JIT64: support merged branching for rlwinmx, too

Not quite as common a branch instruction as cmpwi, but close.
This commit is contained in:
Fiora 2014-08-17 23:12:16 -07:00
parent b56117de05
commit 8fc57d61ba
2 changed files with 120 additions and 98 deletions

View File

@ -106,6 +106,8 @@ public:
// Use to extract bytes from a register using the regcache. offset is in bytes.
Gen::OpArg ExtractFromReg(int reg, int offset);
void AndWithMask(Gen::X64Reg reg, u32 mask);
bool CheckMergedBranch(int crf);
void DoMergedBranch();
// Reads a given bit of a given CR register part.
void GetCRFieldBit(int field, int bit, Gen::X64Reg out, bool negate = false);

View File

@ -264,6 +264,54 @@ void Jit64::reg_imm(UGeckoInstruction inst)
}
}
bool Jit64::CheckMergedBranch(int crf)
{
const UGeckoInstruction& next = js.next_inst;
return (((next.OPCD == 16 /* bcx */) ||
((next.OPCD == 19) && (next.SUBOP10 == 528) /* bcctrx */) ||
((next.OPCD == 19) && (next.SUBOP10 == 16) /* bclrx */)) &&
(next.BO & BO_DONT_DECREMENT_FLAG) &&
!(next.BO & BO_DONT_CHECK_CONDITION) &&
(next.BI >> 2) == crf);
}
void Jit64::DoMergedBranch()
{
// Code that handles successful PPC branching.
if (js.next_inst.OPCD == 16) // bcx
{
if (js.next_inst.LK)
MOV(32, M(&LR), Imm32(js.next_compilerPC + 4));
u32 destination;
if (js.next_inst.AA)
destination = SignExt16(js.next_inst.BD << 2);
else
destination = js.next_compilerPC + SignExt16(js.next_inst.BD << 2);
WriteExit(destination);
}
else if ((js.next_inst.OPCD == 19) && (js.next_inst.SUBOP10 == 528)) // bcctrx
{
if (js.next_inst.LK)
MOV(32, M(&LR), Imm32(js.next_compilerPC + 4));
MOV(32, R(RSCRATCH), M(&CTR));
AND(32, R(RSCRATCH), Imm32(0xFFFFFFFC));
WriteExitDestInRSCRATCH();
}
else if ((js.next_inst.OPCD == 19) && (js.next_inst.SUBOP10 == 16)) // bclrx
{
MOV(32, R(RSCRATCH), M(&LR));
AND(32, R(RSCRATCH), Imm32(0xFFFFFFFC));
if (js.next_inst.LK)
MOV(32, M(&LR), Imm32(js.next_compilerPC + 4));
WriteExitDestInRSCRATCH();
}
else
{
PanicAlert("WTF invalid branch");
}
}
void Jit64::cmpXX(UGeckoInstruction inst)
{
// USES_CR
@ -272,23 +320,7 @@ void Jit64::cmpXX(UGeckoInstruction inst)
int a = inst.RA;
int b = inst.RB;
int crf = inst.CRFD;
bool merge_branch = false;
int test_crf = js.next_inst.BI >> 2;
// Check if the next instruction is a branch - if it is, merge the two.
if (((js.next_inst.OPCD == 16 /* bcx */) ||
((js.next_inst.OPCD == 19) && (js.next_inst.SUBOP10 == 528) /* bcctrx */) ||
((js.next_inst.OPCD == 19) && (js.next_inst.SUBOP10 == 16) /* bclrx */)) &&
(js.next_inst.BO & BO_DONT_DECREMENT_FLAG) &&
!(js.next_inst.BO & BO_DONT_CHECK_CONDITION))
{
// Looks like a decent conditional branch that we can merge with.
// It only test CR, not CTR.
if (test_crf == crf)
{
merge_branch = true;
}
}
