Inline asm multiple alternative constraints development phase 2 - improved basic logic, added initial platform support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117667 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 37 insertions, 19 deletions

diff --git a/include/llvm/CodeGen/Analysis.h b/include/llvm/CodeGen/Analysis.h
index ee2e520..a8292ea 100644
--- a/include/llvm/CodeGen/Analysis.h
+++ b/include/llvm/CodeGen/Analysis.h
@@ -52,7 +52,7 @@ GlobalVariable *ExtractTypeInfo(Value *V);
 
 /// hasInlineAsmMemConstraint - Return true if the inline asm instruction being
 /// processed uses a memory 'm' constraint.
-bool hasInlineAsmMemConstraint(std::vector<InlineAsm::ConstraintInfo> &CInfos,
+bool hasInlineAsmMemConstraint(InlineAsm::ConstraintInfoVector &CInfos,
                                const TargetLowering &TLI);
 
 /// getFCmpCondCode - Return the ISD condition code corresponding to
diff --git a/include/llvm/InlineAsm.h b/include/llvm/InlineAsm.h
index 0cb55b7..9343834 100644
--- a/include/llvm/InlineAsm.h
+++ b/include/llvm/InlineAsm.h
@@ -16,8 +16,8 @@
 #ifndef LLVM_INLINEASM_H
 #define LLVM_INLINEASM_H
 
+#include "llvm/ADT/SmallVector.h"
 #include "llvm/Value.h"
-#include <vector>
 
 namespace llvm {
 
@@ -87,6 +87,8 @@ public:
     isClobber           // '~x'
   };
   
+  typedef SmallVector<std::string,8> ConstraintCodeVector;
+  
   struct SubConstraintInfo {
     /// 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
@@ -95,10 +97,14 @@ public:
     signed char MatchingInput;
     /// Code - The constraint code, either the register name (in braces) or the
     /// constraint letter/number.
-    std::vector<std::string> Codes;
+    ConstraintCodeVector Codes;
     /// Default constructor.
     SubConstraintInfo() : MatchingInput(-1) {}
   };
+
+  typedef SmallVector<SubConstraintInfo,4> SubConstraintInfoVector;
+  struct ConstraintInfo;
+  typedef SmallVector<ConstraintInfo,16> ConstraintInfoVector;
   
   struct ConstraintInfo {
     /// Type - The basic type of the constraint: input/output/clobber
@@ -131,14 +137,14 @@ public:
     
     /// Code - The constraint code, either the register name (in braces) or the
     /// constraint letter/number.
-    std::vector<std::string> Codes;
+    ConstraintCodeVector Codes;
     
     /// isMultipleAlternative - '|': has multiple-alternative constraints.
     bool isMultipleAlternative;
     
     /// multipleAlternatives - If there are multiple alternative constraints,
     /// this array will contain them.  Otherwise it will be empty.
-    std::vector<SubConstraintInfo> multipleAlternatives;
+    SubConstraintInfoVector multipleAlternatives;
     
     /// The currently selected alternative constraint index.
     unsigned currentAlternativeIndex;
@@ -152,8 +158,7 @@ public:
     /// Parse - Analyze the specified string (e.g. "=*&{eax}") and fill in the
     /// fields in this structure.  If the constraint string is not understood,
     /// return true, otherwise return false.
-    bool Parse(StringRef Str, 
-               std::vector<InlineAsm::ConstraintInfo> &ConstraintsSoFar);
+    bool Parse(StringRef Str, ConstraintInfoVector &ConstraintsSoFar);
                
     /// selectAlternative - Point this constraint to the alternative constraint
     /// indicated by the index.
@@ -163,13 +168,11 @@ public:
   /// ParseConstraints - Split up the constraint string into the specific
   /// constraints and their prefixes.  If this returns an empty vector, and if
   /// the constraint string itself isn't empty, there was an error parsing.
-  static std::vector<ConstraintInfo> 
-    ParseConstraints(StringRef ConstraintString);
+  static ConstraintInfoVector ParseConstraints(StringRef ConstraintString);
   
   /// ParseConstraints - Parse the constraints of this inlineasm object, 
   /// returning them the same way that ParseConstraints(str) does.
-  std::vector<ConstraintInfo> 
-  ParseConstraints() const {
+  ConstraintInfoVector ParseConstraints() const {
     return ParseConstraints(Constraints);
   }
   
diff --git a/include/llvm/Target/TargetLowering.h b/include/llvm/Target/TargetLowering.h
index 7849752..d9b0131 100644
--- a/include/llvm/Target/TargetLowering.h
+++ b/include/llvm/Target/TargetLowering.h
@@ -1320,6 +1320,22 @@ public:
     C_Unknown              // Unsupported constraint.
   };
 
+  enum ConstraintWeight {
+    // Generic weights.
+    CW_Invalid  = -1,     // No match.
+    CW_Okay     = 0,      // Acceptable.
+    CW_Good     = 1,      // Good weight.
+    CW_Better   = 2,      // Better weight.
+    CW_Best     = 3,      // Best weight.
+    
+    // Well-known weights.
+    CW_SpecificReg  = CW_Okay,    // Specific register operands.
+    CW_Register     = CW_Good,    // Register operands.
+    CW_Memory       = CW_Better,  // Memory operands.
+    CW_Constant     = CW_Best,    // Constant operand.
+    CW_Default      = CW_Okay     // Default or don't know type.
+  };
+
   /// AsmOperandInfo - This contains information for each constraint that we are
   /// lowering.
   struct AsmOperandInfo : public InlineAsm::ConstraintInfo {
@@ -1365,24 +1381,23 @@ public:
     }
   };
   
+  typedef SmallVector<AsmOperandInfo,16> AsmOperandInfoVector;
+  
   /// ParseConstraints - Split up the constraint string from the inline
   /// assembly value into the specific constraints and their prefixes,
   /// and also tie in the associated operand values.
   /// If this returns an empty vector, and if the constraint string itself
   /// isn't empty, there was an error parsing.
-  virtual std::vector<AsmOperandInfo> ParseConstraints(
-    ImmutableCallSite CS) const;
+  virtual AsmOperandInfoVector ParseConstraints(ImmutableCallSite CS) const;
   
-  /// Examine constraint type and operand type and determine a weight value,
-  /// where: -1 = invalid match, and 0 = so-so match to 5 = good match.
+  /// Examine constraint type and operand type and determine a weight value.
   /// The operand object must already have been set up with the operand type.
-  virtual int getMultipleConstraintMatchWeight(
+  virtual ConstraintWeight getMultipleConstraintMatchWeight(
       AsmOperandInfo &info, int maIndex) const;
   
-  /// Examine constraint string and operand type and determine a weight value,
-  /// where: -1 = invalid match, and 0 = so-so match to 3 = good match.
+  /// Examine constraint string and operand type and determine a weight value.
   /// The operand object must already have been set up with the operand type.
-  virtual int getSingleConstraintMatchWeight(
+  virtual ConstraintWeight getSingleConstraintMatchWeight(
       AsmOperandInfo &info, const char *constraint) const;
 
   /// ComputeConstraintToUse - Determines the constraint code and constraint