From 59f01cdbf48795ab8d6752b8a4bbe0e4540c30a5 Mon Sep 17 00:00:00 2001
From: Taiki Endo <te316e89@gmail.com>
Date: Mon, 25 Nov 2024 23:11:17 +0900
Subject: [PATCH] Support predicate registers (clobber-only) in Hexagon inline
assembly
---
compiler/rustc_codegen_gcc/src/asm.rs | 6 +++
compiler/rustc_codegen_llvm/src/asm.rs | 2 +
compiler/rustc_target/src/asm/hexagon.rs | 6 +++
.../asm-experimental-arch.md | 2 +
tests/codegen/asm/hexagon-clobbers.rs | 37 +++++++++++++++++++
5 files changed, 53 insertions(+)
create mode 100644 tests/codegen/asm/hexagon-clobbers.rs
diff --git a/compiler/rustc_codegen_gcc/src/asm.rs b/compiler/rustc_codegen_gcc/src/asm.rs
index ab4fdb78bb0..341d1b9c179 100644
--- a/compiler/rustc_codegen_gcc/src/asm.rs
+++ b/compiler/rustc_codegen_gcc/src/asm.rs
@@ -634,6 +634,9 @@ fn reg_to_gcc(reg: InlineAsmRegOrRegClass) -> ConstraintOrRegister {
InlineAsmRegClass::Bpf(BpfInlineAsmRegClass::reg) => "r",
InlineAsmRegClass::Bpf(BpfInlineAsmRegClass::wreg) => "w",
InlineAsmRegClass::Hexagon(HexagonInlineAsmRegClass::reg) => "r",
+ InlineAsmRegClass::Hexagon(HexagonInlineAsmRegClass::preg) => {
+ unreachable!("clobber-only")
+ }
InlineAsmRegClass::LoongArch(LoongArchInlineAsmRegClass::reg) => "r",
InlineAsmRegClass::LoongArch(LoongArchInlineAsmRegClass::freg) => "f",
InlineAsmRegClass::M68k(M68kInlineAsmRegClass::reg) => "r",
@@ -720,6 +723,9 @@ fn dummy_output_type<'gcc, 'tcx>(cx: &CodegenCx<'gcc, 'tcx>, reg: InlineAsmRegCl
cx.type_vector(cx.type_i64(), 2)
}
InlineAsmRegClass::Hexagon(HexagonInlineAsmRegClass::reg) => cx.type_i32(),
+ InlineAsmRegClass::Hexagon(HexagonInlineAsmRegClass::preg) => {
+ unreachable!("clobber-only")
+ }
InlineAsmRegClass::LoongArch(LoongArchInlineAsmRegClass::reg) => cx.type_i32(),
InlineAsmRegClass::LoongArch(LoongArchInlineAsmRegClass::freg) => cx.type_f32(),
InlineAsmRegClass::Mips(MipsInlineAsmRegClass::reg) => cx.type_i32(),
diff --git a/compiler/rustc_codegen_llvm/src/asm.rs b/compiler/rustc_codegen_llvm/src/asm.rs
index 6ee80c08d4a..9aa01bd1b95 100644
--- a/compiler/rustc_codegen_llvm/src/asm.rs
+++ b/compiler/rustc_codegen_llvm/src/asm.rs
@@ -645,6 +645,7 @@ fn reg_to_llvm(reg: InlineAsmRegOrRegClass, layout: Option<&TyAndLayout<'_>>) ->
| Arm(ArmInlineAsmRegClass::qreg_low4) => "x",
Arm(ArmInlineAsmRegClass::dreg) | Arm(ArmInlineAsmRegClass::qreg) => "w",
Hexagon(HexagonInlineAsmRegClass::reg) => "r",
+ Hexagon(HexagonInlineAsmRegClass::preg) => unreachable!("clobber-only"),
LoongArch(LoongArchInlineAsmRegClass::reg) => "r",
LoongArch(LoongArchInlineAsmRegClass::freg) => "f",
Mips(MipsInlineAsmRegClass::reg) => "r",
@@ -813,6 +814,7 @@ fn dummy_output_type<'ll>(cx: &CodegenCx<'ll, '_>, reg: InlineAsmRegClass) -> &'
| Arm(ArmInlineAsmRegClass::qreg_low8)
| Arm(ArmInlineAsmRegClass::qreg_low4) => cx.type_vector(cx.type_i64(), 2),
Hexagon(HexagonInlineAsmRegClass::reg) => cx.type_i32(),
+ Hexagon(HexagonInlineAsmRegClass::preg) => unreachable!("clobber-only"),
LoongArch(LoongArchInlineAsmRegClass::reg) => cx.type_i32(),
LoongArch(LoongArchInlineAsmRegClass::freg) => cx.type_f32(),
Mips(MipsInlineAsmRegClass::reg) => cx.type_i32(),