bool merge_branch = CheckMergedBranch(crf);
OpArg comparand;
bool signedCompare;
@ -358,47 +390,13 @@ void Jit64::cmpXX(UGeckoInstruction inst)
{
gpr.Flush();
fpr.Flush();
if (js.next_inst.OPCD == 16) // bcx
{
if (js.next_inst.LK)
MOV(32, PPCSTATE_LR, Imm32(js.next_compilerPC + 4));
u32 destination;
if (js.next_inst.AA)
destination = SignExt16(js.next_inst.BD << 2);
else
destination = js.next_compilerPC + SignExt16(js.next_inst.BD << 2);
WriteExit(destination);
}
else if ((js.next_inst.OPCD == 19) && (js.next_inst.SUBOP10 == 528)) // bcctrx
{
if (js.next_inst.LK)
MOV(32, PPCSTATE_LR, Imm32(js.next_compilerPC + 4));
MOV(32, R(RSCRATCH), PPCSTATE_CTR);
AND(32, R(RSCRATCH), Imm32(0xFFFFFFFC));
WriteExitDestInRSCRATCH();
}
else if ((js.next_inst.OPCD == 19) && (js.next_inst.SUBOP10 == 16)) // bclrx
{
MOV(32, R(RSCRATCH), PPCSTATE_LR);
if (js.next_inst.LK)
MOV(32, PPCSTATE_LR, Imm32(js.next_compilerPC + 4));
WriteExitDestInRSCRATCH();
}
else
{
PanicAlert("WTF invalid branch");
}
DoMergedBranch();
}
else
else if (!analyzer.HasOption(PPCAnalyst::PPCAnalyzer::OPTION_CONDITIONAL_CONTINUE))
{
if (!analyzer.HasOption(PPCAnalyst::PPCAnalyzer::OPTION_CONDITIONAL_CONTINUE))
{
gpr.Flush();
fpr.Flush();
WriteExit(js.next_compilerPC + 4);
}
gpr.Flush();
fpr.Flush();
WriteExit(js.next_compilerPC + 4);
}
}
}
@ -487,51 +485,12 @@ void Jit64::cmpXX(UGeckoInstruction inst)
gpr.Flush(FLUSH_MAINTAIN_STATE);
fpr.Flush(FLUSH_MAINTAIN_STATE);
// Code that handles successful PPC branching.
if (js.next_inst.OPCD == 16) // bcx
{
if (js.next_inst.LK)
MOV(32, PPCSTATE_LR, Imm32(js.next_compilerPC + 4));
u32 destination;
if (js.next_inst.AA)
destination = SignExt16(js.next_inst.BD << 2);
else
destination = js.next_compilerPC + SignExt16(js.next_inst.BD << 2);
WriteExit(destination);
}
else if ((js.next_inst.OPCD == 19) && (js.next_inst.SUBOP10 == 528)) // bcctrx
{
if (js.next_inst.LK)
MOV(32, PPCSTATE_LR, Imm32(js.next_compilerPC + 4));
MOV(32, R(RSCRATCH), PPCSTATE_CTR);
AND(32, R(RSCRATCH), Imm32(0xFFFFFFFC));
WriteExitDestInRSCRATCH();
}
else if ((js.next_inst.OPCD == 19) && (js.next_inst.SUBOP10 == 16)) // bclrx
{
MOV(32, R(RSCRATCH), PPCSTATE_LR);
AND(32, R(RSCRATCH), Imm32(0xFFFFFFFC));
if (js.next_inst.LK)
MOV(32, PPCSTATE_LR, Imm32(js.next_compilerPC + 4));
WriteExitDestInRSCRATCH();
}
else
{
PanicAlert("WTF invalid branch");
}
DoMergedBranch();
SetJumpTarget(pDontBranch);
if (!analyzer.HasOption(PPCAnalyst::PPCAnalyzer::OPTION_CONDITIONAL_CONTINUE))
{
gpr.Flush();
fpr.Flush();
WriteExit(js.next_compilerPC + 4);
}
}
}
@ -1494,6 +1453,11 @@ void Jit64::rlwinmx(UGeckoInstruction inst)
JITDISABLE(bJITIntegerOff);
int a = inst.RA;
int s = inst.RS;
// rlwinm is commonly used as a branch test, second only to the more obvious cmpw.
