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-rw-r--r--src/core/arm/interpreter/armsupp.cpp123
1 files changed, 121 insertions, 2 deletions
diff --git a/src/core/arm/interpreter/armsupp.cpp b/src/core/arm/interpreter/armsupp.cpp
index 30519f216..8b3661c8f 100644
--- a/src/core/arm/interpreter/armsupp.cpp
+++ b/src/core/arm/interpreter/armsupp.cpp
@@ -227,8 +227,9 @@ ARMul_CPSRAltered (ARMul_State * state)
//state->Cpsr &= ~CBIT;
ASSIGNV ((state->Cpsr & VBIT) != 0);
//state->Cpsr &= ~VBIT;
- ASSIGNS ((state->Cpsr & SBIT) != 0);
- //state->Cpsr &= ~SBIT;
+ ASSIGNQ ((state->Cpsr & QBIT) != 0);
+ //state->Cpsr &= ~QBIT;
+ state->GEFlag = (state->Cpsr & 0x000F0000);
#ifdef MODET
ASSIGNT ((state->Cpsr & TBIT) != 0);
//state->Cpsr &= ~TBIT;
@@ -391,6 +392,15 @@ ARMul_NthReg (ARMword instr, unsigned number)
return (bit - 1);
}
+/* Unsigned sum of absolute difference */
+u8 ARMul_UnsignedAbsoluteDifference(u8 left, u8 right)
+{
+ if (left > right)
+ return left - right;
+
+ return right - left;
+}
+
/* Assigns the N and Z flags depending on the value of result. */
void
@@ -443,6 +453,14 @@ ARMul_AddOverflow (ARMul_State * state, ARMword a, ARMword b, ARMword result)
ASSIGNV (AddOverflow (a, b, result));
}
+/* Assigns the Q flag if the given result is considered an overflow from the addition of a and b */
+void ARMul_AddOverflowQ(ARMul_State* state, ARMword a, ARMword b)
+{
+ u32 result = a + b;
+ if (((result ^ a) & (u32)0x80000000) && ((a ^ b) & (u32)0x80000000) == 0)
+ SETQ;
+}
+
/* Assigns the C flag after an subtraction of a and b to give result. */
void
@@ -460,6 +478,107 @@ ARMul_SubOverflow (ARMul_State * state, ARMword a, ARMword b, ARMword result)
ASSIGNV (SubOverflow (a, b, result));
}
+/* 8-bit signed saturated addition */
+u8 ARMul_SignedSaturatedAdd8(u8 left, u8 right)
+{
+ u8 result = left + right;
+
+ if (((result ^ left) & 0x80) && ((left ^ right) & 0x80) == 0) {
+ if (left & 0x80)
+ result = 0x80;
+ else
+ result = 0x7F;
+ }
+
+ return result;
+}
+
+/* 8-bit signed saturated subtraction */
+u8 ARMul_SignedSaturatedSub8(u8 left, u8 right)
+{
+ u8 result = left - right;
+
+ if (((result ^ left) & 0x80) && ((left ^ right) & 0x80) != 0) {
+ if (left & 0x80)
+ result = 0x80;
+ else
+ result = 0x7F;
+ }
+
+ return result;
+}
+
+/* 16-bit signed saturated addition */
+u16 ARMul_SignedSaturatedAdd16(u16 left, u16 right)
+{
+ u16 result = left + right;
+
+ if (((result ^ left) & 0x8000) && ((left ^ right) & 0x8000) == 0) {
+ if (left & 0x8000)
+ result = 0x8000;
+ else
+ result = 0x7FFF;
+ }
+
+ return result;
+}
+
+/* 16-bit signed saturated subtraction */
+u16 ARMul_SignedSaturatedSub16(u16 left, u16 right)
+{
+ u16 result = left - right;
+
+ if (((result ^ left) & 0x8000) && ((left ^ right) & 0x8000) != 0) {
+ if (left & 0x8000)
+ result = 0x8000;
+ else
+ result = 0x7FFF;
+ }
+
+ return result;
+}
+
+/* 8-bit unsigned saturated addition */
+u8 ARMul_UnsignedSaturatedAdd8(u8 left, u8 right)
+{
+ u8 result = left + right;
+
+ if (result < left)
+ result = 0xFF;
+
+ return result;
+}
+
+/* 16-bit unsigned saturated addition */
+u16 ARMul_UnsignedSaturatedAdd16(u16 left, u16 right)
+{
+ u16 result = left + right;
+
+ if (result < left)
+ result = 0xFFFF;
+
+ return result;
+}
+
+/* 8-bit unsigned saturated subtraction */
+u8 ARMul_UnsignedSaturatedSub8(u8 left, u8 right)
+{
+ if (left <= right)
+ return 0;
+
+ return left - right;
+}
+
+/* 16-bit unsigned saturated subtraction */
+u16 ARMul_UnsignedSaturatedSub16(u16 left, u16 right)
+{
+ if (left <= right)
+ return 0;
+
+ return left - right;
+}
+
+
/* This function does the work of generating the addresses used in an
LDC instruction. The code here is always post-indexed, it's up to the
caller to get the input address correct and to handle base register