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Merge pull request #9485 from JosJuice/jitarm64-pc-stp
JitArm64: Use STP for pc/npc
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degasus committed Feb 3, 2021
2 parents 7250d6e + dd8e504 commit b6e9cca
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Showing 2 changed files with 14 additions and 7 deletions.
@@ -452,13 +452,16 @@ void JitArm64::WriteExceptionExit(u32 destination, bool only_external)
MOVI2R(DISPATCHER_PC, destination);
FixupBranch no_exceptions = CBZ(W30);

STR(IndexType::Unsigned, DISPATCHER_PC, PPC_REG, PPCSTATE_OFF(pc));
STR(IndexType::Unsigned, DISPATCHER_PC, PPC_REG, PPCSTATE_OFF(npc));
static_assert(PPCSTATE_OFF(pc) <= 252);
static_assert(PPCSTATE_OFF(pc) + 4 == PPCSTATE_OFF(npc));
STP(IndexType::Signed, DISPATCHER_PC, DISPATCHER_PC, PPC_REG, PPCSTATE_OFF(pc));

if (only_external)
MOVP2R(X8, &PowerPC::CheckExternalExceptions);
else
MOVP2R(X8, &PowerPC::CheckExceptions);
BLR(X8);

LDR(IndexType::Unsigned, DISPATCHER_PC, PPC_REG, PPCSTATE_OFF(npc));

SetJumpTarget(no_exceptions);
@@ -479,13 +482,16 @@ void JitArm64::WriteExceptionExit(ARM64Reg dest, bool only_external)
LDR(IndexType::Unsigned, W30, PPC_REG, PPCSTATE_OFF(Exceptions));
FixupBranch no_exceptions = CBZ(W30);

STR(IndexType::Unsigned, DISPATCHER_PC, PPC_REG, PPCSTATE_OFF(pc));
STR(IndexType::Unsigned, DISPATCHER_PC, PPC_REG, PPCSTATE_OFF(npc));
static_assert(PPCSTATE_OFF(pc) <= 252);
static_assert(PPCSTATE_OFF(pc) + 4 == PPCSTATE_OFF(npc));
STP(IndexType::Signed, DISPATCHER_PC, DISPATCHER_PC, PPC_REG, PPCSTATE_OFF(pc));

if (only_external)
MOVP2R(EncodeRegTo64(DISPATCHER_PC), &PowerPC::CheckExternalExceptions);
else
MOVP2R(EncodeRegTo64(DISPATCHER_PC), &PowerPC::CheckExceptions);
BLR(EncodeRegTo64(DISPATCHER_PC));

LDR(IndexType::Unsigned, DISPATCHER_PC, PPC_REG, PPCSTATE_OFF(npc));

SetJumpTarget(no_exceptions);
@@ -102,12 +102,16 @@ static_assert(std::is_standard_layout<PairedSingle>(), "PairedSingle must be sta
//
// On AArch64, most load/store instructions support fairly large immediate offsets,
// but not LDP/STP, which we want to use for accessing certain things.
// These must be in the first 260 bytes: pc, npc
// These must be in the first 520 bytes: gather_pipe_ptr, gather_pipe_base_ptr
// Better code is generated if these are in the first 260 bytes: gpr
// Better code is generated if these are in the first 520 bytes: ps
// Unfortunately not all of those fit in 520 bytes, but we can fit most of ps and all of the rest.
struct PowerPCState
{
u32 pc; // program counter
u32 npc;

// gather pipe pointer for JIT access
u8* gather_pipe_ptr;
u8* gather_pipe_base_ptr;
@@ -121,9 +125,6 @@ struct PowerPCState
alignas(16) PairedSingle ps[32];
#endif

u32 pc; // program counter
u32 npc;

ConditionRegister cr;

UReg_MSR msr; // machine state register

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