This fixes https://github.com/dotnet/coreclr/issues/3738.
The fix I made in
https://github.com/dotnet/coreclr/commit/
4dfd323dab88b902fc9479efa60cb5d6b7659e94
used 3rd/4th operand to keep GC info, which actually conflicts with
address field which is unioned with these operands.
So, I go back to the original fix that I proposed below:
Indirect call (```br``` or ```blr```) target is encoded with a register
which the first operand internally represents.
Unfortunately, call sites use the first two operands to hold GC callee-save registers.
So, this GC register information was overridden by the call target operand
in the indirect(virtual) call sites.
The fix is to split branch instruction categories for these two instructions
while keeping ```ret``` same as before. They internally use the third
operand to encode the target since the first two are used for GC info.
The reason I didn't change ```ret``` is because the return instruction
is created as a small instruction (not using operand 3 and more).
iiaEncodedInstrCount = (count << iaut_SHIFT) | iaut_INST_COUNT;
}
- // Note that we use the _idReg3 and _idReg4 fields to hold
- // the live gcrefReg mask for the call instructions on arm64
- //
struct
{
regNumber _idReg3 :REGNUM_BITS;
assert(isGeneralRegister(id->idReg1()));
break;
+ case IF_BR_1B: // BR_1B ................ ......nnnnn..... Rn
+ assert(isGeneralRegister(id->idReg3()));
+ break;
+
case IF_LS_1A: // LS_1A .X......iiiiiiii iiiiiiiiiiittttt Rt PC imm(1MB)
assert(isGeneralRegister(id->idReg1()) ||
isVectorRegister(id->idReg1()));
case IF_BI_1A:
case IF_BI_1B:
case IF_BR_1A:
+ case IF_BR_1B:
case IF_LS_1A:
case IF_LS_2A:
case IF_LS_2B:
case INS_br:
assert(isGeneralRegister(reg));
id = emitNewInstrCns(attr, 0);
- fmt = IF_BR_1A;
+ id->idReg3(reg);
+ fmt = IF_BR_1B;
break;
case INS_ret:
assert(isGeneralRegister(reg));
id = emitNewInstrSmall(attr);
+ id->idReg1(reg);
fmt = IF_BR_1A;
break;
default:
- // TODO-Cleanup: add unreached() here
- break;
-
+ unreached();
}
+
assert(fmt != IF_NONE);
- if (id != nullptr)
- {
- id->idIns(ins);
- id->idInsFmt(fmt);
- id->idReg1(reg);
+ id->idIns(ins);
+ id->idInsFmt(fmt);
+
+ dispIns(id);
+ appendToCurIG(id);
- dispIns(id);
- appendToCurIG(id);
- }
}
/*****************************************************************************
{
ins = INS_blr; // INS_blr Reg
}
- fmt = IF_BR_1A;
+ fmt = IF_BR_1B;
id->idIns(ins);
id->idInsFmt(fmt);
- id->idReg1(ireg);
+ id->idReg3(ireg);
assert(xreg == REG_NA);
break;
case IF_BR_1A: // BR_1A ................ ......nnnnn..... Rn
assert(insOptsNone(id->idInsOpt()));
+ assert(ins == INS_ret);
code = emitInsCode(ins, fmt);
code |= insEncodeReg_Rn(id->idReg1()); // nnnnn
- if (ins == INS_ret)
- {
- dst += emitOutput_Instr(dst, code);
- }
- else // INS_blr or INS_br
- {
- sz = id->idIsLargeCall() ? sizeof(instrDescCGCA) : sizeof(instrDesc);
- dst += emitOutputCall(ig, dst, id, code);
- }
+ dst += emitOutput_Instr(dst, code);
+ break;
+
