From a0b9ce03880b7dbab766ec80817eb17a20eba508 Mon Sep 17 00:00:00 2001 From: Bill Wendling Date: Thu, 25 Oct 2012 00:05:55 +0000 Subject: [PATCH] Add some support for diagnosing possibly mismatched constraint, type size and modifiers. (From an idea by Eric...) git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166647 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/clang/Basic/DiagnosticSemaKinds.td | 3 ++ include/clang/Basic/TargetInfo.h | 5 +++ lib/Basic/Targets.cpp | 23 +++++++++++ lib/Sema/SemaStmtAsm.cpp | 48 ++++++++++++++++++++++ test/Misc/warning-flags.c | 3 +- 5 files changed, 81 insertions(+), 1 deletion(-) diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td index 56cb206042..cd7fb00c99 100644 --- a/include/clang/Basic/DiagnosticSemaKinds.td +++ b/include/clang/Basic/DiagnosticSemaKinds.td @@ -5146,6 +5146,9 @@ let CategoryName = "Inline Assembly Issue" in { "invalid use of a cast in a inline asm context requiring an l-value: " "accepted due to -fheinous-gnu-extensions, but clang may remove support " "for this in the future">; + def warn_mismatched_size_modifier : Warning< + "the size being stored may not be the size intended, use a modifier to " + "specify the size">; def err_inline_ms_asm_parsing : Error<"%0">; } diff --git a/include/clang/Basic/TargetInfo.h b/include/clang/Basic/TargetInfo.h index ea520e8f82..b0e58050d5 100644 --- a/include/clang/Basic/TargetInfo.h +++ b/include/clang/Basic/TargetInfo.h @@ -517,6 +517,11 @@ public: bool validateInputConstraint(ConstraintInfo *OutputConstraints, unsigned NumOutputs, ConstraintInfo &info) const; + virtual bool validateConstraintModifier(StringRef /*Constraint*/, + const char /*Modifier*/, + unsigned /*Size*/) const { + return true; + } bool resolveSymbolicName(const char *&Name, ConstraintInfo *OutputConstraints, unsigned NumOutputs, unsigned &Index) const; diff --git a/lib/Basic/Targets.cpp b/lib/Basic/Targets.cpp index ba96185f72..960a2858e4 100644 --- a/lib/Basic/Targets.cpp +++ b/lib/Basic/Targets.cpp @@ -3315,6 +3315,29 @@ public: } return R; } + virtual bool validateConstraintModifier(StringRef Constraint, + const char Modifier, + unsigned Size) const { + // Strip off constraint modifiers. + while (Constraint[0] == '=' || + Constraint[0] == '+' || + Constraint[0] == '&') + Constraint = Constraint.substr(1); + + switch (Constraint[0]) { + default: break; + case 'r': { + switch (Modifier) { + default: return Size == 32; + case 'q': + // A register of size 32 cannot fit a vector type. + return false; + } + } + } + + return true; + } virtual const char *getClobbers() const { // FIXME: Is this really right? return ""; diff --git a/lib/Sema/SemaStmtAsm.cpp b/lib/Sema/SemaStmtAsm.cpp index 3a5f40c74f..138d671470 100644 --- a/lib/Sema/SemaStmtAsm.cpp +++ b/lib/Sema/SemaStmtAsm.cpp @@ -208,6 +208,54 @@ StmtResult Sema::ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple, return StmtError(); } + // Validate constraints and modifiers. + for (unsigned i = 0, e = Pieces.size(); i != e; ++i) { + GCCAsmStmt::AsmStringPiece &Piece = Pieces[i]; + if (!Piece.isOperand()) continue; + + // Look for the correct constraint index. + unsigned Idx = 0; + unsigned ConstraintIdx = 0; + for (unsigned i = 0, e = NS->getNumOutputs(); i != e; ++i, ++ConstraintIdx) { + TargetInfo::ConstraintInfo &Info = OutputConstraintInfos[i]; + if (Idx == Piece.getOperandNo()) + break; + ++Idx; + + if (Info.isReadWrite()) { + if (Idx == Piece.getOperandNo()) + break; + ++Idx; + } + } + + for (unsigned i = 0, e = NS->getNumInputs(); i != e; ++i, ++ConstraintIdx) { + TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i]; + if (Idx == Piece.getOperandNo()) + break; + ++Idx; + + if (Info.isReadWrite()) { + if (Idx == Piece.getOperandNo()) + break; + ++Idx; + } + } + + // Now that we have the right indexes go ahead and check. + StringLiteral *Literal = Constraints[ConstraintIdx]; + const Type *Ty = Exprs[ConstraintIdx]->getType().getTypePtr(); + if (Ty->isDependentType() || Ty->isIncompleteType()) + continue; + + unsigned Size = Context.getTypeSize(Ty); + if (!Context.getTargetInfo() + .validateConstraintModifier(Literal->getString(), + Piece.getModifier(), Size)) + Diag(Exprs[ConstraintIdx]->getLocStart(), + diag::warn_mismatched_size_modifier); + } + // Validate tied input operands for type mismatches. for (unsigned i = 0, e = InputConstraintInfos.size(); i != e; ++i) { TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i]; diff --git a/test/Misc/warning-flags.c b/test/Misc/warning-flags.c index 302abccc59..fa73db11d8 100644 --- a/test/Misc/warning-flags.c +++ b/test/Misc/warning-flags.c @@ -18,7 +18,7 @@ This test serves two purposes: The list of warnings below should NEVER grow. It should gradually shrink to 0. -CHECK: Warnings without flags (154): +CHECK: Warnings without flags (155): CHECK-NEXT: ext_delete_void_ptr_operand CHECK-NEXT: ext_enum_friend CHECK-NEXT: ext_expected_semi_decl_list @@ -100,6 +100,7 @@ CHECK-NEXT: warn_many_braces_around_scalar_init CHECK-NEXT: warn_maynot_respond CHECK-NEXT: warn_method_param_redefinition CHECK-NEXT: warn_mismatched_exception_spec +CHECK-NEXT: warn_mismatched_size_modifier CHECK-NEXT: warn_missing_case_for_condition CHECK-NEXT: warn_missing_dependent_template_keyword CHECK-NEXT: warn_missing_exception_specification -- 2.40.0