From 68bd9547c5870aa06cb04227675835159cea01f9 Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Sun, 7 Feb 2021 20:31:48 +0000
Subject: [PATCH] fuzz_arm: Correctly print thumb instruction listing

---
 src/common/llvm_disassemble.cpp | 30 ++++++++++++++++++++++++------
 src/common/llvm_disassemble.h   |  2 +-
 tests/A32/fuzz_arm.cpp          |  7 ++-----
 tests/print_info.cpp            |  2 +-
 4 files changed, 28 insertions(+), 13 deletions(-)

diff --git a/src/common/llvm_disassemble.cpp b/src/common/llvm_disassemble.cpp
index 88e79937..d3483107 100644
--- a/src/common/llvm_disassemble.cpp
+++ b/src/common/llvm_disassemble.cpp
@@ -54,20 +54,38 @@ std::string DisassembleX64(const void* begin, const void* end) {
     return result;
 }
 
-std::string DisassembleAArch32([[maybe_unused]] u32 instruction, [[maybe_unused]] u64 pc) {
+std::string DisassembleAArch32([[maybe_unused]] bool is_thumb, [[maybe_unused]] u32 pc, [[maybe_unused]] const u8* instructions, [[maybe_unused]] size_t length) {
     std::string result;
 
 #ifdef DYNARMIC_USE_LLVM
     LLVMInitializeARMTargetInfo();
     LLVMInitializeARMTargetMC();
     LLVMInitializeARMDisassembler();
-    LLVMDisasmContextRef llvm_ctx = LLVMCreateDisasm("armv8-arm", nullptr, 0, nullptr, nullptr);
+    LLVMDisasmContextRef llvm_ctx = LLVMCreateDisasm(is_thumb ? "thumbv8-arm" : "armv8-arm", nullptr, 0, nullptr, nullptr);
     LLVMSetDisasmOptions(llvm_ctx, LLVMDisassembler_Option_AsmPrinterVariant);
 
-    char buffer[80];
-    size_t inst_size = LLVMDisasmInstruction(llvm_ctx, (u8*)&instruction, sizeof(instruction), pc, buffer, sizeof(buffer));
-    result = inst_size > 0 ? buffer : "<invalid instruction>";
-    result += '\n';
+    char buffer[1024];
+    while (length) {
+        size_t inst_size = LLVMDisasmInstruction(llvm_ctx, const_cast<u8*>(instructions), length, pc, buffer, sizeof(buffer));
+
+        result += fmt::format("{:08x}    ", pc);
+        for (size_t i = 0; i < 4; i++) {
+            if (i < inst_size) {
+                result += fmt::format("{:02x}", instructions[inst_size - i - 1]);
+            } else {
+                result += "  ";
+            }
+        }
+        result += inst_size > 0 ? buffer : "<invalid instruction>";
+        result += '\n';
+
+        if (inst_size == 0) inst_size = is_thumb ? 2 : 4;
+        if (length <= inst_size) break;
+
+        pc += inst_size;
+        instructions += inst_size;
+        length -= inst_size;
+    }
 
     LLVMDisasmDispose(llvm_ctx);
 #else
diff --git a/src/common/llvm_disassemble.h b/src/common/llvm_disassemble.h
index a49ca2fd..0d9ac6a9 100644
--- a/src/common/llvm_disassemble.h
+++ b/src/common/llvm_disassemble.h
@@ -12,7 +12,7 @@
 namespace Dynarmic::Common {
 
 std::string DisassembleX64(const void* pos, const void* end);
-std::string DisassembleAArch32(u32 instruction, u64 pc = 0);
+std::string DisassembleAArch32(bool is_thumb, u32 pc, const u8* instructions, size_t length);
 std::string DisassembleAArch64(u32 instruction, u64 pc = 0);
 
 } // namespace Dynarmic::Common
diff --git a/tests/A32/fuzz_arm.cpp b/tests/A32/fuzz_arm.cpp
index 41b37733..2c69f754 100644
--- a/tests/A32/fuzz_arm.cpp
+++ b/tests/A32/fuzz_arm.cpp
@@ -16,8 +16,8 @@
 #include "common/common_types.h"
 #include "common/fp/fpcr.h"
 #include "common/fp/fpsr.h"
+#include "common/llvm_disassemble.h"
 #include "common/scope_exit.h"
-#include "frontend/A32/disassembler/disassembler.h"
 #include "frontend/A32/location_descriptor.h"
 #include "frontend/A32/translate/translate.h"
 #include "frontend/A32/types.h"
@@ -247,10 +247,7 @@ static void RunTestInstance(Dynarmic::A32::Jit& jit,
 
     SCOPE_FAIL {
         fmt::print("Instruction Listing:\n");
-        for (u32 instruction : instructions) {
-            fmt::print("{:08x} {}\n", instruction, A32::DisassembleArm(instruction));
-        }
-        fmt::print("\n");
+        fmt::print("{}\n", Common::DisassembleAArch32(std::is_same_v<TestEnv, ThumbTestEnv>, initial_pc, (const u8*)instructions.data(), instructions.size() * sizeof(instructions[0])));
 
         fmt::print("Initial register listing:\n");
         for (size_t i = 0; i < regs.size(); ++i) {
diff --git a/tests/print_info.cpp b/tests/print_info.cpp
index ccb1f1d6..48cbf587 100644
--- a/tests/print_info.cpp
+++ b/tests/print_info.cpp
@@ -54,7 +54,7 @@ const char* GetNameOfA64Instruction(u32 instruction) {
 }
 
 void PrintA32Instruction(u32 instruction) {
-    fmt::print("{:08x} {}\n", instruction, Common::DisassembleAArch32(instruction));
+    fmt::print("{:08x} {}\n", instruction, Common::DisassembleAArch32(false, 0, (u8*)&instruction, sizeof(instruction)));
     fmt::print("Name: {}\n", GetNameOfA32Instruction(instruction));
 
     const A32::LocationDescriptor location{0, {}, {}};