[RISCV] Remove support for attribute interrupt("user").

This was part of the N extension which didn't make it version
1.12 of the privilege specification.

Reviewed By: kito-cheng

Differential Revision: https://reviews.llvm.org/D149314

Author: topperc

clang/include/clang/Basic/Attr.td

@@ -1864,8 +1864,8 @@ def RISCVInterrupt : InheritableAttr, TargetSpecificAttr<TargetRISCV> {
   let Spellings = [GCC<"interrupt">];
   let Subjects = SubjectList<[Function]>;
   let Args = [EnumArgument<"Interrupt", "InterruptType",
-                           ["user", "supervisor", "machine"],
-                           ["user", "supervisor", "machine"],
+                           ["supervisor", "machine"],
+                           ["supervisor", "machine"],
                            1>];
   let ParseKind = "Interrupt";
   let Documentation = [RISCVInterruptDocs];

clang/lib/CodeGen/TargetInfo.cpp

@@ -11524,7 +11524,6 @@ class RISCVTargetCodeGenInfo : public TargetCodeGenInfo {
 
     const char *Kind;
     switch (Attr->getInterrupt()) {
-    case RISCVInterruptAttr::user: Kind = "user"; break;
     case RISCVInterruptAttr::supervisor: Kind = "supervisor"; break;
     case RISCVInterruptAttr::machine: Kind = "machine"; break;
     }

clang/test/Sema/riscv-interrupt-attr.c

@@ -4,35 +4,32 @@
 // RUN: %clang_cc1 %s -triple riscv64-unknown-elf -verify -fsyntax-only
 
 #if defined(CHECK_IR)
-// CHECK-LABEL:  @foo_user() #0
-// CHECK: ret void
-__attribute__((interrupt("user"))) void foo_user(void) {}
-// CHECK-LABEL:  @foo_supervisor() #1
+// CHECK-LABEL:  @foo_supervisor() #0
 // CHECK: ret void
 __attribute__((interrupt("supervisor"))) void foo_supervisor(void) {}
-// CHECK-LABEL:  @foo_machine() #2
+// CHECK-LABEL:  @foo_machine() #1
 // CHECK: ret void
 __attribute__((interrupt("machine"))) void foo_machine(void) {}
-// CHECK-LABEL:  @foo_default() #2
+// CHECK-LABEL:  @foo_default() #1
 // CHECK: ret void
 __attribute__((interrupt())) void foo_default(void) {}
-// CHECK-LABEL:  @foo_default2() #2
+// CHECK-LABEL:  @foo_default2() #1
 // CHECK: ret void
 __attribute__((interrupt())) void foo_default2(void) {}
 // CHECK: attributes #0
-// CHECK: "interrupt"="user"
-// CHECK: attributes #1
 // CHECK: "interrupt"="supervisor"
-// CHECK: attributes #2
+// CHECK: attributes #1
 // CHECK: "interrupt"="machine"
 #else
 struct a { int b; };
 
 struct a test __attribute__((interrupt)); // expected-warning {{'interrupt' attribute only applies to functions}}
 
 __attribute__((interrupt("USER"))) void foo1(void) {} // expected-warning {{'interrupt' attribute argument not supported: USER}}
+__attribute__((interrupt("user"))) void foo1b(void) {} // expected-warning {{'interrupt' attribute argument not supported: user}}
+__attribute__((interrupt("MACHINE"))) void foo1c(void) {} // expected-warning {{'interrupt' attribute argument not supported: MACHINE}}
 
-__attribute__((interrupt("user", 1))) void foo2(void) {} // expected-error {{'interrupt' attribute takes no more than 1 argument}}
+__attribute__((interrupt("machine", 1))) void foo2(void) {} // expected-error {{'interrupt' attribute takes no more than 1 argument}}
 
 __attribute__((interrupt)) int foo3(void) {return 0;} // expected-warning {{RISC-V 'interrupt' attribute only applies to functions that have a 'void' return type}}
 
@@ -41,19 +38,17 @@ __attribute__((interrupt())) void foo4(void) {}
 
 __attribute__((interrupt())) void foo5(int a) {} // expected-warning {{RISC-V 'interrupt' attribute only applies to functions that have no parameters}}
 
-__attribute__((interrupt("user"), interrupt("supervisor"))) void foo6(void) {} // expected-warning {{repeated RISC-V 'interrupt' attribute}} \
+__attribute__((interrupt("machine"), interrupt("supervisor"))) void foo6(void) {} // expected-warning {{repeated RISC-V 'interrupt' attribute}} \
   // expected-note {{repeated RISC-V 'interrupt' attribute is here}}
 
 __attribute__((interrupt, interrupt)) void foo7(void) {} // expected-warning {{repeated RISC-V 'interrupt' attribute}} \
                                                      // expected-note {{repeated RISC-V 'interrupt' attribute is here}}
 
 __attribute__((interrupt(""))) void foo8(void) {} // expected-warning {{'interrupt' attribute argument not supported}}
 
-__attribute__((interrupt("user"))) void foo9(void);
 __attribute__((interrupt("supervisor"))) void foo9(void);
 __attribute__((interrupt("machine"))) void foo9(void);
 
-__attribute__((interrupt("user"))) void foo10(void) {}
 __attribute__((interrupt("supervisor"))) void foo11(void) {}
 __attribute__((interrupt("machine"))) void foo12(void) {}
 __attribute__((interrupt())) void foo13(void) {}