Auto merge of #88245 - Sl1mb0:s390-asm, r=Amanieu

S390x inline asm

This adds register definitions and constraint codes for the s390x general and floating point registers necessary for fixing #85931; as well as a few tests.

Further testing is needed, but I am a little unsure of what specific tests should be added to `src/test/assembly/asm/s390x.rs` to address this.

2 files changed, 131 insertions, 0 deletions

diff --git a/compiler/rustc_target/src/asm/mod.rs b/compiler/rustc_target/src/asm/mod.rs
index bb24f7bb135..fb23e5c85a1 100644
--- a/compiler/rustc_target/src/asm/mod.rs
+++ b/compiler/rustc_target/src/asm/mod.rs
@@ -154,6 +154,7 @@ mod mips;
 mod nvptx;
 mod powerpc;
 mod riscv;
+mod s390x;
 mod spirv;
 mod wasm;
 mod x86;
@@ -166,6 +167,7 @@ pub use mips::{MipsInlineAsmReg, MipsInlineAsmRegClass};
 pub use nvptx::{NvptxInlineAsmReg, NvptxInlineAsmRegClass};
 pub use powerpc::{PowerPCInlineAsmReg, PowerPCInlineAsmRegClass};
 pub use riscv::{RiscVInlineAsmReg, RiscVInlineAsmRegClass};
+pub use s390x::{S390xInlineAsmReg, S390xInlineAsmRegClass};
 pub use spirv::{SpirVInlineAsmReg, SpirVInlineAsmRegClass};
 pub use wasm::{WasmInlineAsmReg, WasmInlineAsmRegClass};
 pub use x86::{X86InlineAsmReg, X86InlineAsmRegClass};
@@ -184,6 +186,7 @@ pub enum InlineAsmArch {
     Mips64,
     PowerPC,
     PowerPC64,
+    S390x,
     SpirV,
     Wasm32,
     Bpf,
@@ -206,6 +209,7 @@ impl FromStr for InlineAsmArch {
             "hexagon" => Ok(Self::Hexagon),
             "mips" => Ok(Self::Mips),
             "mips64" => Ok(Self::Mips64),
+            "s390x" => Ok(Self::S390x),
             "spirv" => Ok(Self::SpirV),
             "wasm32" => Ok(Self::Wasm32),
             "bpf" => Ok(Self::Bpf),
@@ -235,6 +239,7 @@ pub enum InlineAsmReg {
     PowerPC(PowerPCInlineAsmReg),
     Hexagon(HexagonInlineAsmReg),
     Mips(MipsInlineAsmReg),
+    S390x(S390xInlineAsmReg),
     SpirV(SpirVInlineAsmReg),
     Wasm(WasmInlineAsmReg),
     Bpf(BpfInlineAsmReg),
@@ -252,6 +257,7 @@ impl InlineAsmReg {
             Self::PowerPC(r) => r.name(),
             Self::Hexagon(r) => r.name(),
             Self::Mips(r) => r.name(),
+            Self::S390x(r) => r.name(),
             Self::Bpf(r) => r.name(),
             Self::Err => "<reg>",
         }
@@ -266,6 +272,7 @@ impl InlineAsmReg {
             Self::PowerPC(r) => InlineAsmRegClass::PowerPC(r.reg_class()),
             Self::Hexagon(r) => InlineAsmRegClass::Hexagon(r.reg_class()),
             Self::Mips(r) => InlineAsmRegClass::Mips(r.reg_class()),
+            Self::S390x(r) => InlineAsmRegClass::S390x(r.reg_class()),
             Self::Bpf(r) => InlineAsmRegClass::Bpf(r.reg_class()),
             Self::Err => InlineAsmRegClass::Err,
         }
@@ -305,6 +312,9 @@ impl InlineAsmReg {
             InlineAsmArch::Mips | InlineAsmArch::Mips64 => {
                 Self::Mips(MipsInlineAsmReg::parse(arch, has_feature, target, &name)?)
             }
+            InlineAsmArch::S390x => {
+                Self::S390x(S390xInlineAsmReg::parse(arch, has_feature, target, &name)?)
+            }
             InlineAsmArch::SpirV => {
                 Self::SpirV(SpirVInlineAsmReg::parse(arch, has_feature, target, &name)?)
             }
@@ -333,6 +343,7 @@ impl InlineAsmReg {
             Self::PowerPC(r) => r.emit(out, arch, modifier),
             Self::Hexagon(r) => r.emit(out, arch, modifier),
             Self::Mips(r) => r.emit(out, arch, modifier),
+            Self::S390x(r) => r.emit(out, arch, modifier),
             Self::Bpf(r) => r.emit(out, arch, modifier),
             Self::Err => unreachable!("Use of InlineAsmReg::Err"),
         }
@@ -347,6 +358,7 @@ impl InlineAsmReg {
             Self::PowerPC(_) => cb(self),
             Self::Hexagon(r) => r.overlapping_regs(|r| cb(Self::Hexagon(r))),