diff --git a/compiler/rustc_target/src/asm/hexagon.rs b/compiler/rustc_target/src/asm/hexagon.rs
index f7e726c3376..aa14ca3f337 100644
--- a/compiler/rustc_target/src/asm/hexagon.rs
+++ b/compiler/rustc_target/src/asm/hexagon.rs
@@ -7,6 +7,7 @@ use super::{InlineAsmArch, InlineAsmType, ModifierInfo};
def_reg_class! {
Hexagon HexagonInlineAsmRegClass {
reg,
+ preg,
}
}
@@ -37,6 +38,7 @@ impl HexagonInlineAsmRegClass {
) -> &'static [(InlineAsmType, Option<Symbol>)] {
match self {
Self::reg => types! { _: I8, I16, I32, F32; },
+ Self::preg => &[],
}
}
}
@@ -71,6 +73,10 @@ def_regs! {
r26: reg = ["r26"],
r27: reg = ["r27"],
r28: reg = ["r28"],
+ p0: preg = ["p0"],
+ p1: preg = ["p1"],
+ p2: preg = ["p2"],
+ p3: preg = ["p3"],
#error = ["r19"] =>
"r19 is used internally by LLVM and cannot be used as an operand for inline asm",
#error = ["r29", "sp"] =>
diff --git a/src/doc/unstable-book/src/language-features/asm-experimental-arch.md b/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
index 01de12bb90e..12a73f0508b 100644
--- a/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
+++ b/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
@@ -30,6 +30,7 @@ This feature tracks `asm!` and `global_asm!` support for the following architect
| NVPTX | `reg32` | None\* | `r` |
| NVPTX | `reg64` | None\* | `l` |
| Hexagon | `reg` | `r[0-28]` | `r` |
+| Hexagon | `preg` | `p[0-3]` | Only clobbers |
| PowerPC | `reg` | `r0`, `r[3-12]`, `r[14-28]` | `r` |
| PowerPC | `reg_nonzero` | `r[3-12]`, `r[14-28]` | `b` |
| PowerPC | `freg` | `f[0-31]` | `f` |
@@ -70,6 +71,7 @@ This feature tracks `asm!` and `global_asm!` support for the following architect
| NVPTX | `reg32` | None | `i8`, `i16`, `i32`, `f32` |
| NVPTX | `reg64` | None | `i8`, `i16`, `i32`, `f32`, `i64`, `f64` |
| Hexagon | `reg` | None | `i8`, `i16`, `i32`, `f32` |
+| Hexagon | `preg` | N/A | Only clobbers |
| PowerPC | `reg` | None | `i8`, `i16`, `i32`, `i64` (powerpc64 only) |
| PowerPC | `reg_nonzero` | None | `i8`, `i16`, `i32`, `i64` (powerpc64 only) |
| PowerPC | `freg` | None | `f32`, `f64` |
diff --git a/tests/codegen/asm/hexagon-clobbers.rs b/tests/codegen/asm/hexagon-clobbers.rs
new file mode 100644
index 00000000000..6bb662ead99
--- /dev/null
+++ b/tests/codegen/asm/hexagon-clobbers.rs
@@ -0,0 +1,37 @@
+//@ revisions: hexagon
+//@[hexagon] compile-flags: --target hexagon-unknown-linux-musl
+//@[hexagon] needs-llvm-components: hexagon
+//@ compile-flags: -Zmerge-functions=disabled
+
+#![crate_type = "rlib"]
+#![feature(no_core, rustc_attrs, lang_items, asm_experimental_arch)]
+#![no_core]
+
+#[lang = "sized"]
+trait Sized {}
+
+#[rustc_builtin_macro]
+macro_rules! asm {
+ () => {};
+}
+
+// CHECK-LABEL: @flags_clobber
+// CHECK: call void asm sideeffect "", ""()
+#[no_mangle]
+pub unsafe fn flags_clobber() {
+ asm!("", options(nostack, nomem));
+}
+
+// CHECK-LABEL: @no_clobber
+// CHECK: call void asm sideeffect "", ""()
+#[no_mangle]
+pub unsafe fn no_clobber() {
+ asm!("", options(nostack, nomem, preserves_flags));
+}
+
+// CHECK-LABEL: @p0_clobber
+// CHECK: call void asm sideeffect "", "~{p0}"()
+#[no_mangle]
+pub unsafe fn p0_clobber() {
+ asm!("", out("p0") _, options(nostack, nomem, preserves_flags));
+}