Skip to content

Add X86 target support for NuttX #136181

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 1 commit into from
Closed
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 2 additions & 0 deletions compiler/rustc_target/src/spec/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -2004,6 +2004,8 @@ supported_targets! {

("x86_64-unknown-linux-none", x86_64_unknown_linux_none),

("i686-unknown-nuttx", i686_unknown_nuttx),
("x86_64-unknown-nuttx", x86_64_unknown_nuttx),
("thumbv6m-nuttx-eabi", thumbv6m_nuttx_eabi),
("thumbv7a-nuttx-eabi", thumbv7a_nuttx_eabi),
("thumbv7a-nuttx-eabihf", thumbv7a_nuttx_eabihf),
Expand Down
37 changes: 37 additions & 0 deletions compiler/rustc_target/src/spec/targets/i686_unknown_nuttx.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,37 @@
use crate::spec::{Cc, LinkerFlavor, Lld, RelocModel, StackProbeType, Target, TargetOptions, cvs};

pub(crate) fn target() -> Target {
let mut base = TargetOptions {
os: "nuttx".into(),
dynamic_linking: false,
families: cvs!["unix"],
no_default_libraries: true,
has_rpath: false,
position_independent_executables: false,
relocation_model: RelocModel::Static,
relro_level: crate::spec::RelroLevel::Full,
has_thread_local: true,
use_ctors_section: true,
..Default::default()
};
base.cpu = "pentium4".into();
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This is not an i486 CPU, this is a 32-bit x86 CPU with SSE2 registers.

base.max_atomic_width = Some(64);
base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m32"]);
base.stack_probes = StackProbeType::Inline;

Target {
llvm_target: "i686-unknown-nuttx".into(),
metadata: crate::spec::TargetMetadata {
description: Some("NuttX/x86".into()),
tier: Some(3),
host_tools: Some(false),
std: Some(true),
},
pointer_width: 32,
data_layout: "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-\
i128:128-f64:32:64-f80:32-n8:16:32-S128"
.into(),
arch: "x86".into(),
options: base,
}
}
41 changes: 41 additions & 0 deletions compiler/rustc_target/src/spec/targets/x86_64_unknown_nuttx.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,41 @@
// Generic x86-64 target for NuttX RTOS
//
// Can be used in conjunction with the `target-feature` and
// `target-cpu` compiler flags to opt-in more hardware-specific
// features.

use crate::spec::{RelocModel, StackProbeType, Target, TargetOptions, cvs};

pub(crate) fn target() -> Target {
let mut base = TargetOptions {
os: "nuttx".into(),
dynamic_linking: false,
families: cvs!["unix"],
no_default_libraries: true,
has_rpath: false,
position_independent_executables: false,
relocation_model: RelocModel::Static,
relro_level: crate::spec::RelroLevel::Full,
has_thread_local: true,
use_ctors_section: true,
..Default::default()
};
base.cpu = "x86-64".into();
base.max_atomic_width = Some(64);
base.stack_probes = StackProbeType::Inline;

