[FileCheck] Allow parenthesized expressions

With this change it is be possible to write FileCheck expressions such
as [[#(VAR+1)-2]]. Currently, the only supported arithmetic operators are
plus and minus, so this is not particularly useful yet. However, it our
CHERI fork we have tests that benefit from having multiplication in
FileCheck expressions. Allowing parenthesized expressions is the simplest
way for us to work around the current lack of operator precedence in
FileCheck expressions.

Reviewed By: thopre, jhenderson
Differential Revision: https://reviews.llvm.org/D77383

diff --git a/llvm/docs/CommandGuide/FileCheck.rst b/llvm/docs/CommandGuide/FileCheck.rst
index 7d9a69e..d8a2e34 100644 (file)
--- a/llvm/docs/CommandGuide/FileCheck.rst
+++ b/llvm/docs/CommandGuide/FileCheck.rst
@@ -694,6 +694,8 @@ The syntax of a numeric substitution is ``[[#%<fmtspec>,<expr>]]`` where:
   A numeric operand is a previously defined numeric variable, or an integer
   literal. The supported operators are ``+`` and ``-``. Spaces are accepted
   before, after and between any of these elements.
+  There is currently no support for operator precendence, but parentheses can
+  be used to change the evaluation order.
 
 For example:
 

diff --git a/llvm/lib/Support/FileCheck.cpp b/llvm/lib/Support/FileCheck.cpp
index 2797b82..300eea8 100644 (file)
--- a/llvm/lib/Support/FileCheck.cpp
+++ b/llvm/lib/Support/FileCheck.cpp
@@ -273,6 +273,13 @@ Expected<std::unique_ptr<NumericVariableUse>> Pattern::parseNumericVariableUse(
 Expected<std::unique_ptr<ExpressionAST>> Pattern::parseNumericOperand(
     StringRef &Expr, AllowedOperand AO, Optional<size_t> LineNumber,
     FileCheckPatternContext *Context, const SourceMgr &SM) {
+  if (Expr.startswith("(")) {
+    if (AO != AllowedOperand::Any)
+      return ErrorDiagnostic::get(
+          SM, Expr, "parenthesized expression not permitted here");
+    return parseParenExpr(Expr, LineNumber, Context, SM);
+  }
+
   if (AO == AllowedOperand::LineVar || AO == AllowedOperand::Any) {
     // Try to parse as a numeric variable use.
     Expected<Pattern::VariableProperties> ParseVarResult =
@@ -300,6 +307,38 @@ Expected<std::unique_ptr<ExpressionAST>> Pattern::parseNumericOperand(
                               "invalid operand format '" + Expr + "'");
 }
 
+Expected<std::unique_ptr<ExpressionAST>>
+Pattern::parseParenExpr(StringRef &Expr, Optional<size_t> LineNumber,
+                        FileCheckPatternContext *Context, const SourceMgr &SM) {
+  Expr = Expr.ltrim(SpaceChars);
+  assert(Expr.startswith("("));
+
+  // Parse right operand.
+  Expr.consume_front("(");
+  Expr = Expr.ltrim(SpaceChars);
+  if (Expr.empty())
+    return ErrorDiagnostic::get(SM, Expr, "missing operand in expression");
+
+  // Note: parseNumericOperand handles nested opening parentheses.
+  Expected<std::unique_ptr<ExpressionAST>> SubExprResult =
+      parseNumericOperand(Expr, AllowedOperand::Any, LineNumber, Context, SM);
+  Expr = Expr.ltrim(SpaceChars);
+  while (SubExprResult && !Expr.empty() && !Expr.startswith(")")) {
+    StringRef OrigExpr = Expr;
+    SubExprResult = parseBinop(OrigExpr, Expr, std::move(*SubExprResult), false,
+                               LineNumber, Context, SM);
+    Expr = Expr.ltrim(SpaceChars);
+  }
+  if (!SubExprResult)
+    return SubExprResult;
+
+  if (!Expr.consume_front(")")) {
+    return ErrorDiagnostic::get(SM, Expr,
+                                "missing ')' at end of nested expression");
+  }
+  return SubExprResult;
+}
+
 static uint64_t add(uint64_t LeftOp, uint64_t RightOp) {
   return LeftOp + RightOp;
 }

