Fix inline assembler constraint validation

The current constraint logic is both too lax and too strict. It fails
for input outside the [INT_MIN..INT_MAX] range, but it also implicitly
accepts 0 as value when it should not. Adjust logic to handle both
correctly.

Differential Revision: https://reviews.llvm.org/D58649


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@354937 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 4 deletions

diff --git a/include/clang/Basic/TargetInfo.h b/include/clang/Basic/TargetInfo.h
index 7a3dc3f60c..d41f4c6462 100644
--- a/include/clang/Basic/TargetInfo.h
+++ b/include/clang/Basic/TargetInfo.h
@@ -816,6 +816,7 @@ public:
     struct {
       int Min;
       int Max;
+      bool isConstrained;
     } ImmRange;
     llvm::SmallSet<int, 4> ImmSet;
 
@@ -826,6 +827,7 @@ public:
         : Flags(0), TiedOperand(-1), ConstraintStr(ConstraintStr.str()),
           Name(Name.str()) {
       ImmRange.Min = ImmRange.Max = 0;
+      ImmRange.isConstrained = false;
     }
 
     const std::string &getConstraintStr() const { return ConstraintStr; }
@@ -854,8 +856,9 @@ public:
       return (Flags & CI_ImmediateConstant) != 0;
     }
     bool isValidAsmImmediate(const llvm::APInt &Value) const {
-      return (Value.sge(ImmRange.Min) && Value.sle(ImmRange.Max)) ||
-             ImmSet.count(Value.getZExtValue()) != 0;
+      if (!ImmSet.empty())
+        return ImmSet.count(Value.getZExtValue()) != 0;
+      return !ImmRange.isConstrained || (Value.sge(ImmRange.Min) && Value.sle(ImmRange.Max));
     }
 
     void setIsReadWrite() { Flags |= CI_ReadWrite; }
@@ -867,6 +870,7 @@ public:
       Flags |= CI_ImmediateConstant;
       ImmRange.Min = Min;
       ImmRange.Max = Max;
+      ImmRange.isConstrained = true;
     }
     void setRequiresImmediate(llvm::ArrayRef<int> Exacts) {
       Flags |= CI_ImmediateConstant;
@@ -879,8 +883,6 @@ public:
     }
     void setRequiresImmediate() {
       Flags |= CI_ImmediateConstant;
-      ImmRange.Min = INT_MIN;
-      ImmRange.Max = INT_MAX;
     }
 
     /// Indicate that this is an input operand that is tied to