             Self::Mips(_) => cb(self),
+            Self::S390x(_) => cb(self),
             Self::Bpf(r) => r.overlapping_regs(|r| cb(Self::Bpf(r))),
             Self::Err => unreachable!("Use of InlineAsmReg::Err"),
         }
@@ -374,6 +386,7 @@ pub enum InlineAsmRegClass {
     PowerPC(PowerPCInlineAsmRegClass),
     Hexagon(HexagonInlineAsmRegClass),
     Mips(MipsInlineAsmRegClass),
+    S390x(S390xInlineAsmRegClass),
     SpirV(SpirVInlineAsmRegClass),
     Wasm(WasmInlineAsmRegClass),
     Bpf(BpfInlineAsmRegClass),
@@ -392,6 +405,7 @@ impl InlineAsmRegClass {
             Self::PowerPC(r) => r.name(),
             Self::Hexagon(r) => r.name(),
             Self::Mips(r) => r.name(),
+            Self::S390x(r) => r.name(),
             Self::SpirV(r) => r.name(),
             Self::Wasm(r) => r.name(),
             Self::Bpf(r) => r.name(),
@@ -412,6 +426,7 @@ impl InlineAsmRegClass {
             Self::PowerPC(r) => r.suggest_class(arch, ty).map(InlineAsmRegClass::PowerPC),
             Self::Hexagon(r) => r.suggest_class(arch, ty).map(InlineAsmRegClass::Hexagon),
             Self::Mips(r) => r.suggest_class(arch, ty).map(InlineAsmRegClass::Mips),
+            Self::S390x(r) => r.suggest_class(arch, ty).map(InlineAsmRegClass::S390x),
             Self::SpirV(r) => r.suggest_class(arch, ty).map(InlineAsmRegClass::SpirV),
             Self::Wasm(r) => r.suggest_class(arch, ty).map(InlineAsmRegClass::Wasm),
             Self::Bpf(r) => r.suggest_class(arch, ty).map(InlineAsmRegClass::Bpf),
@@ -439,6 +454,7 @@ impl InlineAsmRegClass {
             Self::PowerPC(r) => r.suggest_modifier(arch, ty),
             Self::Hexagon(r) => r.suggest_modifier(arch, ty),
             Self::Mips(r) => r.suggest_modifier(arch, ty),
+            Self::S390x(r) => r.suggest_modifier(arch, ty),
             Self::SpirV(r) => r.suggest_modifier(arch, ty),
             Self::Wasm(r) => r.suggest_modifier(arch, ty),
             Self::Bpf(r) => r.suggest_modifier(arch, ty),
@@ -462,6 +478,7 @@ impl InlineAsmRegClass {
             Self::PowerPC(r) => r.default_modifier(arch),
             Self::Hexagon(r) => r.default_modifier(arch),
             Self::Mips(r) => r.default_modifier(arch),
+            Self::S390x(r) => r.default_modifier(arch),
             Self::SpirV(r) => r.default_modifier(arch),
             Self::Wasm(r) => r.default_modifier(arch),
             Self::Bpf(r) => r.default_modifier(arch),
@@ -484,6 +501,7 @@ impl InlineAsmRegClass {
             Self::PowerPC(r) => r.supported_types(arch),
             Self::Hexagon(r) => r.supported_types(arch),
             Self::Mips(r) => r.supported_types(arch),
+            Self::S390x(r) => r.supported_types(arch),
             Self::SpirV(r) => r.supported_types(arch),
             Self::Wasm(r) => r.supported_types(arch),
             Self::Bpf(r) => r.supported_types(arch),
@@ -509,6 +527,7 @@ impl InlineAsmRegClass {
             InlineAsmArch::Mips | InlineAsmArch::Mips64 => {
                 Self::Mips(MipsInlineAsmRegClass::parse(arch, name)?)
             }
+            InlineAsmArch::S390x => Self::S390x(S390xInlineAsmRegClass::parse(arch, name)?),
             InlineAsmArch::SpirV => Self::SpirV(SpirVInlineAsmRegClass::parse(arch, name)?),
             InlineAsmArch::Wasm32 => Self::Wasm(WasmInlineAsmRegClass::parse(arch, name)?),
             InlineAsmArch::Bpf => Self::Bpf(BpfInlineAsmRegClass::parse(arch, name)?),
@@ -527,6 +546,7 @@ impl InlineAsmRegClass {
             Self::PowerPC(r) => r.valid_modifiers(arch),
             Self::Hexagon(r) => r.valid_modifiers(arch),
             Self::Mips(r) => r.valid_modifiers(arch),
+            Self::S390x(r) => r.valid_modifiers(arch),
             Self::SpirV(r) => r.valid_modifiers(arch),