diff --git a/llvm/lib/Support/FileCheckImpl.h b/llvm/lib/Support/FileCheckImpl.h
index 8a7d583..f4f2fc2 100644 (file)
--- a/llvm/lib/Support/FileCheckImpl.h
+++ b/llvm/lib/Support/FileCheckImpl.h
@@ -665,7 +665,8 @@ private:
   /// \p Context points to the class instance holding the live string and
   /// numeric variables. \returns the class representing that operand in the
   /// AST of the expression or an error holding a diagnostic against \p SM
-  /// otherwise.
+  /// otherwise. If \p Expr starts with a "(" this function will attempt to
+  /// parse a parenthesized expression.
   static Expected<std::unique_ptr<ExpressionAST>>
   parseNumericOperand(StringRef &Expr, AllowedOperand AO,
                       Optional<size_t> LineNumber,
@@ -684,6 +685,16 @@ private:
              std::unique_ptr<ExpressionAST> LeftOp, bool IsLegacyLineExpr,
              Optional<size_t> LineNumber, FileCheckPatternContext *Context,
              const SourceMgr &SM);
+
+  /// Parses a parenthesized expression inside \p Expr at line \p LineNumber, or
+  /// before input is parsed if \p LineNumber is None. \p Expr must start with
+  /// a '('. Accepts both literal values and numeric variables. Parameter \p
+  /// Context points to the class instance holding the live string and numeric
+  /// variables. \returns the class representing that operand in the AST of the
+  /// expression or an error holding a diagnostic against \p SM otherwise.
+  static Expected<std::unique_ptr<ExpressionAST>>
+  parseParenExpr(StringRef &Expr, Optional<size_t> LineNumber,
+                 FileCheckPatternContext *Context, const SourceMgr &SM);
 };
 
 //===----------------------------------------------------------------------===//

diff --git a/llvm/test/FileCheck/numeric-expression.txt b/llvm/test/FileCheck/numeric-expression.txt
index 81a82b3..3d33e64 100644 (file)
--- a/llvm/test/FileCheck/numeric-expression.txt
+++ b/llvm/test/FileCheck/numeric-expression.txt
@@ -164,6 +164,20 @@ DEF EXPR GOOD MATCH  // CHECK-LABEL: DEF EXPR GOOD MATCH
 EMPTY NUM EXPR  // CHECK-LABEL: EMPTY NUM EXPR
 foo 104 bar  // CHECK-NEXT: {{^}}foo [[#]] bar
 
+; Numeric expressions using parentheses.
+RUN: %ProtectFileCheckOutput \
+RUN: not FileCheck -D#NUMVAR=10 --check-prefix PAREN-OP \
+RUN:               --input-file %s %s 2>&1 \
+RUN:   | FileCheck --strict-whitespace --check-prefix PAREN-OP-MSG %s
+
+PAREN EXPRESSIONS // PAREN-OP-LABEL: PAREN EXPRESSIONS
+11  // PAREN-OP-NEXT: [[#(NUMVAR+2)-1]]
+11  // PAREN-OP-NEXT: [[#NUMVAR+(2-1)]]
+11  // PAREN-OP-NEXT: [[#NUMVAR+(2-1]]
+PAREN-OP-MSG: numeric-expression.txt:[[#@LINE-1]]:36: error: missing ')' at end of nested expression
+PAREN-OP-MSG-NEXT: {{P}}AREN-OP-NEXT: {{\[\[#NUMVAR\+\(2\-1]\]}}
+PAREN-OP-MSG-NEXT: {{^}}                                   ^{{$}}
+
 ; Numeric expression using undefined variables.
 RUN: %ProtectFileCheckOutput \
 RUN: not FileCheck --check-prefix UNDEF-USE --input-file %s %s 2>&1 \

