From 735e6c58be214233a7f149b25c68f5743bb7d419 Mon Sep 17 00:00:00 2001
From: Annomatg <47226753+Annomatg@users.noreply.github.com>
Date: Sun, 3 Feb 2019 21:21:14 +0100
Subject: [PATCH] Reduce Inst::NumArgs calls / opcodes: Prefer std::vector to
 std::map (#425)

* Don't call Inst::NumArgs in a loop conditional
* opcodes: Prefer a simple std::vector instead of a std::map
---
 src/backend/x64/reg_alloc.cpp    |  3 ++-
 src/frontend/ir/opcodes.cpp      | 20 ++++++++++----------
 src/ir_opt/verification_pass.cpp |  6 ++++--
 3 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/src/backend/x64/reg_alloc.cpp b/src/backend/x64/reg_alloc.cpp
index 30b3dd6c..c9bdc53d 100644
--- a/src/backend/x64/reg_alloc.cpp
+++ b/src/backend/x64/reg_alloc.cpp
@@ -229,7 +229,8 @@ bool Argument::IsInMemory() const {
 
 RegAlloc::ArgumentInfo RegAlloc::GetArgumentInfo(IR::Inst* inst) {
     ArgumentInfo ret = {Argument{*this}, Argument{*this}, Argument{*this}, Argument{*this}};
-    for (size_t i = 0; i < inst->NumArgs(); i++) {
+    const size_t num_args = inst->NumArgs();
+    for (size_t i = 0; i < num_args; i++) {
         const IR::Value& arg = inst->GetArg(i);
         ret[i].value = arg;
         if (!arg.IsImmediate() && !IsValuelessType(arg.GetType())) {
diff --git a/src/frontend/ir/opcodes.cpp b/src/frontend/ir/opcodes.cpp
index af038bac..b4c77ecc 100644
--- a/src/frontend/ir/opcodes.cpp
+++ b/src/frontend/ir/opcodes.cpp
@@ -45,34 +45,34 @@ constexpr Type NZCV = Type::NZCVFlags;
 constexpr Type Cond = Type::Cond;
 constexpr Type Table = Type::Table;
 
-static const std::map<Opcode, Meta> opcode_info {{
-#define OPCODE(name, type, ...) { Opcode::name, { #name, type, { __VA_ARGS__ } } },
-#define A32OPC(name, type, ...) { Opcode::A32##name, { #name, type, { __VA_ARGS__ } } },
-#define A64OPC(name, type, ...) { Opcode::A64##name, { #name, type, { __VA_ARGS__ } } },
+static const std::vector<Meta> opcode_info {
+#define OPCODE(name, type, ...) { #name, type, { __VA_ARGS__ } },
+#define A32OPC(name, type, ...) { #name, type, { __VA_ARGS__ } },
+#define A64OPC(name, type, ...) { #name, type, { __VA_ARGS__ } },
 #include "opcodes.inc"
 #undef OPCODE
 #undef A32OPC
 #undef A64OPC
-}};
+};
 
 } // namespace OpcodeInfo
 
 Type GetTypeOf(Opcode op) {
-    return OpcodeInfo::opcode_info.at(op).type;
+    return OpcodeInfo::opcode_info.at(static_cast<size_t>(op)).type;
 }
 
 size_t GetNumArgsOf(Opcode op) {
-    return OpcodeInfo::opcode_info.at(op).arg_types.size();
+    return OpcodeInfo::opcode_info.at(static_cast<size_t>(op)).arg_types.size();
 }
 
 Type GetArgTypeOf(Opcode op, size_t arg_index) {
-    return OpcodeInfo::opcode_info.at(op).arg_types.at(arg_index);
+    return OpcodeInfo::opcode_info.at(static_cast<size_t>(op)).arg_types.at(arg_index);
 }
 
 std::string GetNameOf(Opcode op) {
-    if (OpcodeInfo::opcode_info.count(op) == 0)
+    if (OpcodeInfo::opcode_info.size() <= static_cast<size_t>(op))
         return fmt::format("Unknown Opcode {}", static_cast<Opcode>(op));
-    return OpcodeInfo::opcode_info.at(op).name;
+    return OpcodeInfo::opcode_info.at(static_cast<size_t>(op)).name;
 }
 
 std::ostream& operator<<(std::ostream& o, Opcode opcode) {
diff --git a/src/ir_opt/verification_pass.cpp b/src/ir_opt/verification_pass.cpp
index ef590b45..d81df787 100644
--- a/src/ir_opt/verification_pass.cpp
+++ b/src/ir_opt/verification_pass.cpp
@@ -18,7 +18,8 @@ namespace Dynarmic::Optimization {
 
 void VerificationPass(const IR::Block& block) {
     for (const auto& inst : block) {
-        for (size_t i = 0; i < inst.NumArgs(); i++) {
+        const size_t num_args = inst.NumArgs();
+        for (size_t i = 0; i < num_args; i++) {
             IR::Type t1 = inst.GetArg(i).GetType();
             IR::Type t2 = IR::GetArgTypeOf(inst.GetOpcode(), i);
             if (!IR::AreTypesCompatible(t1, t2)) {
@@ -30,7 +31,8 @@ void VerificationPass(const IR::Block& block) {
 
     std::map<IR::Inst*, size_t> actual_uses;
     for (const auto& inst : block) {
-        for (size_t i = 0; i < inst.NumArgs(); i++) {
+        const size_t num_args = inst.NumArgs();
+        for (size_t i = 0; i < num_args; i++) {
             if (!inst.GetArg(i).IsImmediate()) {
                 actual_uses[inst.GetArg(i).GetInst()]++;
             }