[mips] Show an error if register number is out of range
Current code does not check that a register number is in the 0-31 range.
Sometimes the parser checks that later for some kinds of instructions,
but that leads to unclear / incorrect error messages like that:
% cat test.s
.text
lb $4, 8($32)
% llvm-mc test.s -triple=mips64-unknown-linux
test.s:2:10: error: expected memory with 16-bit signed offset
lb $4, 8($32)
^
Sometimes the parser just crashes:
% cat test.s
.text
lw $4, 8($32)
% llvm-mc test.s -triple=mips64-unknown-linux
This patch resolves the problem by checking that register number after
'$' sign is in the 0-31 range. If the number is out of the range the
parser shows the `invalid register number` error, but treats invalid
register number as a normal one to continue parsing and catch other
possible errors.
Differential Revision: https://reviews.llvm.org/D45919
llvm-svn: 330732
diff --git a/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp b/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
index f7467e9..869e037 100644
--- a/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ b/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -6029,8 +6029,15 @@
return ResTy;
} else if (Token.is(AsmToken::Integer)) {
DEBUG(dbgs() << ".. integer\n");
+ int64_t RegNum = Token.getIntVal();
+ if (RegNum < 0 || RegNum > 31) {
+ // Show the error, but treat invalid register
+ // number as a normal one to continue parsing
+ // and catch other possible errors.
+ Error(getLexer().getLoc(), "invalid register number");
+ }
Operands.push_back(MipsOperand::createNumericReg(
- Token.getIntVal(), Token.getString(), getContext().getRegisterInfo(), S,
+ RegNum, Token.getString(), getContext().getRegisterInfo(), S,
Token.getLoc(), *this));
return MatchOperand_Success;
}