Improvements to Sema of asm statements. Fixes <rdar://problem/6156893>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62609 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 31 insertions, 9 deletions

diff --git a/include/clang/Basic/DiagnosticKinds.def b/include/clang/Basic/DiagnosticKinds.def
index 2436727ea1..a43bbbb5ec 100644
--- a/include/clang/Basic/DiagnosticKinds.def
+++ b/include/clang/Basic/DiagnosticKinds.def
@@ -1466,10 +1466,12 @@ DIAG(err_asm_invalid_lvalue_in_output, ERROR,
     "invalid lvalue in asm output")
 DIAG(err_asm_invalid_output_constraint, ERROR,
     "invalid output constraint '%0' in asm")
+DIAG(err_asm_invalid_lvalue_in_input, ERROR,
+     "invalid lvalue in asm input for constraint '%0'")
 DIAG(err_asm_invalid_input_constraint, ERROR,
-    "invalid input constraint '%0' in asm")
+     "invalid input constraint '%0' in asm")
 DIAG(err_asm_invalid_type_in_input, ERROR,
-    "invalid type %0 in asm input for constraint '%1'")
+     "invalid type %0 in asm input for constraint '%1'")
 DIAG(err_asm_unknown_register_name, ERROR,
     "unknown register name '%0' in asm")
 DIAG(err_invalid_conversion_between_vectors, ERROR,
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 9e15c21f5a..4b89acb690 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -896,18 +896,27 @@ Sema::OwningStmtResult Sema::ActOnAsmStmt(SourceLocation AsmLoc,
                   diag::err_asm_invalid_input_constraint) << InputConstraint);
     }
 
-    // Check that the input exprs aren't of type void.
     ParenExpr *InputExpr = cast<ParenExpr>(Exprs[i]);
-    if (InputExpr->getType()->isVoidType()) {
 
-      return StmtError(Diag(InputExpr->getSubExpr()->getLocStart(),
-                  diag::err_asm_invalid_type_in_input)
-        << InputExpr->getType() << InputConstraint
-        << InputExpr->getSubExpr()->getSourceRange());
+    // Only allow void types for memory constraints.
+    if (info & TargetInfo::CI_AllowsMemory) {
+
+      if (InputExpr->isLvalue(Context) != Expr::LV_Valid)
+        return StmtError(Diag(InputExpr->getSubExpr()->getLocStart(),
+                              diag::err_asm_invalid_lvalue_in_input)
+          << InputConstraint << InputExpr->getSubExpr()->getSourceRange());
     }
 
-    if (info & TargetInfo::CI_AllowsRegister)
+    if (info & TargetInfo::CI_AllowsRegister) {
+      if (InputExpr->getType()->isVoidType()) {
+        return StmtError(Diag(InputExpr->getSubExpr()->getLocStart(),
+                              diag::err_asm_invalid_type_in_input)
+          << InputExpr->getType() << InputConstraint 
+          << InputExpr->getSubExpr()->getSourceRange());
+      }
+      
       DefaultFunctionArrayConversion(Exprs[i]);
+    }
   }
 
   // Check that the clobbers are valid.
diff --git a/test/Sema/asm.c b/test/Sema/asm.c
index 3bb7d78f5b..312b800ec7 100644
--- a/test/Sema/asm.c
+++ b/test/Sema/asm.c
@@ -37,3 +37,14 @@ void test3() {
   asm("foo" : L"=r"(x)); // expected-error {{wide string}}
 }
 
+// <rdar://problem/6156893>
+void test4(const volatile void *addr)
+{
+    asm ("nop" : : "r"(*addr)); // expected-error {{invalid type 'void const volatile' in asm input for constraint 'r'}}
+    asm ("nop" : : "m"(*addr));
+
+    asm ("nop" : : "r"(test4(addr))); // expected-error {{invalid type 'void' in asm input for constraint 'r'}}
+    asm ("nop" : : "m"(test4(addr))); // expected-error {{invalid lvalue in asm input for constraint 'm'}}
+
+    asm("nop" : : "m"(f())); // expected-error {{invalid lvalue in asm input for constraint 'm'}}
+}