[SystemZ] Fix encoding of MVCK and .insn ss
LLVM currently treats the first operand of MVCK as if it were a
regular base+index+displacement address. However, it is in fact
a base+displacement combined with a length register field.
While the two might look syntactically similar, there are two
semantic differences:
- %r0 is a valid length register, even though it cannot be used
as an index register.
- In an expression with just a single register like 0(%rX), the
register is treated as base with normal addresses, while it is
treated as the length register (with an empty base) for MVCK.
Fixed by adding a new operand parser class BDRAddr and reworking
the assembler parser to distinguish between address + length
register operands and regular addresses.
llvm-svn: 285574
diff --git a/llvm/lib/Target/SystemZ/Disassembler/SystemZDisassembler.cpp b/llvm/lib/Target/SystemZ/Disassembler/SystemZDisassembler.cpp
index c82302d..71b81cd 100644
--- a/llvm/lib/Target/SystemZ/Disassembler/SystemZDisassembler.cpp
+++ b/llvm/lib/Target/SystemZ/Disassembler/SystemZDisassembler.cpp
@@ -321,6 +321,18 @@
return MCDisassembler::Success;
}
+static DecodeStatus decodeBDRAddr12Operand(MCInst &Inst, uint64_t Field,
+ const unsigned *Regs) {
+ uint64_t Length = Field >> 16;
+ uint64_t Base = (Field >> 12) & 0xf;
+ uint64_t Disp = Field & 0xfff;
+ assert(Length < 16 && "Invalid BDRAddr12");
+ Inst.addOperand(MCOperand::createReg(Base == 0 ? 0 : Regs[Base]));
+ Inst.addOperand(MCOperand::createImm(Disp));
+ Inst.addOperand(MCOperand::createReg(Regs[Length]));
+ return MCDisassembler::Success;
+}
+
static DecodeStatus decodeBDVAddr12Operand(MCInst &Inst, uint64_t Field,
const unsigned *Regs) {
uint64_t Index = Field >> 16;
@@ -376,6 +388,13 @@
return decodeBDLAddr12Len8Operand(Inst, Field, SystemZMC::GR64Regs);
}
+static DecodeStatus decodeBDRAddr64Disp12Operand(MCInst &Inst,
+ uint64_t Field,
+ uint64_t Address,
+ const void *Decoder) {
+ return decodeBDRAddr12Operand(Inst, Field, SystemZMC::GR64Regs);
+}
+
static DecodeStatus decodeBDVAddr64Disp12Operand(MCInst &Inst, uint64_t Field,
uint64_t Address,
const void *Decoder) {