Rollup merge of #131807 - beetrees:riscv-target-abi, r=workingjubilee

Always specify `llvm_abiname` for RISC-V targets

For RISC-V targets, when `llvm_abiname` is not specified LLVM will infer the ABI from the target features, causing #116344 to occur. This PR adds the correct `llvm_abiname` to all RISC-V targets where it is missing (which are all soft-float targets), and adds a test to prevent future RISC-V targets from accidentally omitting `llvm_abiname`. The only affect of this PR is that `-Ctarget-feature=+f` (or similar) will no longer affect the ABI on the modified targets.

<!-- homu-ignore:start -->
r? `@RalfJung`
<!--- homu-ignore:end -->

2 files changed, 47 insertions, 1 deletions

diff --git a/tests/assembly/riscv-soft-abi-with-float-features.rs b/tests/assembly/riscv-soft-abi-with-float-features.rs
new file mode 100644
index 00000000000..733137f5700
--- /dev/null
+++ b/tests/assembly/riscv-soft-abi-with-float-features.rs
@@ -0,0 +1,46 @@
+//@ assembly-output: emit-asm
+//@ compile-flags: --target riscv64imac-unknown-none-elf -Ctarget-feature=+f,+d
+//@ needs-llvm-components: riscv
+
+#![feature(no_core, lang_items, f16)]
+#![crate_type = "lib"]
+#![no_core]
+
+#[lang = "sized"]
+trait Sized {}
+
+#[lang = "copy"]
+trait Copy {}
+
+impl Copy for f16 {}
+impl Copy for f32 {}
+impl Copy for f64 {}
+
+// This test checks that the floats are all returned in `a0` as required by the `lp64` ABI.
+
+// CHECK-LABEL: read_f16
+#[no_mangle]
+pub extern "C" fn read_f16(x: &f16) -> f16 {
+    // CHECK: lh a0, 0(a0)
+    // CHECK-NEXT: lui a1, 1048560
+    // CHECK-NEXT: or a0, a0, a1
+    // CHECK-NEXT: ret
+    *x
+}
+
+// CHECK-LABEL: read_f32
+#[no_mangle]
+pub extern "C" fn read_f32(x: &f32) -> f32 {
+    // CHECK: flw fa5, 0(a0)
+    // CHECK-NEXT: fmv.x.w a0, fa5
+    // CHECK-NEXT: ret
+    *x
+}
+
+// CHECK-LABEL: read_f64
+#[no_mangle]
+pub extern "C" fn read_f64(x: &f64) -> f64 {
+    // CHECK: ld a0, 0(a0)
+    // CHECK-NEXT: ret
+    *x
+}
diff --git a/tests/codegen/riscv-target-abi.rs b/tests/codegen/riscv-target-abi.rs
index 5d545af9c76..88da4ece7ba 100644
--- a/tests/codegen/riscv-target-abi.rs
+++ b/tests/codegen/riscv-target-abi.rs
@@ -10,7 +10,7 @@
 
 //@[riscv32imac] compile-flags: --target=riscv32imac-unknown-none-elf
 //@[riscv32imac] needs-llvm-components: riscv
-// riscv32imac-NOT: !"target-abi"
+// riscv32imac: !{i32 1, !"target-abi", !"ilp32"}
 
 #![feature(no_core, lang_items)]
 #![crate_type = "lib"]