[Flang][Docs] Clean up flang/docs/IntrinsicTypes.md documentation #162184
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Light cleanup of the IntrinsicTypes.md documentation.
mcinally
requested review from
sscalpone,
tarunprabhu,
jeanPerier,
klausler,
vdonaldson and
vzakhari
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Screenshots for readability... 
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| DOUBLE PRECISION 8 | ||
| LOGICAL 4 | ||
| Modules compiled with different `-fdefault-real-<kind>` and | ||
| `-f-default-integer-<kind>` may be freely mixed. Module files encode the kind |
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I am not sure that this is good message to send, in general. Mixing files compiled with different default kinds may cause problems for calls to subprograms without explicit interfaces.
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Thanks @mcinally. I particularly appreciated the screenshots - they made things much easier.
| which determines the representation method for the specified type. | ||
| The intrinsic type character also has a length type parameter called LEN, | ||
| The intrinsic type character also has a length type parameter called `LEN`, |
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"length parameter" seems clearer to me than "length type parameter", but the same comment applies here as for "kind type parameter".
| The intrinsic type character also has a length type parameter called `LEN`, | |
| The intrinsic type `CHARACTER` also has a length parameter called `LEN`, |
| Intrinsic types are integer, real, complex, character, and logical. | ||
| All intrinsic types have a kind type parameter called KIND, | ||
| Intrinsic types are `INTEGER`, `REAL`, `COMPLEX`, `CHARACTER`, and `LOGICAL`. | ||
| All intrinsic types have a kind type parameter called `KIND`, |
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Do you know if the term "kind type parameter" is in common use/the language used in the standard? Just "kind parameter" seems clearer to me. But if the former is the convention (or in the official standard), we should prefer that.
| All intrinsic types have a kind type parameter called `KIND`, | |
| All intrinsic types have a kind parameter called `KIND` |
| which determines the length of the character string. | ||
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| The implementation of `CHARACTER` type in f18 is described | ||
| The implementation of the `CHARACTER` type in f18 is described |
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It may be a good idea to switch to using flang instead of f18. The latter is the historic name of this compiler/project, but since the the official binary is also called "flang", so we probably should be consistent.
If you don't mind this being held up a little, I can bring it up at the flang call tomorrow (Wednesday, 8 Oct), to see if the community has any objections. Does that sound reasonable?
| The implementation of the `CHARACTER` type in f18 is described | |
| The implementation of the `CHARACTER` type in `flang` is described |
| LOGICAL(KIND=2) 16-bit integer | ||
| LOGICAL(KIND=4) 32-bit integer | ||
| LOGICAL(KIND=8) 64-bit integer | ||
| ### Defaults kinds |
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| ### Defaults kinds | |
| ### Default kinds |
| * `INTEGER` 4 | ||
| * `REAL` 4 | ||
| * `COMPLEX` 4 | ||
| * `DOUBLE PRECISION` 8 |
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DOUBLE PRECISION is not in the table above. Is this intentional?
| quad precision type is supported. | ||
| * No 128-bit logical support. |
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| * No 128-bit logical support. | |
| * 128-bit `LOGICAL` is not supported |
| #### Modifying the default kind with default-integer-8: | ||
| INTEGER 8 | ||
| LOGICAL 8 | ||
| * `REAL` 8 |
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Consider adding a sentence before these bullet points clarifying that the use of -fdefault-real-8 will only affect the default kinds for the following types.
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| ## Representation of LOGICAL variables | ||
| * `INTEGER` 8 |
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Consider adding a sentence before these bullet points clarifying that the use of -fdefault-integer-8 will only affect the default kinds for the following types.
| share the following characteristics: | ||
| .TRUE. is represented as 1_kind | ||
| .FALSE. is represented as 0_kind | ||
| The Fortran standard specifies that a logical has two values, `.TRUE.` and |
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| The Fortran standard specifies that a logical has two values, `.TRUE.` and | |
| The Fortran standard specifies that a `LOGICAL` has two values, `.TRUE.` and |
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| Tests for true is *integer value is not zero*. | ||
| Flang specifies that logical literal constants with `KIND=[1|2|4|8]` share the |
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| Flang specifies that logical literal constants with `KIND=[1|2|4|8]` share the | |
| Flang specifies that `LOGICAL` literal constants with `KIND=[1|2|4|8]` share the |
Light cleanup of the IntrinsicTypes.md documentation:
LOGICALimplementation.TYPESandKINDS.-fdefault-[real|integer]-<kind>.