reimplement the regex matching strategy by building a single

regex and matching it instead of trying to match chunks at a time.
Matching chunks at a time broke with check lines like 
  CHECK: foo {{.*}}bar
because the .* would eat the entire rest of the line and bar would
never match.

Now we just escape the fixed strings for the user, so that something
like:
  CHECK: a() {{.*}}???
is matched as:
  CHECK: {{a\(\) .*\?\?\?}}
transparently "under the covers".



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82779 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2009-09-25 17:23:43 +00:00
parent 52fb79b7f9
commit 5d6a05f4d4
2 changed files with 59 additions and 96 deletions

View File

@ -59,10 +59,10 @@ bb12:
; X64: test4:
; X64: notl %eax
; X64: andl {{.*%eax}}
; X64: andl {{.*}}%eax
; X32: test4:
; X32: notl %edx
; X32: andl {{.*%edx}}
; X32: andl {{.*}}%edx
}
define i16 @test5(i16 %a, i16 %b) nounwind {
@ -81,10 +81,10 @@ bb12:
ret i16 %tmp3
; X64: test5:
; X64: notw %ax
; X64: andw {{.*%ax}}
; X64: andw {{.*}}%ax
; X32: test5:
; X32: notw %dx
; X32: andw {{.*%dx}}
; X32: andw {{.*}}%dx
}
define i8 @test6(i8 %a, i8 %b) nounwind {
@ -103,10 +103,10 @@ bb12:
ret i8 %tmp3
; X64: test6:
; X64: notb %al
; X64: andb {{.*%al}}
; X64: andb {{.*}}%al
; X32: test6:
; X32: notb %dl
; X32: andb {{.*%dl}}
; X32: andb {{.*}}%dl
}
define i32 @test7(i32 %a, i32 %b) nounwind {
@ -125,9 +125,9 @@ bb12:
ret i32 %tmp3
; X64: test7:
; X64: xorl $2147483646, %eax
; X64: andl {{.*%eax}}
; X64: andl {{.*}}%eax
; X32: test7:
; X32: xorl $2147483646, %edx
; X32: andl {{.*%edx}}
; X32: andl {{.*}}%edx
}

