* add `@bswap` builtin function. See #767
* comptime evaluation facilities are improved to be able to
handle a `@ptrCast` with a backing array.
* `@truncate` allows "truncating" a u0 value to any integer
type, and the result is always comptime known to be `0`.
* when specifying pointer alignment in a type expression,
the alignment value of pointers which do not have addresses
at runtime is ignored, and always has the default/ABI alignment
* threw in a fix to freebsd/x86_64.zig to update syntax from
language changes
* some improvements are pending #863closes#638closes#1733
std lib API changes
* io.InStream().readIntNe renamed to readIntNative
* io.InStream().readIntLe renamed to readIntLittle
* io.InStream().readIntBe renamed to readIntBig
* introduced io.InStream().readIntForeign
* io.InStream().readInt has parameter order changed
* io.InStream().readVarInt has parameter order changed
* io.InStream().writeIntNe renamed to writeIntNative
* introduced io.InStream().writeIntForeign
* io.InStream().writeIntLe renamed to writeIntLittle
* io.InStream().writeIntBe renamed to writeIntBig
* io.InStream().writeInt has parameter order changed
* mem.readInt has different parameters and semantics
* introduced mem.readIntNative
* introduced mem.readIntForeign
* mem.readIntBE renamed to mem.readIntBig and different API
* mem.readIntLE renamed to mem.readIntLittle and different API
* introduced mem.readIntSliceNative
* introduced mem.readIntSliceForeign
* introduced mem.readIntSliceLittle
* introduced mem.readIntSliceBig
* introduced mem.readIntSlice
* mem.writeInt has different parameters and semantics
* introduced mem.writeIntNative
* introduced mem.writeIntForeign
* mem.writeIntBE renamed to mem.readIntBig and different semantics
* mem.writeIntLE renamed to mem.readIntLittle and different semantics
* introduced mem.writeIntSliceForeign
* introduced mem.writeIntSliceNative
* introduced mem.writeIntSliceBig
* introduced mem.writeIntSliceLittle
* introduced mem.writeIntSlice
* removed mem.endianSwapIfLe
* removed mem.endianSwapIfBe
* removed mem.endianSwapIf
* added mem.littleToNative
* added mem.bigToNative
* added mem.toNative
* added mem.nativeTo
* added mem.nativeToLittle
* added mem.nativeToBig
* add __multi3 compiler rt function. See #1290
* compiler rt includes ARM functions for thumb and aarch64 and
other sub-arches left out. See #1526
* support C ABI for returning structs on ARM. see #1481
We were caching the ConstExprValue of string literals,
which works if you can never modify ConstExprValues.
This premise is broken with `comptime var ...`.
So I implemented an optimization in ConstExprValue
arrays, where it stores a `Buf *` directly rather
than an array of ConstExprValues for the elements,
and then similar to array of undefined, it is
expanded into the canonical form when necessary.
However many operations can happen directly on the
`Buf *`, which is faster.
Furthermore, before a ConstExprValue array is expanded
into canonical form, it removes itself from the string
literal cache. This fixes the issue, because before an
array element is modified it would have to be expanded.
closes#1076