Enable Xtensa codegen for rustc_codegen_gcc

* Updates uses of object::Architecture within the compiler

Author: MabezDev

compiler/rustc_codegen_gcc/src/asm.rs

@@ -717,6 +717,9 @@ fn reg_class_to_gcc(reg_class: InlineAsmRegClass) -> &'static str {
             | X86InlineAsmRegClass::mmx_reg
             | X86InlineAsmRegClass::tmm_reg,
         ) => unreachable!("clobber-only"),
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::reg) => "r",
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::freg) => "f",
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::breg) => "b",
         InlineAsmRegClass::SpirV(SpirVInlineAsmRegClass::reg) => {
             bug!("GCC backend does not support SPIR-V")
         }
@@ -822,7 +825,10 @@ fn dummy_output_type<'gcc, 'tcx>(cx: &CodegenCx<'gcc, 'tcx>, reg: InlineAsmRegCl
         InlineAsmRegClass::CSKY(CSKYInlineAsmRegClass::freg) => cx.type_f32(),
         InlineAsmRegClass::SpirV(SpirVInlineAsmRegClass::reg) => {
             bug!("GCC backend does not support SPIR-V")
-        }
+        },
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::reg) => cx.type_i32(),
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::freg) => cx.type_f32(),
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::breg) => cx.type_i8(), // FIXME: should this be i1?
         InlineAsmRegClass::Err => unreachable!(),
     }
 }
@@ -1006,7 +1012,10 @@ fn modifier_to_gcc(
         InlineAsmRegClass::CSKY(_) => None,
         InlineAsmRegClass::SpirV(SpirVInlineAsmRegClass::reg) => {
             bug!("LLVM backend does not support SPIR-V")
-        }
+        },
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::reg) => unimplemented!(),
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::freg) => unimplemented!(),
+        InlineAsmRegClass::Xtensa(XtensaInlineAsmRegClass::breg) => unimplemented!(),
         InlineAsmRegClass::Err => unreachable!(),
     }
 }

compiler/rustc_target/src/spec/mod.rs

@@ -3605,6 +3605,7 @@ impl Target {
             "avr" => (Architecture::Avr, None),
             "msp430" => (Architecture::Msp430, None),
             "hexagon" => (Architecture::Hexagon, None),
+            "xtensa" => (Architecture::Xtensa, None),
             "bpf" => (Architecture::Bpf, None),
             "loongarch64" => (Architecture::LoongArch64, None),
             "csky" => (Architecture::Csky, None),