Keep track of *which* input constraint matches an output

constraint.  Reject asms where an output has multiple
input constraints tied to it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57687 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 12 insertions, 6 deletions

diff --git a/include/llvm/InlineAsm.h b/include/llvm/InlineAsm.h
index 325b777dd4..879b2e847f 100644
--- a/include/llvm/InlineAsm.h
+++ b/include/llvm/InlineAsm.h
@@ -79,9 +79,15 @@ public:
     /// read.  This is only ever set for an output operand.
     bool isEarlyClobber; 
     
-    /// hasMatchingInput - This is set to true for an output constraint iff
-    /// there is an input constraint that is required to match it (e.g. "0").
-    bool hasMatchingInput;
+    /// MatchingInput - If this is not -1, this is an output constraint where an
+    /// input constraint is required to match it (e.g. "0").  The value is the
+    /// constraint number that matches this one (for example, if this is
+    /// constraint #0 and constraint #4 has the value "0", this will be 4).
+    signed char MatchingInput;
+    
+    /// hasMatchingInput - Return true if this is an output constraint that has
+    /// a matching input constraint.
+    bool hasMatchingInput() const { return MatchingInput != -1; }
     
     /// isCommutative - This is set to true for a constraint that is commutative
     /// with the next operand.
diff --git a/include/llvm/Target/TargetLowering.h b/include/llvm/Target/TargetLowering.h
index da4703c60d..5e5bdbe511 100644
--- a/include/llvm/Target/TargetLowering.h
+++ b/include/llvm/Target/TargetLowering.h
@@ -1197,9 +1197,9 @@ public:
     /// ConstraintVT - The ValueType for the operand value.
     MVT ConstraintVT;
     
-    /// isMatchingConstraint - Return true of this is an input operand that is a
-    /// matching constraint like "4".
-    bool isMatchingConstraint() const;
+    /// isMatchingInputConstraint - Return true of this is an input operand that
+    /// is a matching constraint like "4".
+    bool isMatchingInputConstraint() const;
     
     /// getMatchedOperand - If this is an input matching constraint, this method
     /// returns the output operand it matches.