ty_id = type_mgr->GetTypeInstruction(struct_ty);
+ analysis::DecorationManager* deco_mgr = context()->get_decoration_mgr();
+ deco_mgr->CloneDecorations(old_struct_ty_id, new_struct_ty_id);
+ analysis::Pointer new_ptr_ty(reg_new_struct_ty, SpvStorageClassInput);
+ analysis::Type* reg_new_ptr_ty = type_mgr->GetRegisteredType(&new_ptr_ty);
+ uint32_t new_ptr_ty_id = type_mgr->GetTypeInstruction(reg_new_ptr_ty);
+ struct_var.SetResultType(new_ptr_ty_id);
+ analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr();
+ def_use_mgr->AnalyzeInstUse(&struct_var);
+ // Move struct_var after its new type to preserve order
+ USE_ASSERT(struct_var.GetSingleWordInOperand(kVariableStorageClassInIdx) !=
SpvStorageClassFunction &&
"cannot move Function variable");
Instruction* new_ptr_ty_inst = def_use_mgr->GetDef(new_ptr_ty_id);
- arr.RemoveFromList();
- arr.InsertAfter(new_ptr_ty_inst);
+ struct_var.RemoveFromList();
+ struct_var.InsertAfter(new_ptr_ty_inst);
}
} // namespace opt
diff --git a/source/opt/eliminate_dead_input_components_pass.h b/source/opt/eliminate_dead_input_components_pass.h
index b77857f4e9..a3a133c2bb 100644
--- a/source/opt/eliminate_dead_input_components_pass.h
+++ b/source/opt/eliminate_dead_input_components_pass.h
@@ -30,7 +30,10 @@ class EliminateDeadInputComponentsPass : public Pass {
public:
explicit EliminateDeadInputComponentsPass() {}
- const char* name() const override { return "reduce-load-size"; }
+ const char* name() const override {
+ return "eliminate-dead-input-components";
+ }
+
Status Process() override;
// Return the mask of preserved Analyses.
@@ -51,6 +54,9 @@ class EliminateDeadInputComponentsPass : public Pass {
// Change the length of the array |inst| to |length|
void ChangeArrayLength(Instruction& inst, unsigned length);
+
+ // Change the length of the struct |struct_var| to |length|
+ void ChangeStructLength(Instruction& struct_var, unsigned length);
};
} // namespace opt
diff --git a/test/opt/eliminate_dead_input_components_test.cpp b/test/opt/eliminate_dead_input_components_test.cpp
index b0098f733a..822914a860 100644
--- a/test/opt/eliminate_dead_input_components_test.cpp
+++ b/test/opt/eliminate_dead_input_components_test.cpp
@@ -399,6 +399,70 @@ TEST_F(ElimDeadInputComponentsTest, NoElimNonIndexedAccessChain) {
SinglePassRunAndMatch<EliminateDeadInputComponentsPass>(text, true);
}
+TEST_F(ElimDeadInputComponentsTest, ElimStructMember) {
+ // Should eliminate uv
+ //
+ // #version 450
+ //
+ // in Vertex {
+ // vec4 Cd;
+ // vec2 uv;
+ // } iVert;
+ //
+ // out vec4 fragColor;
+ //
+ // void main()
+ // {
+ // vec4 color = vec4(iVert.Cd);
+ // fragColor = color;
+ // }
+ const std::string text = R"(
+ OpCapability Shader
+ %1 = OpExtInstImport "GLSL.std.450"
+ OpMemoryModel Logical GLSL450
+ OpEntryPoint Fragment %main "main" %iVert %fragColor
+ OpExecutionMode %main OriginUpperLeft
+ OpSource GLSL 450
+ OpName %main "main"
+ OpName %Vertex "Vertex"
+ OpMemberName %Vertex 0 "Cd"
+ OpMemberName %Vertex 1 "uv"
+ OpName %iVert "iVert"
+ OpName %fragColor "fragColor"
+ OpDecorate %Vertex Block
+ OpDecorate %iVert Location 0
+ OpDecorate %fragColor Location 0
+ %void = OpTypeVoid
+ %3 = OpTypeFunction %void
+ %float = OpTypeFloat 32
+ %v4float = OpTypeVector %float 4
+ %v2float = OpTypeVector %float 2
+ %Vertex = OpTypeStruct %v4float %v2float
+; CHECK: %Vertex = OpTypeStruct %v4float %v2float
+; CHECK: [[sty:%\w+]] = OpTypeStruct %v4float
+%_ptr_Input_Vertex = OpTypePointer Input %Vertex
+; CHECK: [[pty:%\w+]] = OpTypePointer Input [[sty]]
+ %iVert = OpVariable %_ptr_Input_Vertex Input
+; CHECK: %iVert = OpVariable [[pty]] Input
+ %int = OpTypeInt 32 1
+ %int_0 = OpConstant %int 0
+%_ptr_Input_v4float = OpTypePointer Input %v4float
+%_ptr_Output_v4float = OpTypePointer Output %v4float
+ %fragColor = OpVariable %_ptr_Output_v4float Output
+ %main = OpFunction %void None %3
+ %5 = OpLabel
+ %17 = OpAccessChain %_ptr_Input_v4float %iVert %int_0
+ %18 = OpLoad %v4float %17
+ OpStore %fragColor %18
+ OpReturn
+ OpFunctionEnd
+)";
+
+ SetTargetEnv(SPV_ENV_VULKAN_1_3);
+ SetAssembleOptions(SPV_TEXT_TO_BINARY_OPTION_PRESERVE_NUMERIC_IDS);
+ SinglePassRunAndMatch<EliminateDeadInputComponentsPass>(text, true);
+}
+
} // namespace
} // namespace opt
} // namespace spvtools