Add bare metal riscv32 target.

Author: royb3

compiler/rustc_target/src/spec/mod.rs

@@ -1599,6 +1599,7 @@ supported_targets! {
     ("riscv32i-unknown-none-elf", riscv32i_unknown_none_elf),
     ("riscv32im-risc0-zkvm-elf", riscv32im_risc0_zkvm_elf),
     ("riscv32im-unknown-none-elf", riscv32im_unknown_none_elf),
+    ("riscv32ima-unknown-none-elf", riscv32ima_unknown_none_elf),
     ("riscv32imc-unknown-none-elf", riscv32imc_unknown_none_elf),
     ("riscv32imc-esp-espidf", riscv32imc_esp_espidf),
     ("riscv32imac-esp-espidf", riscv32imac_esp_espidf),

compiler/rustc_target/src/spec/targets/riscv32ima_unknown_none_elf.rs

@@ -0,0 +1,23 @@
+use crate::spec::{Cc, LinkerFlavor, Lld, PanicStrategy, RelocModel, Target, TargetOptions};
+
+pub fn target() -> Target {
+    Target {
+        data_layout: "e-m:e-p:32:32-i64:64-n32-S128".into(),
+        llvm_target: "riscv32".into(),
+        pointer_width: 32,
+        arch: "riscv32".into(),
+
+        options: TargetOptions {
+            linker_flavor: LinkerFlavor::Gnu(Cc::No, Lld::Yes),
+            linker: Some("rust-lld".into()),
+            cpu: "generic-rv32".into(),
+            max_atomic_width: Some(32),
+            features: "+m,+a".into(),
+            panic_strategy: PanicStrategy::Abort,
+            relocation_model: RelocModel::Static,
+            emit_debug_gdb_scripts: false,
+            eh_frame_header: false,
+            ..Default::default()
+        },
+    }
+}

src/doc/rustc/src/platform-support.md

@@ -339,6 +339,7 @@ target | std | host | notes
 `riscv32gc-unknown-linux-gnu` |   |   | RISC-V Linux (kernel 5.4, glibc 2.33)
 `riscv32gc-unknown-linux-musl` |   |   | RISC-V Linux (kernel 5.4, musl + RISCV32 support patches)
 [`riscv32im-risc0-zkvm-elf`](platform-support/riscv32im-risc0-zkvm-elf.md) | ? |  | RISC Zero's zero-knowledge Virtual Machine (RV32IM ISA)
+[`riscv32ima-unknown-none-elf`](platform-support/riscv32imac-unknown-none-elf.md) | * |  | Bare RISC-V (RV32IMA ISA)
 [`riscv32imac-unknown-xous-elf`](platform-support/riscv32imac-unknown-xous-elf.md) | ? |  | RISC-V Xous (RV32IMAC ISA)
 [`riscv32imc-esp-espidf`](platform-support/esp-idf.md) | ✓ |  | RISC-V ESP-IDF
 [`riscv32imac-esp-espidf`](platform-support/esp-idf.md) | ✓ |  | RISC-V ESP-IDF

src/doc/rustc/src/platform-support/riscv32ima-unknown-none-elf.md

@@ -0,0 +1 @@
+riscv32imac-unknown-none-elf.md

src/doc/rustc/src/platform-support/riscv32imac-unknown-none-elf.md

@@ -2,7 +2,7 @@
 
 **Tier: 2**
 
-Bare-metal target for RISC-V CPUs with the RV32I, RV32IM, RV32IMC, RV32IMAFC and RV32IMAC ISAs.
+Bare-metal target for RISC-V CPUs with the RV32I, RV32IM, RV32IMA, RV32IMC, RV32IMAFC and RV32IMAC ISAs.
 
 ## Target maintainers
 

src/tools/build-manifest/src/main.rs

@@ -123,6 +123,7 @@ static TARGETS: &[&str] = &[
     "riscv32i-unknown-none-elf",
     "riscv32im-risc0-zkvm-elf",
     "riscv32im-unknown-none-elf",
+    "riscv32ima-unknown-none-elf",
     "riscv32imc-unknown-none-elf",
     "riscv32imac-unknown-none-elf",
     "riscv32imafc-unknown-none-elf",

tests/assembly/targets/targets-elf.rs

@@ -363,6 +363,9 @@
 // revisions: riscv32im_unknown_none_elf
 // [riscv32im_unknown_none_elf] compile-flags: --target riscv32im-unknown-none-elf
 // [riscv32im_unknown_none_elf] needs-llvm-components: riscv
+// revisions: riscv32ima_unknown_none_elf
+// [riscv32ima_unknown_none_elf] compile-flags: --target riscv32ima-unknown-none-elf
+// [riscv32ima_unknown_none_elf] needs-llvm-components: riscv
 // revisions: riscv32imac_esp_espidf
 // [riscv32imac_esp_espidf] compile-flags: --target riscv32imac-esp-espidf
 // [riscv32imac_esp_espidf] needs-llvm-components: riscv