dyncom: Handle left-operand PC correctly for data-processing ops

This is considered deprecated in the ARM manual (using PC as an operand),
however, this is still able to be executed on the MPCore (which I'm quite
sure would be rare to begin with).

src/core/arm/dyncom/arm_dyncom_interpreter.cpp

@@ -3924,9 +3924,13 @@ unsigned InterpreterMainLoop(ARMul_State* cpu) {
         if (inst_base->cond == 0xE || CondPassed(cpu, inst_base->cond)) {
             adc_inst* const inst_cream = (adc_inst*)inst_base->component;
 
+            u32 rn_val = RN;
+            if (inst_cream->Rn == 15)
+                rn_val += 2 * cpu->GetInstructionSize();
+
             bool carry;
             bool overflow;
-            RD = AddWithCarry(RN, SHIFTER_OPERAND, cpu->CFlag, &carry, &overflow);
+            RD = AddWithCarry(rn_val, SHIFTER_OPERAND, cpu->CFlag, &carry, &overflow);
 
             if (inst_cream->S && (inst_cream->Rd == 15)) {
                 if (CurrentModeHasSPSR) {
@@ -3987,11 +3991,17 @@ unsigned InterpreterMainLoop(ARMul_State* cpu) {
     }
     AND_INST:
     {
-        and_inst *inst_cream = (and_inst *)inst_base->component;
-        if ((inst_base->cond == 0xe) || CondPassed(cpu, inst_base->cond)) {
+        if (inst_base->cond == 0xE || CondPassed(cpu, inst_base->cond)) {
+            and_inst* const inst_cream = (and_inst*)inst_base->component;
+
             u32 lop = RN;
             u32 rop = SHIFTER_OPERAND;
+
+            if (inst_cream->Rn == 15)
+                lop += 2 * cpu->GetInstructionSize();
+
             RD = lop & rop;
+
             if (inst_cream->S && (inst_cream->Rd == 15)) {
                 if (CurrentModeHasSPSR) {
                     cpu->Cpsr = cpu->Spsr_copy;
@@ -4164,9 +4174,13 @@ unsigned InterpreterMainLoop(ARMul_State* cpu) {
         if (inst_base->cond == 0xE || CondPassed(cpu, inst_base->cond)) {
             cmn_inst* const inst_cream = (cmn_inst*)inst_base->component;
 
+            u32 rn_val = RN;
+            if (inst_cream->Rn == 15)
+                rn_val += 2 * cpu->GetInstructionSize();
+
             bool carry;
             bool overflow;
-            u32 result = AddWithCarry(RN, SHIFTER_OPERAND, 0, &carry, &overflow);
+            u32 result = AddWithCarry(rn_val, SHIFTER_OPERAND, 0, &carry, &overflow);
 
             UPDATE_NFLAG(result);
             UPDATE_ZFLAG(result);
@@ -4905,6 +4919,10 @@ unsigned InterpreterMainLoop(ARMul_State* cpu) {
 
             u32 lop = RN;
             u32 rop = SHIFTER_OPERAND;
+
+            if (inst_cream->Rn == 15)
+                lop += 2 * cpu->GetInstructionSize();
+
             RD = lop | rop;
 
             if (inst_cream->S && (inst_cream->Rd == 15)) {
@@ -5195,9 +5213,13 @@ unsigned InterpreterMainLoop(ARMul_State* cpu) {
         if (inst_base->cond == 0xE || CondPassed(cpu, inst_base->cond)) {
             rsc_inst* const inst_cream = (rsc_inst*)inst_base->component;
 
+            u32 rn_val = RN;
+            if (inst_cream->Rn == 15)
+                rn_val += 2 * cpu->GetInstructionSize();
+
             bool carry;
             bool overflow;
-            RD = AddWithCarry(~RN, SHIFTER_OPERAND, cpu->CFlag, &carry, &overflow);
+            RD = AddWithCarry(~rn_val, SHIFTER_OPERAND, cpu->CFlag, &carry, &overflow);
 
             if (inst_cream->S && (inst_cream->Rd == 15)) {
                 if (CurrentModeHasSPSR) {
@@ -5335,9 +5357,13 @@ unsigned InterpreterMainLoop(ARMul_State* cpu) {
         if (inst_base->cond == 0xE || CondPassed(cpu, inst_base->cond)) {
             sbc_inst* const inst_cream = (sbc_inst*)inst_base->component;
 
+            u32 rn_val = RN;
+            if (inst_cream->Rn == 15)
+                rn_val += 2 * cpu->GetInstructionSize();
+
             bool carry;
             bool overflow;
-            RD = AddWithCarry(RN, ~SHIFTER_OPERAND, cpu->CFlag, &carry, &overflow);
+            RD = AddWithCarry(rn_val, ~SHIFTER_OPERAND, cpu->CFlag, &carry, &overflow);
 
             if (inst_cream->S && (inst_cream->Rd == 15)) {
                 if (CurrentModeHasSPSR) {
@@ -6171,7 +6197,7 @@ unsigned InterpreterMainLoop(ARMul_State* cpu) {
 
             u32 rn_val = RN;
             if (inst_cream->Rn == 15)
-                rn_val += 8;
+                rn_val += 2 * cpu->GetInstructionSize();
 
             bool carry;
             bool overflow;