Fix PR8565.
This moves most of the isUsed logic to the MCSymbol itself. With this we
get a bit more relaxed about allowing definitions after uses: uses that
don't evaluate their argument immediately (jmp foo) are accepted.
ddunbar, this was the smallest compromise I could think of that lets us
accept gcc (and clang!) assembly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119144 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index 24b94d1..3632c93 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -485,9 +485,6 @@
std::pair<StringRef, StringRef> Split = Identifier.split('@');
MCSymbol *Sym = getContext().GetOrCreateSymbol(Split.first);
- // Mark the symbol as used in an expression.
- Sym->setUsedInExpr(true);
-
// Lookup the symbol variant if used.
MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
if (Split.first.size() != Identifier.size()) {
@@ -1191,6 +1188,25 @@
ActiveMacros.pop_back();
}
+static void MarkUsed(const MCExpr *Value) {
+ switch (Value->getKind()) {
+ case MCExpr::Binary:
+ MarkUsed(static_cast<const MCBinaryExpr*>(Value)->getLHS());
+ MarkUsed(static_cast<const MCBinaryExpr*>(Value)->getRHS());
+ break;
+ case MCExpr::Target:
+ case MCExpr::Constant:
+ break;
+ case MCExpr::SymbolRef: {
+ static_cast<const MCSymbolRefExpr*>(Value)->getSymbol().setUsed(true);
+ break;
+ }
+ case MCExpr::Unary:
+ MarkUsed(static_cast<const MCUnaryExpr*>(Value)->getSubExpr());
+ break;
+ }
+}
+
bool AsmParser::ParseAssignment(StringRef Name) {
// FIXME: Use better location, we should use proper tokens.
SMLoc EqualLoc = Lexer.getLoc();
@@ -1199,6 +1215,8 @@
if (ParseExpression(Value))
return true;
+ MarkUsed(Value);
+
if (Lexer.isNot(AsmToken::EndOfStatement))
return TokError("unexpected token in assignment");
@@ -1213,7 +1231,7 @@
//
// FIXME: Diagnostics. Note the location of the definition as a label.
// FIXME: Diagnose assignment to protected identifier (e.g., register name).
- if (Sym->isUndefined() && !Sym->isUsedInExpr())
+ if (Sym->isUndefined() && !Sym->isUsed() && !Sym->isVariable())
; // Allow redefinitions of undefined symbols only used in directives.
else if (!Sym->isUndefined() && !Sym->isAbsolute())
return Error(EqualLoc, "redefinition of '" + Name + "'");
@@ -1222,13 +1240,14 @@
else if (!isa<MCConstantExpr>(Sym->getVariableValue()))
return Error(EqualLoc, "invalid reassignment of non-absolute variable '" +
Name + "'");
+
+ // Don't count these checks as uses.
+ Sym->setUsed(false);
} else
Sym = getContext().GetOrCreateSymbol(Name);
// FIXME: Handle '.'.
- Sym->setUsedInExpr(true);
-
// Do the assignment.
Out.EmitAssignment(Sym, Value);