// since it's almost never used with any check other than beq, only support beq for simplicity.
bool merge_branch = inst.Rc && CheckMergedBranch(0) && (js.next_inst.BI & 3) == 2;
if (gpr.R(s).IsImm())
{
u32 result = (int)gpr.R(s).offset;
@ -1510,6 +1474,11 @@ void Jit64::rlwinmx(UGeckoInstruction inst)
bool right_shift = inst.SH && inst.ME == 31 && inst.MB == 32 - inst.SH;
u32 mask = Helper_Mask(inst.MB, inst.ME);
bool simple_mask = mask == 0xff || mask == 0xffff;
// in case of a merged branch, track whether or not we've set flags.
// if not, we need to do a TEST later to get them.
bool needs_test = false;
// if we know the high bit can't be set, we can avoid doing a sign extend for flag storage
bool needs_sext = true;
int mask_size = inst.ME - inst.MB + 1;
gpr.Lock(a, s);
@ -1517,11 +1486,14 @@ void Jit64::rlwinmx(UGeckoInstruction inst)
if (a != s && left_shift && gpr.R(s).IsSimpleReg() && inst.SH <= 3)
{
LEA(32, gpr.RX(a), MScaled(gpr.RX(s), SCALE_1 << inst.SH, 0));
needs_test = true;
}
// common optimized case: byte/word extract
else if (simple_mask && !(inst.SH & (mask_size - 1)))
{
MOVZX(32, mask_size, gpr.RX(a), ExtractFromReg(s, inst.SH ? (32 - inst.SH) >> 3 : 0));
needs_test = true;
needs_sext = false;
}
// another optimized special case: byte/word extract plus shift
else if (((mask >> inst.SH) << inst.SH) == mask && !left_shift &&
@ -1529,6 +1501,7 @@ void Jit64::rlwinmx(UGeckoInstruction inst)
{
MOVZX(32, mask_size, gpr.RX(a), gpr.R(s));
SHL(32, gpr.R(a), Imm8(inst.SH));
needs_sext = inst.SH + mask_size >= 32;
}
else
{
@ -1542,17 +1515,64 @@ void Jit64::rlwinmx(UGeckoInstruction inst)
else if (right_shift)
{
SHR(32, gpr.R(a), Imm8(inst.MB));
needs_sext = false;
}
else
{
if (inst.SH != 0)
ROL(32, gpr.R(a), Imm8(inst.SH));
if (!(inst.MB == 0 && inst.ME == 31))
AndWithMask(gpr.RX(a), mask);
{
// we need flags if we're merging the branch
if (merge_branch)
AND(32, gpr.R(a), Imm32(mask));
else
AndWithMask(gpr.RX(a), mask);
needs_sext = inst.MB == 0;
}
else
{
needs_test = true;
}
}
}
if (inst.Rc)
if (merge_branch)
{
js.downcountAmount++;
js.skipnext = true;
if (needs_sext)
{
MOVSX(64, 32, RSCRATCH, gpr.R(a));
MOV(64, M(&PowerPC::ppcState.cr_val[0]), R(RSCRATCH));
}
else
{
MOV(64, M(&PowerPC::ppcState.cr_val[0]), gpr.R(a));
}
if (needs_test)
TEST(32, gpr.R(a), gpr.R(a));
gpr.UnlockAll();
FixupBranch dont_branch = J_CC((js.next_inst.BO & BO_BRANCH_IF_TRUE) ? CC_NE : CC_E, true);
gpr.Flush(FLUSH_MAINTAIN_STATE);
fpr.Flush(FLUSH_MAINTAIN_STATE);
DoMergedBranch();
SetJumpTarget(dont_branch);
if (!analyzer.HasOption(PPCAnalyst::PPCAnalyzer::OPTION_CONDITIONAL_CONTINUE))
{
gpr.Flush();
fpr.Flush();
WriteExit(js.next_compilerPC + 4);
}
}
else if (inst.Rc)
{
ComputeRC(gpr.R(a));
}
gpr.UnlockAll();
}
}