[mlir][affineexpr] Changing AsmParser::parseAffineExpr API to use ArrayRef

The methods added by D154177 don't require the `symbolSet` parameter to be mutable nor to have the `SmallVectorImpl` type, so this commit changes them to accept `ArrayRef` instead: both for generality, and to make the non-mutation an explicit part of the API.

Reviewed By: aartbik, Peiming

Differential Revision: https://reviews.llvm.org/D154751

Author: wrengr

mlir/include/mlir/IR/OpImplementation.h

@@ -1035,7 +1035,7 @@ class AsmParser {
   /// Parse an affine expr instance into 'expr' using the already computed
   /// mapping from symbols to affine expressions in 'symbolSet'.
   virtual ParseResult
-  parseAffineExpr(SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
+  parseAffineExpr(ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
                   AffineExpr &expr) = 0;
 
   /// Parse an integer set instance into 'set'.

mlir/lib/AsmParser/AffineParser.cpp

@@ -53,9 +53,9 @@ class AffineParser : public Parser {
   ParseResult parseAffineMapRange(unsigned numDims, unsigned numSymbols,
                                   AffineMap &result);
   ParseResult parseAffineMapOrIntegerSetInline(AffineMap &map, IntegerSet &set);
-  ParseResult parseAffineExprInline(
-      SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
-      AffineExpr &expr);
+  ParseResult
+  parseAffineExprInline(ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
+                        AffineExpr &expr);
   ParseResult parseIntegerSetConstraints(unsigned numDims, unsigned numSymbols,
                                          IntegerSet &result);
   ParseResult parseAffineMapOfSSAIds(AffineMap &map,
@@ -538,9 +538,8 @@ ParseResult AffineParser::parseAffineMapOrIntegerSetInline(AffineMap &map,
 
 /// Parse an affine expresion definition inline, with given symbols.
 ParseResult AffineParser::parseAffineExprInline(
-    SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
-    AffineExpr &expr) {
-  dimsAndSymbols.assign(symbolSet);
+    ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet, AffineExpr &expr) {
+  dimsAndSymbols.assign(symbolSet.begin(), symbolSet.end());
   expr = parseAffineExpr();
   return success(expr != nullptr);
 }
@@ -716,8 +715,7 @@ ParseResult Parser::parseAffineMapReference(AffineMap &map) {
   return success();
 }
 ParseResult Parser::parseAffineExprReference(
-    SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
-    AffineExpr &expr) {
+    ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet, AffineExpr &expr) {
   return AffineParser(state).parseAffineExprInline(symbolSet, expr);
 }
 ParseResult Parser::parseIntegerSetReference(IntegerSet &set) {

mlir/lib/AsmParser/AsmParserImpl.h

@@ -459,7 +459,7 @@ class AsmParserImpl : public BaseT {
   /// Parse an affine expr instance into 'expr' using the already computed
   /// mapping from symbols to affine expressions in 'symbolSet'.
   ParseResult
-  parseAffineExpr(SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
+  parseAffineExpr(ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
                   AffineExpr &expr) override {
     return parser.parseAffineExprReference(symbolSet, expr);
   }

mlir/lib/AsmParser/Parser.h

@@ -300,9 +300,9 @@ class Parser {
   ParseResult parseAffineMapOrIntegerSetReference(AffineMap &map,
                                                   IntegerSet &set);
   ParseResult parseAffineMapReference(AffineMap &map);
-  ParseResult parseAffineExprReference(
-      SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
-      AffineExpr &expr);
+  ParseResult
+  parseAffineExprReference(ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
+                           AffineExpr &expr);
   ParseResult parseIntegerSetReference(IntegerSet &set);
 
   /// Parse an AffineMap where the dim and symbol identifiers are SSA ids.