From 3a465ba4a8fa7e046ea43a5476c33016b4cec258 Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Sun, 7 Aug 2016 19:59:35 +0100
Subject: [PATCH] VFP: Implement VLDR

---
 src/frontend/decoder/vfp2.h                   |  2 +-
 .../disassembler/disassembler_arm.cpp         |  5 +++++
 .../translate/translate_arm/translate_arm.h   |  3 +++
 src/frontend/translate/translate_arm/vfp2.cpp | 19 +++++++++++++++++++
 tests/arm/fuzz_arm.cpp                        | 12 ++++++++++++
 5 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/src/frontend/decoder/vfp2.h b/src/frontend/decoder/vfp2.h
index 244ec47d..f3b656a8 100644
--- a/src/frontend/decoder/vfp2.h
+++ b/src/frontend/decoder/vfp2.h
@@ -99,7 +99,7 @@ boost::optional<const VFP2Matcher<V>&> DecodeVFP2(u32 instruction) {
     // VSTM
     // VSTMDB
     // VPUSH
-    // VLDR
+    INST(&V::vfp2_VLDR,           "VLDR",                    "cccc1101UD01nnnndddd101zvvvvvvvv"),
     // VLDM
     // VLDMDB
     // VPOP
diff --git a/src/frontend/disassembler/disassembler_arm.cpp b/src/frontend/disassembler/disassembler_arm.cpp
index 776cd4fb..e5214ec9 100644
--- a/src/frontend/disassembler/disassembler_arm.cpp
+++ b/src/frontend/disassembler/disassembler_arm.cpp
@@ -653,6 +653,11 @@ public:
     std::string vfp2_VSQRT(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm) {
         return Common::StringFromFormat("vsqrt%s.%s %s, %s", CondToString(cond), sz ? "f64" : "f32", FPRegStr(sz, Vd, D).c_str(), FPRegStr(sz, Vm, M).c_str());
     }
+
+    std::string vfp2_VLDR(Cond cond, bool U, bool D, Reg n, size_t Vd, bool sz, Imm8 imm8) {
+        u32 imm32 = imm8 << 2;
+        return Common::StringFromFormat("vldr%s %s, [%s, #%c%u]", CondToString(cond), FPRegStr(sz, Vd, D).c_str(), RegToString(n), U ? '+' : '-', imm32);
+    }
 };
 
 std::string DisassembleArm(u32 instruction) {
diff --git a/src/frontend/translate/translate_arm/translate_arm.h b/src/frontend/translate/translate_arm/translate_arm.h
index 582c9c47..5ed79b37 100644
--- a/src/frontend/translate/translate_arm/translate_arm.h
+++ b/src/frontend/translate/translate_arm/translate_arm.h
@@ -344,6 +344,9 @@ struct ArmTranslatorVisitor final {
     bool vfp2_VABS(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm);
     bool vfp2_VNEG(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm);
     bool vfp2_VSQRT(Cond cond, bool D, size_t Vd, bool sz, bool M, size_t Vm);
+
+    // Floating-point load-store instructions
+    bool vfp2_VLDR(Cond cond, bool U, bool D, Reg n, size_t Vd, bool sz, Imm8 imm8);
 };
 
 } // namespace Arm
diff --git a/src/frontend/translate/translate_arm/vfp2.cpp b/src/frontend/translate/translate_arm/vfp2.cpp
index 8cb42c9d..7f931c35 100644
--- a/src/frontend/translate/translate_arm/vfp2.cpp
+++ b/src/frontend/translate/translate_arm/vfp2.cpp
@@ -360,5 +360,24 @@ bool ArmTranslatorVisitor::vfp2_VSQRT(Cond cond, bool D, size_t Vd, bool sz, boo
     return true;
 }
 
+bool ArmTranslatorVisitor::vfp2_VLDR(Cond cond, bool U, bool D, Reg n, size_t Vd, bool sz, Imm8 imm8) {
+    u32 imm32 = imm8 << 2;
+    ExtReg d = ToExtReg(sz, Vd, D);
+    // VLDR <{S,D}d>, [<Rn>, #+/-<imm32>]
+    if (ConditionPassed(cond)) {
+        auto base = n == Reg::PC ? ir.Imm32(ir.AlignPC(4)) : ir.GetRegister(n);
+        auto address = U ? ir.Add(base, ir.Imm32(imm32)) : ir.Sub(base, ir.Imm32(imm32));
+        if (sz) {
+            auto lo = ir.ReadMemory32(address);
+            auto hi = ir.ReadMemory32(ir.Add(address, ir.Imm32(4)));
+            if (ir.current_location.EFlag()) std::swap(lo, hi);
+            ir.SetExtendedRegister(d, ir.TransferToFP64(ir.Pack2x32To1x64(lo, hi)));
+        } else {
+            ir.SetExtendedRegister(d, ir.TransferToFP32(ir.ReadMemory32(address)));
+        }
+    }
+    return true;
+}
+
 } // namespace Arm
 } // namespace Dynarmic
diff --git a/tests/arm/fuzz_arm.cpp b/tests/arm/fuzz_arm.cpp
index efbb55fd..4d80f430 100644
--- a/tests/arm/fuzz_arm.cpp
+++ b/tests/arm/fuzz_arm.cpp
@@ -419,6 +419,18 @@ TEST_CASE("VFP: VMOV", "[JitX64][vfp]") {
     });
 }
 
+
+TEST_CASE("VFP: VMOV (reg), VLDR", "[JitX64][vfp]") {
+    const std::array<InstructionGenerator, 2> instructions = {{
+        InstructionGenerator("cccc11101D110000dddd101z01M0mmmm"),
+        InstructionGenerator("cccc1101UD01nnnndddd101zvvvvvvvv"),
+    }};
+
+    FuzzJitArm(1, 1, 10000, [&instructions]() -> u32 {
+        return instructions[RandInt<size_t>(0, instructions.size() - 1)].Generate();
+    });
+}
+
 TEST_CASE("Fuzz ARM data processing instructions", "[JitX64]") {
     const std::array<InstructionGenerator, 16> imm_instructions = {
             {