By placing the stack at the start of the memory section, we prevent the runtime
from silently overwriting the global declarations and instead trap.
We do however, allow users to overwrite this behavior by setting the global-base,
which puts the stack at the end of the memory section and the static data at the base that was specified.
The reason a user would want to do this, is when they are sure the stack will not overflow and they want
to decrease the binary size as the offsets to the static memory are generally smaller.
(Having the stack in front, means that accessing the memory after the stack has a bigger offset when loading/storing from memory).
This allows users to add file paths to device paths, which is often used
in methods like `boot_services.loadImage` and `boot_services.startImage`,
which take a device path with an additional file path appended to locate
the image.
UEFI uses `\` for paths exclusively. This changes std.fs.path to use `\`
for UEFI path joining. Also adds a few tests regarding it, specifically
in making sure double-separators do not result from path joining, as the
UEFI spec says to convert any that result from joining into single
separators (UEFI Spec Version 2.7, pg. 448).
Prior to this change, even if the use specified the sysroot on the
compiler line like so
```
zig cc --sysroot=/path/to/sdk
```
it would only be used as a prefix to include paths and not as a prefix
for `zig ld` linker.
- Add an `Metadata.isFree` helper method.
- Implement `Metadata.isTombstone` and `Metadata.isFree` with `@bitCast` then comparing to a constant. I assume `@bitCast`-then-compare is faster than the old method because it only involves one comparison, and doesn't require bitmasking.
- Summary of benchmarked changes (`gotta-go-fast`, run locally, compared to master):
- 3/4 of the hash map benchmarks used ~10% fewer cycles
- The last one (project Euler) shows 4% fewer cycles.
- This implements the float_to_int AIR instruction.
- Lowering a decl_ref to a slice was previously assumed to contain a pointer
to a slice, rather than an array. This is now fixed, making `@src()` work as well.
- Some preliminary work on 128bit integers have been done to find out what needs to be done
to implement 128bit arithmetic.
* stage2: put decls in different MachO sections
Use `getDeclVAddrWithReloc` when targeting MachO backend rather than
`getDeclVAddr` - this fn returns a zero vaddr and instead creates a
relocation on the linker side which will get automatically updated
whenever the target decl is moved in memory. This fn also records
a rebase of the target pointer so that its value is correctly slid
in presence of ASLR.
This commit enables `zig test` on x86_64-macos.
* stage2: fix output section selection for type,val pairs
It is possible for Zig to emit field ptr instructions to fields whos
type is zero sized. In this case llvm should return a pointer which
points to the next none zero sized parameter.
`runtime_param_index` is used to get the parameter type from `fn_type`,
but this variable was not incremented for zero sized parameters, causing
two zero sized parameters of different type to cause miss complication.
resolveTypeForCodegen is called when we needed to resolve a type fully,
even through pointer. This commit fully implements this, even through
pointer fields on structs and unions.
The function has now also been renamed to resolveTypeFully