diff --git a/llvm/unittests/Support/FileCheckTest.cpp b/llvm/unittests/Support/FileCheckTest.cpp
index 6b0eee4..75b7fba 100644 (file)
--- a/llvm/unittests/Support/FileCheckTest.cpp
+++ b/llvm/unittests/Support/FileCheckTest.cpp
@@ -724,6 +724,46 @@ TEST_F(FileCheckTest, ParseNumericSubstitutionBlock) {
       "implicit format conflict between 'FOO' (%u) and "
       "'VAR_LOWER_HEX' (%x), need an explicit format specifier",
       Tester.parseSubst("FOO+VAR_LOWER_HEX").takeError());
+
+  // Simple parenthesized expressions:
+  EXPECT_THAT_EXPECTED(Tester.parseSubst("(1)"), Succeeded());
+  EXPECT_THAT_EXPECTED(Tester.parseSubst("(1+1)"), Succeeded());
+  EXPECT_THAT_EXPECTED(Tester.parseSubst("(1)+1"), Succeeded());
+  EXPECT_THAT_EXPECTED(Tester.parseSubst("((1)+1)"), Succeeded());
+  EXPECT_THAT_EXPECTED(Tester.parseSubst("((1)+X)"), Succeeded());
+  EXPECT_THAT_EXPECTED(Tester.parseSubst("((X)+Y)"), Succeeded());
+
+  expectDiagnosticError("missing operand in expression",
+                        Tester.parseSubst("(").takeError());
+  expectDiagnosticError("missing ')' at end of nested expression",
+                        Tester.parseSubst("(1").takeError());
+  expectDiagnosticError("missing operand in expression",
+                        Tester.parseSubst("(1+").takeError());
+  expectDiagnosticError("missing ')' at end of nested expression",
+                        Tester.parseSubst("(1+1").takeError());
+  expectDiagnosticError("missing ')' at end of nested expression",
+                        Tester.parseSubst("((1+2+3").takeError());
+  expectDiagnosticError("missing ')' at end of nested expression",
+                        Tester.parseSubst("((1+2)+3").takeError());
+
+  // Test missing operation between operands:
+  expectDiagnosticError("unsupported operation '('",
+                        Tester.parseSubst("(1)(2)").takeError());
+  expectDiagnosticError("unsupported operation '('",
+                        Tester.parseSubst("2(X)").takeError());
+
+  // Test more closing than opening parentheses. The diagnostic messages are
+  // not ideal, but for now simply check that we reject invalid input.
+  expectDiagnosticError("invalid operand format ')'",
+                        Tester.parseSubst(")").takeError());
+  expectDiagnosticError("unsupported operation ')'",
+                        Tester.parseSubst("1)").takeError());
+  expectDiagnosticError("unsupported operation ')'",
+                        Tester.parseSubst("(1+2))").takeError());
+  expectDiagnosticError("unsupported operation ')'",
+                        Tester.parseSubst("(2))").takeError());
+  expectDiagnosticError("unsupported operation ')'",
+                        Tester.parseSubst("(1))(").takeError());
 }
 
 TEST_F(FileCheckTest, ParsePattern) {
@@ -844,6 +884,52 @@ TEST_F(FileCheckTest, Match) {
                        Succeeded());
 }
 
+TEST_F(FileCheckTest, MatchParen) {
+  PatternTester Tester;
+  // Check simple parenthesized expressions
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR:]]"));
+  expectNotFoundError(Tester.match("FAIL").takeError());
+  expectNotFoundError(Tester.match("").takeError());
+  EXPECT_THAT_EXPECTED(Tester.match("18"), Succeeded());
+
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR + (2 + 2)]]"));
+  expectNotFoundError(Tester.match("21").takeError());
+  EXPECT_THAT_EXPECTED(Tester.match("22"), Succeeded());
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR + (2)]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("20"), Succeeded());
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR+(2)]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("20"), Succeeded());
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR+(NUMVAR)]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("36"), Succeeded());
+
+  // Check nested parenthesized expressions:
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR+(2+(2))]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("22"), Succeeded());
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR+(2+(NUMVAR))]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("38"), Succeeded());
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR+((((NUMVAR))))]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("36"), Succeeded());
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#NUMVAR+((((NUMVAR)))-1)-1]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("34"), Succeeded());
+
+  // Parentheses can also be the first character after the '#':
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#(NUMVAR)]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("18"), Succeeded());
+  Tester.initNextPattern();
+  ASSERT_FALSE(Tester.parsePattern("[[#(NUMVAR+2)]]"));
+  EXPECT_THAT_EXPECTED(Tester.match("20"), Succeeded());
+}
+
 TEST_F(FileCheckTest, Substitution) {
   SourceMgr SM;
   FileCheckPatternContext Context;