Target {
llvm_target: "x86_64-unknown-nuttx".into(),
metadata: crate::spec::TargetMetadata {
description: Some("NuttX/x86_64".into()),
tier: Some(3),
host_tools: Some(false),
std: Some(true),
},
pointer_width: 64,
data_layout:
"e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128".into(),
arch: "x86_64".into(),
options: base,
}
}
2 changes: 2 additions & 0 deletions src/doc/rustc/src/platform-support.md
Original file line number Diff line number Diff line change
Expand Up @@ -314,6 +314,7 @@ target | std | host | notes
`i686-unknown-haiku` | ✓ | ✓ | 32-bit Haiku (Pentium 4) [^x86_32-floats-return-ABI]
[`i686-unknown-hurd-gnu`](platform-support/hurd.md) | ✓ | ✓ | 32-bit GNU/Hurd (PentiumPro) [^x86_32-floats-x87]
[`i686-unknown-netbsd`](platform-support/netbsd.md) | ✓ | ✓ | NetBSD/i386 (Pentium 4) [^x86_32-floats-return-ABI]
[`i686-unknown-nuttx`](platform-support/nuttx.md) | ✓ | | 32-bit x86 with NuttX
[`i686-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 32-bit OpenBSD (Pentium 4) [^x86_32-floats-return-ABI]
[`i686-unknown-redox`](platform-support/redox.md) | ✓ | | i686 Redox OS (PentiumPro) [^x86_32-floats-x87]
`i686-uwp-windows-gnu` | ✓ | | [^x86_32-floats-return-ABI]
Expand Down Expand Up @@ -417,6 +418,7 @@ target | std | host | notes
`x86_64-unknown-l4re-uclibc` | ? | |
[`x86_64-unknown-linux-none`](platform-support/x86_64-unknown-linux-none.md) | * | | 64-bit Linux with no libc
[`x86_64-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 64-bit OpenBSD
[`x86_64-unknown-nuttx`](platform-support/nuttx.md) | ✓ | | 64-bit x86 with NuttX
[`x86_64-unknown-trusty`](platform-support/trusty.md) | ? | |
`x86_64-uwp-windows-gnu` | ✓ | |
[`x86_64-uwp-windows-msvc`](platform-support/uwp-windows-msvc.md) | ✓ | |
Expand Down
13 changes: 12 additions & 1 deletion src/doc/rustc/src/platform-support/nuttx.md
Original file line number Diff line number Diff line change
Expand Up @@ -20,6 +20,8 @@ The target name follow this format: `ARCH[-VENDOR]-nuttx-ABI`, where `ARCH` is t

The following target names are defined:

- `i686-unknown-nuttx`
- `x86_64-unknown-nuttx`
- `aarch64-unknown-nuttx`
- `armv7a-nuttx-eabi`
- `armv7a-nuttx-eabihf`
Expand Down Expand Up @@ -52,13 +54,22 @@ linker = "riscv-none-elf-gcc"

The toolchain for the target can be found in [NuttX's quick start guide](https://nuttx.apache.org/docs/latest/quickstart/install.html).


## Testing

This is a cross-compiled `no-std` target, which must be run either in a simulator
or by programming them onto suitable hardware. It is not possible to run the
Rust test-suite on this target.

## Note for Floating-Point support on X86/X86_64

For the NuttX platform, X86/X86_64 targets have two usage scenarios:
1. Linked to a "SIM" running in a POSIX environment (more common)
2. Running directly on baremetal hardware

In the SIM environment, the FPU (Floating Point Unit) configuration is fixed and not configurable. For baremetal scenarios:
- On i686 (targeting i486 in NuttX), the FPU is typically disabled
- On x86_64, the FPU is enabled by default but can be disabled if needed
Comment on lines +70 to +71
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

According to Rust, only one of these can be true per target. Pick.


## Cross-compilation toolchains and C code

This target supports C code. If interlinking with C or C++, you may need to use
Expand Down
6 changes: 6 additions & 0 deletions tests/assembly/targets/targets-elf.rs
Original file line number Diff line number Diff line change
Expand Up @@ -249,6 +249,9 @@
//@ revisions: i686_unknown_netbsd
//@ [i686_unknown_netbsd] compile-flags: --target i686-unknown-netbsd
//@ [i686_unknown_netbsd] needs-llvm-components: x86
//@ revisions: i686_unknown_nuttx
//@ [i686_unknown_nuttx] compile-flags: --target i686-unknown-nuttx
//@ [i686_unknown_nuttx] needs-llvm-components: x86
//@ revisions: i686_unknown_openbsd
//@ [i686_unknown_openbsd] compile-flags: --target i686-unknown-openbsd
//@ [i686_unknown_openbsd] needs-llvm-components: x86
Expand Down Expand Up @@ -627,6 +630,9 @@
//@ revisions: x86_64_unknown_none
//@ [x86_64_unknown_none] compile-flags: --target x86_64-unknown-none
//@ [x86_64_unknown_none] needs-llvm-components: x86
//@ revisions: x86_64_unknown_nuttx
//@ [x86_64_unknown_nuttx] compile-flags: --target x86_64-unknown-nuttx
//@ [x86_64_unknown_nuttx] needs-llvm-components: x86
//@ revisions: x86_64_unknown_openbsd
//@ [x86_64_unknown_openbsd] compile-flags: --target x86_64-unknown-openbsd
//@ [x86_64_unknown_openbsd] needs-llvm-components: x86
Expand Down
Loading