compiler: Set target_abi = "ilp32e" on all riscv32e targets

This allows compile-time configuration based on this.
In the near future we should do this across all RISCV targets, probably,
but this cfg is essential for building software usable on these targets.

Author: workingjubilee

compiler/rustc_target/src/spec/targets/riscv32e_unknown_none_elf.rs

@@ -1,6 +1,7 @@
 use crate::spec::{Cc, LinkerFlavor, Lld, PanicStrategy, RelocModel, Target, TargetOptions};
 
 pub(crate) fn target() -> Target {
+    let abi = "ilp32e";
     Target {
         // The below `data_layout` is explicitly specified by the ilp32e ABI in LLVM. See also
         // `options.llvm_abiname`.
@@ -16,11 +17,12 @@ pub(crate) fn target() -> Target {
         arch: "riscv32".into(),
 
         options: TargetOptions {
+            abi: abi.into(),
             linker_flavor: LinkerFlavor::Gnu(Cc::No, Lld::Yes),
             linker: Some("rust-lld".into()),
             cpu: "generic-rv32".into(),
             // The ilp32e ABI specifies the `data_layout`
-            llvm_abiname: "ilp32e".into(),
+            llvm_abiname: abi.into(),
             max_atomic_width: Some(32),
             atomic_cas: false,
             features: "+e,+forced-atomics".into(),

compiler/rustc_target/src/spec/targets/riscv32em_unknown_none_elf.rs

@@ -1,6 +1,7 @@
 use crate::spec::{Cc, LinkerFlavor, Lld, PanicStrategy, RelocModel, Target, TargetOptions};
 
 pub(crate) fn target() -> Target {
+    let abi = "ilp32e";
     Target {
         // The below `data_layout` is explicitly specified by the ilp32e ABI in LLVM. See also
         // `options.llvm_abiname`.
@@ -16,11 +17,12 @@ pub(crate) fn target() -> Target {
         arch: "riscv32".into(),
 
         options: TargetOptions {
+            abi: abi.into(),
             linker_flavor: LinkerFlavor::Gnu(Cc::No, Lld::Yes),
             linker: Some("rust-lld".into()),
             cpu: "generic-rv32".into(),
             // The ilp32e ABI specifies the `data_layout`
-            llvm_abiname: "ilp32e".into(),
+            llvm_abiname: abi.into(),
             max_atomic_width: Some(32),
             atomic_cas: false,
             features: "+e,+m,+forced-atomics".into(),

compiler/rustc_target/src/spec/targets/riscv32emc_unknown_none_elf.rs

@@ -1,6 +1,7 @@
 use crate::spec::{Cc, LinkerFlavor, Lld, PanicStrategy, RelocModel, Target, TargetOptions};
 
 pub(crate) fn target() -> Target {
+    let abi = "ilp32e";
     Target {
         // The below `data_layout` is explicitly specified by the ilp32e ABI in LLVM. See also
         // `options.llvm_abiname`.
@@ -16,11 +17,12 @@ pub(crate) fn target() -> Target {
         arch: "riscv32".into(),
 
         options: TargetOptions {
+            abi: abi.into(),
             linker_flavor: LinkerFlavor::Gnu(Cc::No, Lld::Yes),
             linker: Some("rust-lld".into()),
             cpu: "generic-rv32".into(),
             // The ilp32e ABI specifies the `data_layout`
-            llvm_abiname: "ilp32e".into(),
+            llvm_abiname: abi.into(),
             max_atomic_width: Some(32),
             atomic_cas: false,
             features: "+e,+m,+c,+forced-atomics".into(),

tests/ui/check-cfg/well-known-values.stderr

@@ -129,7 +129,7 @@ warning: unexpected `cfg` condition value: `_UNEXPECTED_VALUE`
 LL |     target_abi = "_UNEXPECTED_VALUE",
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: expected values for `target_abi` are: ``, `abi64`, `abiv2`, `abiv2hf`, `eabi`, `eabihf`, `fortanix`, `ilp32`, `llvm`, `macabi`, `sim`, `softfloat`, `spe`, `uwp`, `vec-extabi`, and `x32`
+   = note: expected values for `target_abi` are: ``, `abi64`, `abiv2`, `abiv2hf`, `eabi`, `eabihf`, `fortanix`, `ilp32`, `ilp32e`, `llvm`, `macabi`, `sim`, `softfloat`, `spe`, `uwp`, `vec-extabi`, and `x32`
    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more information about checking conditional configuration
 
 warning: unexpected `cfg` condition value: `_UNEXPECTED_VALUE`