ARMeilleure: Thumb support (All T16 instructions) (#3105)

* Decoders: Add InITBlock argument

* OpCodeTable: Minor cleanup

* OpCodeTable: Remove existing thumb instruction implementations

* OpCodeTable: Prepare for thumb instructions

* OpCodeTables: Improve thumb fast lookup

* Tests: Prepare for thumb tests

* T16: Implement BX

* T16: Implement LSL/LSR/ASR (imm)

* T16: Implement ADDS, SUBS (reg)

* T16: Implement ADDS, SUBS (3-bit immediate)

* T16: Implement MOVS, CMP, ADDS, SUBS (8-bit immediate)

* T16: Implement ANDS, EORS, LSLS, LSRS, ASRS, ADCS, SBCS, RORS, TST, NEGS, CMP, CMN, ORRS, MULS, BICS, MVNS (low registers)

* T16: Implement ADD, CMP, MOV (high reg)

* T16: Implement BLX (reg)

* T16: Implement LDR (literal)

* T16: Implement {LDR,STR}{,H,B,SB,SH} (register)

* T16: Implement {LDR,STR}{,B,H} (immediate)

* T16: Implement LDR/STR (SP)

* T16: Implement ADR

* T16: Implement Add to SP (immediate)

* T16: Implement ADD/SUB (SP)

* T16: Implement SXTH, SXTB, UXTH, UTXB

* T16: Implement CBZ, CBNZ

* T16: Implement PUSH, POP

* T16: Implement REV, REV16, REVSH

* T16: Implement NOP

* T16: Implement LDM, STM

* T16: Implement SVC

* T16: Implement B (conditional)

* T16: Implement B (unconditional)

* T16: Implement IT

* fixup! T16: Implement ADD/SUB (SP)

* fixup! T16: Implement Add to SP (immediate)

* fixup! T16: Implement IT

* CpuTestThumb: Add randomized tests

* Remove inITBlock argument

* Address nits

* Use index to handle IfThenBlockState

* Reduce line noise

* fixup

* nit

1 files changed, 40 insertions, 1 deletions

diff --git a/Ryujinx.Tests/Cpu/CpuTest32.cs b/Ryujinx.Tests/Cpu/CpuTest32.cs
index 5d24af39..7fa9ba09 100644
--- a/Ryujinx.Tests/Cpu/CpuTest32.cs
+++ b/Ryujinx.Tests/Cpu/CpuTest32.cs
@@ -106,6 +106,18 @@ namespace Ryujinx.Tests.Cpu
             _currAddress += 4;
         }
 
+        protected void ThumbOpcode(ushort opcode)
+        {
+            _memory.Write(_currAddress, opcode);
+
+            if (_unicornAvailable)
+            {
+                _unicornEmu.MemoryWrite16(_currAddress, opcode);
+            }
+
+            _currAddress += 2;
+        }
+
         protected ExecutionContext GetContext() => _context;
 
         protected void SetContext(uint r0 = 0,
@@ -126,7 +138,8 @@ namespace Ryujinx.Tests.Cpu
                                   bool carry = false,
                                   bool zero = false,
                                   bool negative = false,
-                                  int fpscr = 0)
+                                  int fpscr = 0,
+                                  bool thumb = false)
         {
             _context.SetX(0, r0);
             _context.SetX(1, r1);
@@ -151,6 +164,8 @@ namespace Ryujinx.Tests.Cpu
 
             SetFpscr((uint)fpscr);
 
+            _context.SetPstateFlag(PState.TFlag, thumb);
+
             if (_unicornAvailable)
             {
                 _unicornEmu.R[0] = r0;
@@ -175,6 +190,8 @@ namespace Ryujinx.Tests.Cpu
                 _unicornEmu.NegativeFlag = negative;
 
                 _unicornEmu.Fpscr = fpscr;
+
+                _unicornEmu.ThumbFlag = thumb;
             }
         }
 
@@ -218,6 +235,28 @@ namespace Ryujinx.Tests.Cpu
             return GetContext();
         }
 
+        protected ExecutionContext SingleThumbOpcode(ushort opcode,
+                                                     uint r0 = 0,
+                                                     uint r1 = 0,
+                                                     uint r2 = 0,
+                                                     uint r3 = 0,
+                                                     uint sp = 0,
+                                                     bool saturation = false,
+                                                     bool overflow = false,
+                                                     bool carry = false,
+                                                     bool zero = false,
+                                                     bool negative = false,
+                                                     int fpscr = 0,
+                                                     bool runUnicorn = true)
+        {
+            ThumbOpcode(opcode);
+            ThumbOpcode(0x4770); // BX LR
+            SetContext(r0, r1, r2, r3, sp, default, default, default, default, default, default, default, default, saturation, overflow, carry, zero, negative, fpscr, thumb: true);
+            ExecuteOpcodes(runUnicorn);
+
+            return GetContext();
+        }
+
         protected void SetWorkingMemory(uint offset, byte[] data)
         {
             _memory.Write(DataBaseAddress + offset, data);