Summary: [Lexer] Fix invalid suffix diagnostic for fixed-point literals

[nagart]

fixing lint issues

[leonardchan]

LGTM. Thanks for fixing this!

[nagart]

I don't have commit access. Could any one please help to commit this patch.
Thanks in advance.

[leonardchan]

In D80412#2056353, @nagart wrote:

I don't have commit access. Could any one please help to commit this patch.
Thanks in advance.

No problem. Committed in ef37444058550b0f49441b994c9e9368d8e42da8.

[nagart]

@leonardchan Thank you :)

clang/include/clang/Basic/DiagnosticLexKinds.td

 // Literal
 def ext_nonstandard_escape : Extension<
   "use of non-standard escape character '\\%0'">;
 def ext_unknown_escape : ExtWarn<"unknown escape sequence '\\%0'">,
   InGroup<DiagGroup<"unknown-escape-sequence">>;
 def err_invalid_digit : Error<
   "invalid digit '%0' in %select{decimal|octal|binary}1 constant">;
 def err_invalid_suffix_constant : Error<
-  "invalid suffix '%0' on %select{integer|floating}1 constant">;
+  "invalid suffix '%0' on %select{integer|floating|fixed-point}1 constant">;
 def warn_cxx11_compat_digit_separator : Warning<
   "digit separators are incompatible with C++ standards before C++14">,
   InGroup<CXXPre14Compat>, DefaultIgnore;
 def err_digit_separator_not_between_digits : Error<
   "digit separator cannot appear at %select{start|end}0 of digit sequence">;
 def warn_extraneous_char_constant : Warning<
   "extraneous characters in character constant ignored">;
 def warn_char_constant_too_large : Warning<

clang/include/clang/Lex/LiteralSupport.h

public:
   bool isImaginary : 1;     // 1.0i
   bool isFloat16 : 1;       // 1.0f16
   bool isFloat128 : 1;      // 1.0q
   uint8_t MicrosoftInteger; // Microsoft suffix extension i8, i16, i32, or i64.
 
   bool isFract : 1;         // 1.0hr/r/lr/uhr/ur/ulr
   bool isAccum : 1;         // 1.0hk/k/lk/uhk/uk/ulk
 
-  bool isFixedPointLiteral() const { return saw_fixed_point_suffix; }
+  bool isFixedPointLiteral() const {
+    return (saw_period || saw_exponent) && saw_fixed_point_suffix;
+  }
 
   bool isIntegerLiteral() const {
     return !saw_period && !saw_exponent && !isFixedPointLiteral();
   }
   bool isFloatingLiteral() const {
     return (saw_period || saw_exponent) && !isFixedPointLiteral();
   }
 

clang/lib/Lex/LiteralSupport.cpp

for (const char *c = s; c != ThisTokEnd; ++c) {
         saw_fixed_point_suffix = true;
         break;
       }
     }
   }
 
   // Parse the suffix.  At this point we can classify whether we have an FP or
   // integer constant.
+  bool isFixedPointConstant = isFixedPointLiteral();
   bool isFPConstant = isFloatingLiteral();
 
   // Loop over all of the characters of the suffix.  If we see something bad,
   // we break out of the loop.
   for (; s != ThisTokEnd; ++s) {
     switch (*s) {
     case 'R':
     case 'r':
if (isValidUDSuffix(PP.getLangOpts(), UDSuffixBuf)) {
       saw_ud_suffix = true;
       return;
     }
 
     if (s != ThisTokEnd) {
       // Report an error if there are any.
       PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, SuffixBegin - ThisTokBegin),
               diag::err_invalid_suffix_constant)
-          << StringRef(SuffixBegin, ThisTokEnd - SuffixBegin) << isFPConstant;
+          << StringRef(SuffixBegin, ThisTokEnd - SuffixBegin)
+          << (isFixedPointConstant ? 2 : isFPConstant);
       hadError = true;
     }
   }
 
   if (!hadError && saw_fixed_point_suffix) {
     assert(isFract || isAccum);
   }
 }

clang/test/Frontend/fixed_point_errors.c

 _Sat shortfract_t td_sat_short_fract;       // expected-error{{'_Sat' specifier is only valid on '_Fract' or '_Accum', not 'type-name'}}
 _Sat shortaccum_t td_sat_short_accum;       // expected-error{{'_Sat' specifier is only valid on '_Fract' or '_Accum', not 'type-name'}}
 _Sat fract_t td_sat_fract;                  // expected-error{{'_Sat' specifier is only valid on '_Fract' or '_Accum', not 'type-name'}}
 _Sat accum_t td_sat_accum;                  // expected-error{{'_Sat' specifier is only valid on '_Fract' or '_Accum', not 'type-name'}}
 _Sat longfract_t td_sat_long_fract;         // expected-error{{'_Sat' specifier is only valid on '_Fract' or '_Accum', not 'type-name'}}
 _Sat longaccum_t td_sat_long_accum;         // expected-error{{'_Sat' specifier is only valid on '_Fract' or '_Accum', not 'type-name'}}
 
 /* Bad suffixes  */
-_Accum fk = 1.0fk;    // expected-error{{invalid suffix 'fk' on integer constant}}
-_Accum kk = 1.0kk;    // expected-error{{invalid suffix 'kk' on integer constant}}
-_Accum rk = 1.0rk;    // expected-error{{invalid suffix 'rk' on integer constant}}
-_Accum rk = 1.0rr;    // expected-error{{invalid suffix 'rr' on integer constant}}
-_Accum qk = 1.0qr;    // expected-error{{invalid suffix 'qr' on integer constant}}
+_Accum fk = 1.0fk; // expected-error{{invalid suffix 'fk' on fixed-point constant}}
+_Accum kk = 1.0kk; // expected-error{{invalid suffix 'kk' on fixed-point constant}}
+_Accum rk = 1.0rk; // expected-error{{invalid suffix 'rk' on fixed-point constant}}
+_Accum rk = 1.0rr; // expected-error{{invalid suffix 'rr' on fixed-point constant}}
+_Accum qk = 1.0qr; // expected-error{{invalid suffix 'qr' on fixed-point constant}}
 
 /* Using wrong exponent notation */
-_Accum dec_with_hex_exp1 = 0.1p10k;    // expected-error{{invalid suffix 'p10k' on integer constant}}
-_Accum dec_with_hex_exp2 = 0.1P10k;    // expected-error{{invalid suffix 'P10k' on integer constant}}
+_Accum dec_with_hex_exp1 = 0.1p10k;    // expected-error{{invalid suffix 'p10k' on fixed-point constant}}
+_Accum dec_with_hex_exp2 = 0.1P10k;    // expected-error{{invalid suffix 'P10k' on fixed-point constant}}
 _Accum hex_with_dex_exp1 = 0x0.1e10k;  // expected-error{{hexadecimal floating constant requires an exponent}}
 _Accum hex_with_dex_exp2 = 0x0.1E10k;  // expected-error{{hexadecimal floating constant requires an exponent}}
 
 void CheckSuffixOnIntegerLiterals() {
   _Accum short_acc_int;
   _Accum acc_int;
   _Accum long_acc_int;