If we have mismatched integer tied operands, but the operand
number is not mentioned in the asm string, let it past sema.
Right now these are currently rejected by the llvm code generator
but this will be fixed next.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70670 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 02f6840..d1246d2 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -1039,7 +1039,7 @@
if (!Info.hasTiedOperand()) continue;
unsigned TiedTo = Info.getTiedOperand();
- Expr *OutputExpr = Exprs[TiedTo];
+ Expr *OutputExpr = Exprs[TiedTo];
Expr *InputExpr = Exprs[i+NumOutputs];
QualType InTy = InputExpr->getType();
QualType OutTy = OutputExpr->getType();
@@ -1055,6 +1055,25 @@
// int*.
if (Context.getTypeSize(OutTy) == Context.getTypeSize(InTy))
continue;
+
+ // If the input and output operands are not mentioned in the asm string,
+ // then we can promote them and the asm string won't notice. Check this
+ // case now.
+ bool MentionedInput = false;
+ bool MentionedOutput = false;
+ for (unsigned i = 0, e = Pieces.size(); i != e; ++i) {
+ if (!Pieces[i].isOperand()) continue;
+ MentionedInput |= Pieces[i].getOperandNo() == i+NumOutputs;
+ MentionedOutput |= Pieces[i].getOperandNo() == TiedTo;
+ }
+
+ // If neither the input nor the output was mentioned in the asm string,
+ // and if the output was a register, just extend the shorter one to the
+ // size of the larger one.
+ // TODO: if only the larger one is mentioned, we could also support this.
+ if (!MentionedInput && !MentionedOutput &&
+ OutputConstraintInfos[TiedTo].allowsRegister())
+ continue;
}
Diag(InputExpr->getLocStart(),
diff --git a/test/Sema/asm.c b/test/Sema/asm.c
index 602b773..cc25fd8 100644
--- a/test/Sema/asm.c
+++ b/test/Sema/asm.c
@@ -73,6 +73,6 @@
// PR4077
int test7(unsigned long long b) {
int a;
- asm volatile("foo " : "=a" (a) :"0" (b)); // expected-error {{input with type 'unsigned long long' matching output with type 'int'}}
+ asm volatile("foo %0 %1" : "=a" (a) :"0" (b)); // expected-error {{input with type 'unsigned long long' matching output with type 'int'}}
return a;
}