             Self::Wasm(r) => r.valid_modifiers(arch),
             Self::Bpf(r) => r.valid_modifiers(arch),
@@ -695,6 +715,11 @@ pub fn allocatable_registers(
             mips::fill_reg_map(arch, has_feature, target, &mut map);
             map
         }
+        InlineAsmArch::S390x => {
+            let mut map = s390x::regclass_map();
+            s390x::fill_reg_map(arch, has_feature, target, &mut map);
+            map
+        }
         InlineAsmArch::SpirV => {
             let mut map = spirv::regclass_map();
             spirv::fill_reg_map(arch, has_feature, target, &mut map);
diff --git a/compiler/rustc_target/src/asm/s390x.rs b/compiler/rustc_target/src/asm/s390x.rs
new file mode 100644
index 00000000000..a74873f1747
--- /dev/null
+++ b/compiler/rustc_target/src/asm/s390x.rs
@@ -0,0 +1,106 @@
+use super::{InlineAsmArch, InlineAsmType};
+use rustc_macros::HashStable_Generic;
+use std::fmt;
+
+def_reg_class! {
+    S390x S390xInlineAsmRegClass {
+        reg,
+        freg,
+    }
+}
+
+impl S390xInlineAsmRegClass {
+    pub fn valid_modifiers(self, _arch: super::InlineAsmArch) -> &'static [char] {
+        &[]
+    }
+
+    pub fn suggest_class(self, _arch: InlineAsmArch, _ty: InlineAsmType) -> Option<Self> {
+        None
+    }
+
+    pub fn suggest_modifier(
+        self,
+        _arch: InlineAsmArch,
+        _ty: InlineAsmType,
+    ) -> Option<(char, &'static str)> {
+        None
+    }
+
+    pub fn default_modifier(self, _arch: InlineAsmArch) -> Option<(char, &'static str)> {
+        None
+    }
+
+    pub fn supported_types(
+        self,
+        arch: InlineAsmArch,
+    ) -> &'static [(InlineAsmType, Option<&'static str>)] {
+        match (self, arch) {
+            (Self::reg, _) => types! { _: I8, I16, I32, I64; },
+            (Self::freg, _) => types! { _: F32, F64; },
+        }
+    }
+}
+
+def_regs! {
+    S390x S390xInlineAsmReg S390xInlineAsmRegClass {
+        r0: reg = ["r0"],
+        r1: reg = ["r1"],
+        r2: reg = ["r2"],
+        r3: reg = ["r3"],
+        r4: reg = ["r4"],
+        r5: reg = ["r5"],
+        r6: reg = ["r6"],
+        r7: reg = ["r7"],
+        r8: reg = ["r8"],
+        r9: reg = ["r9"],
+        r10: reg = ["r10"],
+        r12: reg = ["r12"],
+        r13: reg = ["r13"],
+        r14: reg = ["r14"],
+        f0: freg = ["f0"],
+        f1: freg = ["f1"],
+        f2: freg = ["f2"],
+        f3: freg = ["f3"],
+        f4: freg = ["f4"],
+        f5: freg = ["f5"],
+        f6: freg = ["f6"],
+        f7: freg = ["f7"],
+        f8: freg = ["f8"],
+        f9: freg = ["f9"],
+        f10: freg = ["f10"],
+        f11: freg = ["f11"],
+        f12: freg = ["f12"],
+        f13: freg = ["f13"],
+        f14: freg = ["f14"],
+        f15: freg = ["f15"],
+        #error = ["r11"] =>
+            "The frame pointer cannot be used as an operand for inline asm",
+        #error = ["r15"] =>
+            "The stack pointer cannot be used as an operand for inline asm",
+        #error = [
+            "c0", "c1", "c2", "c3",
+            "c4", "c5", "c6", "c7",
+            "c8", "c9", "c10", "c11",
+            "c12", "c13", "c14", "c15"
+        ] =>
+            "control registers are reserved by the kernel and cannot be used as operands for inline asm",
+        #error = [
+            "a0", "a1", "a2", "a3",
+            "a4", "a5", "a6", "a7",
+            "a8", "a9", "a10", "a11",
+            "a12", "a13", "a14", "a15"
+        ] =>
+            "access registers are not supported and cannot be used as operands for inline asm",
+    }
+}
+
+impl S390xInlineAsmReg {
+    pub fn emit(
+        self,
+        out: &mut dyn fmt::Write,
+        _arch: InlineAsmArch,
+        _modifier: Option<char>,
+    ) -> fmt::Result {
+        write!(out, "%{}", self.name())
+    }
+}