+ case IF_BR_1B: // BR_1B ................ ......nnnnn..... Rn
+ assert(insOptsNone(id->idInsOpt()));
+ assert(ins != INS_ret);
+ code = emitInsCode(ins, fmt);
+ code |= insEncodeReg_Rn(id->idReg3()); // nnnnn
+
+ sz = id->idIsLargeCall() ? sizeof(instrDescCGCA) : sizeof(instrDesc);
+ dst += emitOutputCall(ig, dst, id, code);
break;
case IF_LS_1A: // LS_1A XX......iiiiiiii iiiiiiiiiiittttt Rt PC imm(1MB)
emitDispReg(id->idReg1(), size, false);
break;
+ case IF_BR_1B: // BR_1B ................ ......nnnnn..... Rn
+ assert(insOptsNone(id->idInsOpt()));
+ emitDispReg(id->idReg3(), size, false);
+ break;
+
case IF_LS_1A: // LS_1A XX......iiiiiiii iiiiiiiiiiittttt Rt PC imm(1MB)
assert(insOptsNone(id->idInsOpt()));
emitDispReg(id->idReg1(), size, true);
IF_DEF(BI_0C, IS_NONE, CALL) // BI_0C ......iiiiiiiiii iiiiiiiiiiiiiiii simm26:00 bl
IF_DEF(BI_1A, IS_NONE, JMP) // BI_1A X.......iiiiiiii iiiiiiiiiiittttt Rt simm19:00 cbz cbnz
IF_DEF(BI_1B, IS_NONE, JMP) // BI_1B B.......bbbbbiii iiiiiiiiiiittttt Rt imm6 simm14:00 tbz tbnz
-IF_DEF(BR_1A, IS_NONE, CALL) // BR_1A ................ ......nnnnn..... Rn br blr ret
+IF_DEF(BR_1A, IS_NONE, CALL) // BR_1A ................ ......nnnnn..... Rn ret
+IF_DEF(BR_1B, IS_NONE, CALL) // BR_1B ................ ......nnnnn..... Rn br blr
IF_DEF(LS_1A, IS_NONE, JMP) // LS_1A .X......iiiiiiii iiiiiiiiiiittttt Rt PC imm(1MB)
IF_DEF(LS_2A, IS_NONE, NONE) // LS_2A .X.......X...... ......nnnnnttttt Rt Rn
if ((regmask & RBM_R23) != RBM_NONE)
encodeMask |= 0x10;
- id->idReg3((regNumber)encodeMask); // Save in idReg3
+ id->idReg1((regNumber)encodeMask); // Save in idReg1
encodeMask = 0;
if ((regmask & RBM_R28) != RBM_NONE)
encodeMask |= 0x10;
- id->idReg4((regNumber)encodeMask); // Save in idReg4
+ id->idReg2((regNumber)encodeMask); // Save in idReg2
#else
NYI("unknown target");
#elif defined(_TARGET_ARM64_)
assert(REGNUM_BITS >= 5);
- encodeMask = id->idReg3();
+ encodeMask = id->idReg1();
if ((encodeMask & 0x01) != 0)
regmask |= RBM_R19;
if ((encodeMask & 0x10) != 0)
regmask |= RBM_R23;
- encodeMask = id->idReg4();
+ encodeMask = id->idReg2();
if ((encodeMask & 0x01) != 0)
regmask |= RBM_R24;
INST1(bl, "bl", 0, 0, IF_BI_0C, 0x94000000)
// bl simm26 BI_0C 100101iiiiiiiiii iiiiiiiiiiiiiiii 9400 0000 simm26:00
-INST1(br, "br", 0, 0, IF_BR_1A, 0xD61F0000)
- // br Rn BR_1A 1101011000011111 000000nnnnn00000 D61F 0000
-
-INST1(blr, "blr", 0, 0, IF_BR_1A, 0xD63F0000)
- // blr Rn BR_1A 1101011000111111 000000nnnnn00000 D63F 0000
-
+INST1(br, "br", 0, 0, IF_BR_1B, 0xD61F0000)
+ // br Rn BR_1B 1101011000011111 000000nnnnn00000 D61F 0000
+
+INST1(blr, "blr", 0, 0, IF_BR_1B, 0xD63F0000)
+ // blr Rn BR_1B 1101011000111111 000000nnnnn00000 D63F 0000
+
INST1(ret, "ret", 0, 0, IF_BR_1A, 0xD65F0000)
- // ret Rn BR_1A 1101011001011111 000000nnnnn00000 D65F 0000
-
+ // ret Rn BR_1A 1101011001011111 000000nnnnn00000 D65F 0000
+
INST1(beq, "beq", 0, 0, IF_BI_0B, 0x54000000)
// beq simm19 BI_0B 01010100iiiiiiii iiiiiiiiiii00000 5400 0000 simm19:00