View File

@ -44,39 +44,13 @@ NoCanonicalizeWhiteSpace("strict-whitespace",
// Pattern Handling Code.
//===----------------------------------------------------------------------===//
class PatternChunk {
StringRef Str;
bool isRegEx;
public:
PatternChunk(StringRef S, bool isRE) : Str(S), isRegEx(isRE) {}
size_t Match(StringRef Buffer, size_t &MatchLen) const {
if (!isRegEx) {
// Fixed string match.
MatchLen = Str.size();
return Buffer.find(Str);
}
// Regex match.
SmallVector<StringRef, 4> MatchInfo;
if (!Regex(Str, Regex::Sub|Regex::Newline).match(Buffer, &MatchInfo))
return StringRef::npos;
// Successful regex match.
assert(!MatchInfo.empty() && "Didn't get any match");
StringRef FullMatch = MatchInfo[0];
MatchLen = FullMatch.size();
return FullMatch.data()-Buffer.data();
}
};
class Pattern {
/// Chunks - The pattern chunks to match. If the bool is false, it is a fixed
/// string match, if it is true, it is a regex match.
SmallVector<PatternChunk, 4> Chunks;
/// FixedStr - If non-empty, this pattern is a fixed string match with the
/// specified fixed string.
StringRef FixedStr;
/// RegEx - If non-empty, this is a regex pattern.
std::string RegExStr;
public:
Pattern() { }
@ -87,6 +61,9 @@ public:
/// returns the position that is matched or npos if there is no match. If
/// there is a match, the size of the matched string is returned in MatchLen.
size_t Match(StringRef Buffer, size_t &MatchLen) const;
private:
void AddFixedStringToRegEx(StringRef FixedStr);
};
bool Pattern::ParsePattern(StringRef PatternStr, SourceMgr &SM) {
@ -109,17 +86,15 @@ bool Pattern::ParsePattern(StringRef PatternStr, SourceMgr &SM) {
return false;
}
// Otherwise, there is at least one regex piece.
// Scan the pattern to break it into regex and non-regex pieces.
// Otherwise, there is at least one regex piece. Build up the regex pattern
// by escaping scary characters in fixed strings, building up one big regex.
while (!PatternStr.empty()) {
// Handle fixed string matches.
if (PatternStr.size() < 2 ||
PatternStr[0] != '{' || PatternStr[1] != '{') {
// Find the end, which is the start of the next regex.
size_t FixedMatchEnd = PatternStr.find("{{");
Chunks.push_back(PatternChunk(PatternStr.substr(0, FixedMatchEnd),false));
AddFixedStringToRegEx(PatternStr.substr(0, FixedMatchEnd));
PatternStr = PatternStr.substr(FixedMatchEnd);
continue;
}
@ -132,7 +107,8 @@ bool Pattern::ParsePattern(StringRef PatternStr, SourceMgr &SM) {
return true;
}
Regex R(PatternStr.substr(2, End-2));
StringRef RegexStr = PatternStr.substr(2, End-2);
Regex R(RegexStr);
std::string Error;
if (!R.isValid(Error)) {
SM.PrintMessage(SMLoc::getFromPointer(PatternStr.data()+2),
@ -140,13 +116,41 @@ bool Pattern::ParsePattern(StringRef PatternStr, SourceMgr &SM) {
return true;
}
Chunks.push_back(PatternChunk(PatternStr.substr(2, End-2), true));
RegExStr += RegexStr.str();
PatternStr = PatternStr.substr(End+2);
}
return false;
}
void Pattern::AddFixedStringToRegEx(StringRef FixedStr) {
// Add the characters from FixedStr to the regex, escaping as needed. This
// avoids "leaning toothpicks" in common patterns.
for (unsigned i = 0, e = FixedStr.size(); i != e; ++i) {
switch (FixedStr[i]) {
// These are the special characters matched in "p_ere_exp".
case '(':
case ')':
case '^':
case '$':
case '|':
case '*':
case '+':
case '?':
case '.':
case '[':
case '\\':
case '{':
RegExStr += '\\';
// FALL THROUGH.
default:
RegExStr += FixedStr[i];
break;
}
}
}
/// Match - Match the pattern string against the input buffer Buffer. This
/// returns the position that is matched or npos if there is no match. If
/// there is a match, the size of the matched string is returned in MatchLen.
@ -157,58 +161,17 @@ size_t Pattern::Match(StringRef Buffer, size_t &MatchLen) const {
return Buffer.find(FixedStr);
}
size_t FirstMatch = StringRef::npos;
MatchLen = 0;
// Regex match.
SmallVector<StringRef, 4> MatchInfo;
if (!Regex(RegExStr, Regex::Sub|Regex::Newline).match(Buffer, &MatchInfo))
return StringRef::npos;
while (!Buffer.empty()) {
StringRef MatchAttempt = Buffer;
unsigned ChunkNo = 0, e = Chunks.size();
for (; ChunkNo != e; ++ChunkNo) {
size_t ThisMatch, ThisLength = StringRef::npos;
ThisMatch = Chunks[ChunkNo].Match(MatchAttempt, ThisLength);
// Otherwise, what we do depends on if this is the first match or not. If
// this is the first match, it doesn't match to match at the start of
// MatchAttempt.
if (ChunkNo == 0) {
// If the first match fails then this pattern will never match in
// Buffer.
if (ThisMatch == StringRef::npos)
return ThisMatch;
FirstMatch = ThisMatch;
MatchAttempt = MatchAttempt.substr(FirstMatch);
ThisMatch = 0;
}
// If this chunk didn't match, then the entire pattern didn't match from
// FirstMatch, try later in the buffer.
if (ThisMatch == StringRef::npos)
break;
// Ok, if the match didn't match at the beginning of MatchAttempt, then we
// have something like "ABC{{DEF}} and something was in-between. Reject
// the match.
if (ThisMatch != 0)
break;
// Otherwise, match the string and move to the next chunk.
MatchLen += ThisLength;
MatchAttempt = MatchAttempt.substr(ThisLength);
}
// If the whole thing matched, we win.
if (ChunkNo == e)
return FirstMatch;
// Otherwise, try matching again after FirstMatch to see if this pattern
// matches later in the buffer.
Buffer = Buffer.substr(FirstMatch+1);
}
// Successful regex match.
assert(!MatchInfo.empty() && "Didn't get any match");
StringRef FullMatch = MatchInfo[0];
// If we ran out of stuff to scan, then we didn't match.
return StringRef::npos;
MatchLen = FullMatch.size();
return FullMatch.data()-Buffer.data();
}