[WIP] Intrinsics now platform dependent. LibC::PtrdiffT type introduced. #4624
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…g two pointers. ptrdiff_t is used for pointer arithmetic and array indexing, if negative values are possible. Refs crystal-lang#823, crystal-lang#4589.
akzhan
changed the title
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Got failure on 32bit build. Will check. |
| @@ -0,0 +1,20 @@ | |||
| lib Intrinsics | |||
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Intrinsics aren't LibC bindings (i.e. calls to external symbols) but LLVM intrinsics (inlined calls); they won't be generated automatically; they aren't system dependent (but arch dependent).
I.e.: they have nothing to do under LibC, please put them back as src/intrinsics.cr or maybe src/crystal/intrinsics.cr, along with the flag macro to select either the u32 or u64 calls.
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I like idea of separated files per arch. Will try to rework it accordingly.
| @@ -242,7 +242,7 @@ struct Pointer(T) | |||
| raise ArgumentError.new("Negative count") if count < 0 | |||
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| if self.class == source.class | |||
| Intrinsics.memcpy(self.as(Void*), source.as(Void*), (count * sizeof(T)).to_u32, 0_u32, false) | |||
| Intrinsics.memcpy(self.as(Void*), source.as(Void*), Intrinsics::SizeT.new(count) * sizeof(T), 0_u32, false) | |||
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Why introduce Intrinsics::SizeT but use LibC::SizeT below? This is confusing and a duplication.
| @@ -395,7 +395,7 @@ struct Pointer(T) | |||
| # ptr.address # => 0 | |||
| # ``` | |||
| def self.null | |||
| new 0_u64 | |||
| new LibC::SizeT.new(0) | |||
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size_tis a length type (as in allocation size), you meantintptr_t(pointer size);- you must hack the compiler for this to compile on 32bit platforms (
Pointer.new(UInt64)is a Crystal intrinsic).
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Thanks, it was a big mistake.
| @@ -405,7 +405,7 @@ struct Pointer(T) | |||
| # ptr.address # => 5678 | |||
| # ``` | |||
| def self.new(address : Int) | |||
| new address.to_u64 | |||
| new LibC::SizeT.new(address) | |||
| @@ -78,7 +78,7 @@ struct Pointer(T) | |||
| # ptr2.address # => 1238 | |||
| # ``` | |||
| def +(other : Int) | |||
| self + other.to_i64 | |||
| self + LibC::PtrdiffT.new(other) | |||
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You must hack the compiler for this to compile on 32bit platforms (Pointer#+(Int64) is a Crystal intrinsic). See below.
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Thanks for the explanation.
akzhan
changed the title
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I should close this because another approach has been landed - #4960. |
Intrinsics now declared per architecture.
LibC::PtrdiffT is the signed integer type of the result of subtracting two pointers.
LibC::PtrdiffT is used for pointer arithmetic and array indexing, if negative values are possible.
Refs #823, Closes #4589.
/cc @ysbaddaden