ms-inline-asm: Scope inline asm labels to functions
Summary:
This fixes PR20023. In order to implement this scoping rule, we piggy
back on the existing LabelDecl machinery, by creating LabelDecl's that
will carry the "internal" name of the inline assembly label, which we
will rewrite the asm label to.
Reviewers: rnk
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4589
llvm-svn: 218230
diff --git a/clang/lib/Sema/JumpDiagnostics.cpp b/clang/lib/Sema/JumpDiagnostics.cpp
index 2558452..fd75c02 100644
--- a/clang/lib/Sema/JumpDiagnostics.cpp
+++ b/clang/lib/Sema/JumpDiagnostics.cpp
@@ -84,6 +84,7 @@
void CheckJump(Stmt *From, Stmt *To, SourceLocation DiagLoc,
unsigned JumpDiag, unsigned JumpDiagWarning,
unsigned JumpDiagCXX98Compat);
+ void CheckGotoStmt(GotoStmt *GS);
unsigned GetDeepestCommonScope(unsigned A, unsigned B);
};
@@ -489,10 +490,14 @@
// With a goto,
if (GotoStmt *GS = dyn_cast<GotoStmt>(Jump)) {
- CheckJump(GS, GS->getLabel()->getStmt(), GS->getGotoLoc(),
- diag::err_goto_into_protected_scope,
- diag::ext_goto_into_protected_scope,
- diag::warn_cxx98_compat_goto_into_protected_scope);
+ // The label may not have a statement if it's coming from inline MS ASM.
+ if (GS->getLabel()->getStmt()) {
+ CheckJump(GS, GS->getLabel()->getStmt(), GS->getGotoLoc(),
+ diag::err_goto_into_protected_scope,
+ diag::ext_goto_into_protected_scope,
+ diag::warn_cxx98_compat_goto_into_protected_scope);
+ }
+ CheckGotoStmt(GS);
continue;
}
@@ -789,6 +794,15 @@
}
}
+void JumpScopeChecker::CheckGotoStmt(GotoStmt *GS) {
+ if (GS->getLabel()->isMSAsmLabel()) {
+ S.Diag(GS->getGotoLoc(), diag::err_goto_ms_asm_label)
+ << GS->getLabel()->getIdentifier();
+ S.Diag(GS->getLabel()->getLocation(), diag::note_goto_ms_asm_label)
+ << GS->getLabel()->getIdentifier();
+ }
+}
+
void Sema::DiagnoseInvalidJumps(Stmt *Body) {
(void)JumpScopeChecker(Body, *this);
}
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 69a4356..7ecd416 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -98,6 +98,7 @@
InitDictionaryWithObjectsMethod(nullptr),
ArrayAllocObjectsMethod(nullptr),
DictAllocObjectsMethod(nullptr),
+ MSAsmLabelNameCounter(0),
GlobalNewDeleteDeclared(false),
TUKind(TUKind),
NumSFINAEErrors(0),
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 535e33a..ae79720 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -1517,8 +1517,14 @@
static void CheckPoppedLabel(LabelDecl *L, Sema &S) {
// Verify that we have no forward references left. If so, there was a goto
// or address of a label taken, but no definition of it. Label fwd
- // definitions are indicated with a null substmt.
- if (L->getStmt() == nullptr)
+ // definitions are indicated with a null substmt which is also not a resolved
+ // MS inline assembly label name.
+ bool Diagnose = false;
+ if (L->isMSAsmLabel())
+ Diagnose = !L->isResolvedMSAsmLabel();
+ else
+ Diagnose = L->getStmt() == nullptr;
+ if (Diagnose)
S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName();
}
diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
index 8d2a325..464206e 100644
--- a/clang/lib/Sema/SemaStmt.cpp
+++ b/clang/lib/Sema/SemaStmt.cpp
@@ -432,7 +432,11 @@
TheDecl->setStmt(LS);
if (!TheDecl->isGnuLocal()) {
TheDecl->setLocStart(IdentLoc);
- TheDecl->setLocation(IdentLoc);
+ if (!TheDecl->isMSAsmLabel()) {
+ // Don't update the location of MS ASM labels. These will result in
+ // a diagnostic, and changing the location here will mess that up.
+ TheDecl->setLocation(IdentLoc);
+ }
}
return LS;
}
diff --git a/clang/lib/Sema/SemaStmtAsm.cpp b/clang/lib/Sema/SemaStmtAsm.cpp
index 5aa1a2c..dc50e87 100644
--- a/clang/lib/Sema/SemaStmtAsm.cpp
+++ b/clang/lib/Sema/SemaStmtAsm.cpp
@@ -15,6 +15,7 @@
#include "clang/AST/RecordLayout.h"
#include "clang/AST/TypeLoc.h"
#include "clang/Basic/TargetInfo.h"
+#include "clang/Lex/Preprocessor.h"
#include "clang/Sema/Initialization.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/Scope.h"
@@ -520,6 +521,7 @@
ArrayRef<Expr*> Exprs,
SourceLocation EndLoc) {
bool IsSimple = (NumOutputs != 0 || NumInputs != 0);
+ getCurFunction()->setHasBranchProtectedScope();
MSAsmStmt *NS =
new (Context) MSAsmStmt(Context, AsmLoc, LBraceLoc, IsSimple,
/*IsVolatile*/ true, AsmToks, NumOutputs, NumInputs,
@@ -527,3 +529,31 @@
Clobbers, EndLoc);
return NS;
}
+
+LabelDecl *Sema::GetOrCreateMSAsmLabel(StringRef ExternalLabelName,
+ SourceLocation Location,
+ bool AlwaysCreate) {
+ LabelDecl* Label = LookupOrCreateLabel(PP.getIdentifierInfo(ExternalLabelName),
+ Location);
+
+ if (!Label->isMSAsmLabel()) {
+ // Otherwise, insert it, but only resolve it if we have seen the label itself.
+ std::string InternalName;
+ llvm::raw_string_ostream OS(InternalName);
+ // Create an internal name for the label. The name should not be a valid mangled
+ // name, and should be unique. We use a dot to make the name an invalid mangled
+ // name.
+ OS << "__MSASMLABEL_." << MSAsmLabelNameCounter++ << "__" << ExternalLabelName;
+ Label->setMSAsmLabel(OS.str());
+ }
+ if (AlwaysCreate) {
+ // The label might have been created implicitly from a previously encountered
+ // goto statement. So, for both newly created and looked up labels, we mark
+ // them as resolved.
+ Label->setMSAsmLabelResolved();
+ }
+ // Adjust their location for being able to generate accurate diagnostics.
+ Label->setLocation(Location);
+
+ return Label;
+}