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dyncom: Implement USAT/SSAT

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This commit is contained in:
Lioncash 2014-12-29 18:47:20 -05:00
parent 2d2aa2c0be
commit 8fa16a8c50
3 changed files with 137 additions and 2 deletions
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100
src/core/arm/dyncom/arm_dyncom_interpreter.cpp
View file

@ -1275,6 +1275,14 @@ typedef struct _smla_inst {
unsigned int Rn;
} smla_inst;
typedef struct ssat_inst {
unsigned int Rn;
unsigned int Rd;
unsigned int imm5;
unsigned int sat_imm;
unsigned int shift_type;
} ssat_inst;
typedef struct umaal_inst {
unsigned int Rn;
unsigned int Rm;
@ -2742,7 +2750,24 @@ ARM_INST_PTR INTERPRETER_TRANSLATE(smulw)(unsigned int inst, int index)
}
ARM_INST_PTR INTERPRETER_TRANSLATE(smusd)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("SMUSD"); }
ARM_INST_PTR INTERPRETER_TRANSLATE(srs)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("SRS"); }
ARM_INST_PTR INTERPRETER_TRANSLATE(ssat)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("SSAT"); }
ARM_INST_PTR INTERPRETER_TRANSLATE(ssat)(unsigned int inst, int index)
{
arm_inst* const inst_base = (arm_inst*)AllocBuffer(sizeof(arm_inst) + sizeof(ssat_inst));
ssat_inst* const inst_cream = (ssat_inst*) inst_base->component;
inst_base->cond = BITS(inst, 28, 31);
inst_base->idx = index;
inst_base->br = NON_BRANCH;
inst_base->load_r15 = 0;
inst_cream->Rn = BITS(inst, 0, 3);
inst_cream->Rd = BITS(inst, 12, 15);
inst_cream->imm5 = BITS(inst, 7, 11);
inst_cream->sat_imm = BITS(inst, 16, 20);
inst_cream->shift_type = BIT(inst, 6);
return inst_base;
}
ARM_INST_PTR INTERPRETER_TRANSLATE(ssat16)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("SSAT16"); }
ARM_INST_PTR INTERPRETER_TRANSLATE(ssub8)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("SSUB8"); }
ARM_INST_PTR INTERPRETER_TRANSLATE(ssub16)(unsigned int inst, int index)
@ -3344,7 +3369,10 @@ ARM_INST_PTR INTERPRETER_TRANSLATE(usad8)(unsigned int inst, int index)
{
return INTERPRETER_TRANSLATE(usada8)(inst, index);
}
ARM_INST_PTR INTERPRETER_TRANSLATE(usat)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("USAT"); }
ARM_INST_PTR INTERPRETER_TRANSLATE(usat)(unsigned int inst, int index)
{
return INTERPRETER_TRANSLATE(ssat)(inst, index);
}
ARM_INST_PTR INTERPRETER_TRANSLATE(usat16)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("USAT16"); }
ARM_INST_PTR INTERPRETER_TRANSLATE(usub16)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("USUB16"); }
ARM_INST_PTR INTERPRETER_TRANSLATE(usub8)(unsigned int inst, int index) { UNIMPLEMENTED_INSTRUCTION("USUB8"); }
@ -6284,6 +6312,40 @@ unsigned InterpreterMainLoop(ARMul_State* state)
SMUSD_INST:
SRS_INST:
SSAT_INST:
{
INC_ICOUNTER;
if (inst_base->cond == 0xE || CondPassed(cpu, inst_base->cond)) {
ssat_inst* const inst_cream = (ssat_inst*)inst_base->component;
u8 shift_type = inst_cream->shift_type;
u8 shift_amount = inst_cream->imm5;
u32 rn_val = RN;
// 32-bit ASR is encoded as an amount of 0.
if (shift_type == 1 && shift_amount == 0)
shift_amount = 31;
if (shift_type == 0)
rn_val <<= shift_amount;
else if (shift_type == 1)
rn_val = ((s32)rn_val >> shift_amount);
bool saturated = false;
rn_val = ARMul_SignedSatQ(rn_val, inst_cream->sat_imm, &saturated);
if (saturated)
cpu->Cpsr |= (1 << 27);
RD = rn_val;
}
cpu->Reg[15] += GET_INST_SIZE(cpu);
INC_PC(sizeof(ssat_inst));
FETCH_INST;
GOTO_NEXT_INST;
}
SSAT16_INST:
SSUB8_INST:
STC_INST:
@ -7140,6 +7202,40 @@ unsigned InterpreterMainLoop(ARMul_State* state)
}
USAT_INST:
{
INC_ICOUNTER;
if (inst_base->cond == 0xE || CondPassed(cpu, inst_base->cond)) {
ssat_inst* const inst_cream = (ssat_inst*)inst_base->component;
u8 shift_type = inst_cream->shift_type;
u8 shift_amount = inst_cream->imm5;
u32 rn_val = RN;
// 32-bit ASR is encoded as an amount of 0.
if (shift_type == 1 && shift_amount == 0)
shift_amount = 31;
if (shift_type == 0)
rn_val <<= shift_amount;
else if (shift_type == 1)
rn_val = ((s32)rn_val >> shift_amount);
bool saturated = false;
rn_val = ARMul_UnsignedSatQ(rn_val, inst_cream->sat_imm, &saturated);
if (saturated)
cpu->Cpsr |= (1 << 27);
RD = rn_val;
}
cpu->Reg[15] += GET_INST_SIZE(cpu);
INC_PC(sizeof(ssat_inst));
FETCH_INST;
GOTO_NEXT_INST;
}
USAT16_INST:
USUB16_INST:
USUB8_INST:

36
src/core/arm/interpreter/armsupp.cpp
View file

@ -578,6 +578,42 @@ u16 ARMul_UnsignedSaturatedSub16(u16 left, u16 right)
return left - right;
}
// Signed saturation.
u32 ARMul_SignedSatQ(s32 value, u8 shift, bool* saturation_occurred)
{
const u32 max = (1 << shift) - 1;
const s32 top = (value >> shift);
if (top > 0) {
*saturation_occurred = true;
return max;
}
else if (top < -1) {
*saturation_occurred = true;
return ~max;
}
*saturation_occurred = false;
return (u32)value;
}
// Unsigned saturation
u32 ARMul_UnsignedSatQ(s32 value, u8 shift, bool* saturation_occurred)
{
const u32 max = (1 << shift) - 1;
if (value < 0) {
*saturation_occurred = true;
return 0;
} else if ((u32)value > max) {
*saturation_occurred = true;
return max;
}
*saturation_occurred = false;
return (u32)value;
}
/* 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

3
src/core/arm/skyeye_common/armdefs.h
View file

@ -801,6 +801,9 @@ extern u8 ARMul_UnsignedSaturatedSub8(u8, u8);
extern u16 ARMul_UnsignedSaturatedSub16(u16, u16);
extern u8 ARMul_UnsignedAbsoluteDifference(u8, u8);
extern u32 ARMul_SignedSatQ(s32, u8, bool*);
extern u32 ARMul_UnsignedSatQ(s32, u8, bool*);
#define DIFF_LOG 0
#define SAVE_LOG 0