authorgravatar for thatlemon@gmail.comLemonBoy <thatlemon@gmail.com> 2021-04-24 18:42:23+02:00
committergravatar for thatlemon@gmail.comLemonBoy <thatlemon@gmail.com> 2021-04-24 18:42:23+02:00
log7c3896e6cd20a51e63a018fd2e05ea3c552b7401
tree00900f2c69d30bec5965610d19966a1e17214980
parent4ec6d174adc038741f1274d157f5253752eb8d51

translate-c: Prevent mistranslation of fp literals

When trying to retrieve 80bit fp values from clang using getValueAsApproximateDouble we'd eventually hit the ceiling value and return infinity, an invalid value for a fp literal. Add some logic to prevent this error and warn the user. Closes #8602

4 files changed, 47 insertions(+), 2 deletions(-)

src/clang.zig+16
......@@ -104,6 +104,16 @@ pub const APFloat = opaque {
104104 extern fn ZigClangAPFloat_toString(*const APFloat, precision: c_uint, maxPadding: c_uint, truncateZero: bool) [*:0]const u8;
105105};
106106
107pub const APFloatBaseSemantics = extern enum {
108 IEEEhalf,
109 BFloat,
110 IEEEsingle,
111 IEEEdouble,
112 x86DoubleExtended,
113 IEEEquad,
114 PPCDoubleDouble,
115};
116
107117pub const APInt = opaque {
108118 pub const getLimitedValue = ZigClangAPInt_getLimitedValue;
109119 extern fn ZigClangAPInt_getLimitedValue(*const APInt, limit: u64) u64;
......@@ -455,6 +465,12 @@ pub const FileID = opaque {};
455465pub const FloatingLiteral = opaque {
456466 pub const getValueAsApproximateDouble = ZigClangFloatingLiteral_getValueAsApproximateDouble;
457467 extern fn ZigClangFloatingLiteral_getValueAsApproximateDouble(*const FloatingLiteral) f64;
468
469 pub const getBeginLoc = ZigClangIntegerLiteral_getBeginLoc;
470 extern fn ZigClangIntegerLiteral_getBeginLoc(*const FloatingLiteral) SourceLocation;
471
472 pub const getRawSemantics = ZigClangFloatingLiteral_getRawSemantics;
473 extern fn ZigClangFloatingLiteral_getRawSemantics(*const FloatingLiteral) APFloatBaseSemantics;
458474};
459475
460476pub const ForStmt = opaque {
src/translate_c.zig+15-2
......@@ -3547,9 +3547,22 @@ fn transCPtrCast(
35473547 }
35483548}
35493549
3550fn transFloatingLiteral(c: *Context, scope: *Scope, stmt: *const clang.FloatingLiteral, used: ResultUsed) TransError!Node {
3550fn transFloatingLiteral(c: *Context, scope: *Scope, expr: *const clang.FloatingLiteral, used: ResultUsed) TransError!Node {
3551 switch (expr.getRawSemantics()) {
3552 .IEEEhalf, // f16
3553 .IEEEsingle, // f32
3554 .IEEEdouble, // f64
3555 => {},
3556 else => |format| return fail(
3557 c,
3558 error.UnsupportedTranslation,
3559 expr.getBeginLoc(),
3560 "unsupported floating point constant format {}",
3561 .{format},
3562 ),
3563 }
35513564 // TODO use something more accurate
3552 var dbl = stmt.getValueAsApproximateDouble();
3565 var dbl = expr.getValueAsApproximateDouble();
35533566 const is_negative = dbl < 0;
35543567 if (is_negative) dbl = -dbl;
35553568 const str = if (dbl == std.math.floor(dbl))
src/zig_clang.cpp+5
......@@ -2528,6 +2528,11 @@ double ZigClangFloatingLiteral_getValueAsApproximateDouble(const ZigClangFloatin
25282528 return casted->getValueAsApproximateDouble();
25292529}
25302530
2531ZigClangAPFloatBase_Semantics ZigClangFloatingLiteral_getRawSemantics(const ZigClangFloatingLiteral *self) {
2532 auto casted = reinterpret_cast<const clang::FloatingLiteral *>(self);
2533 return static_cast<ZigClangAPFloatBase_Semantics>(casted->getRawSemantics());
2534}
2535
25312536enum ZigClangStringLiteral_StringKind ZigClangStringLiteral_getKind(const struct ZigClangStringLiteral *self) {
25322537 auto casted = reinterpret_cast<const clang::StringLiteral *>(self);
25332538 return (ZigClangStringLiteral_StringKind)casted->getKind();
src/zig_clang.h+11
......@@ -881,6 +881,16 @@ enum ZigClangAPFloat_roundingMode {
881881 ZigClangAPFloat_roundingMode_Invalid = -1,
882882};
883883
884enum ZigClangAPFloatBase_Semantics {
885 ZigClangAPFloatBase_Semantics_IEEEhalf,
886 ZigClangAPFloatBase_Semantics_BFloat,
887 ZigClangAPFloatBase_Semantics_IEEEsingle,
888 ZigClangAPFloatBase_Semantics_IEEEdouble,
889 ZigClangAPFloatBase_Semantics_x87DoubleExtended,
890 ZigClangAPFloatBase_Semantics_IEEEquad,
891 ZigClangAPFloatBase_Semantics_PPCDoubleDouble,
892};
893
884894enum ZigClangStringLiteral_StringKind {
885895 ZigClangStringLiteral_StringKind_Ascii,
886896 ZigClangStringLiteral_StringKind_Wide,
......@@ -1142,6 +1152,7 @@ ZIG_EXTERN_C struct ZigClangSourceLocation ZigClangDeclStmt_getBeginLoc(const st
11421152ZIG_EXTERN_C unsigned ZigClangAPFloat_convertToHexString(const struct ZigClangAPFloat *self, char *DST,
11431153 unsigned HexDigits, bool UpperCase, enum ZigClangAPFloat_roundingMode RM);
11441154ZIG_EXTERN_C double ZigClangFloatingLiteral_getValueAsApproximateDouble(const ZigClangFloatingLiteral *self);
1155ZIG_EXTERN_C ZigClangAPFloatBase_Semantics ZigClangFloatingLiteral_getRawSemantics(const ZigClangFloatingLiteral *self);
11451156
11461157ZIG_EXTERN_C enum ZigClangStringLiteral_StringKind ZigClangStringLiteral_getKind(const struct ZigClangStringLiteral *self);
11471158ZIG_EXTERN_C uint32_t ZigClangStringLiteral_getCodeUnit(const struct ZigClangStringLiteral *self, size_t i);