Rollup merge of #130895 - RalfJung:asm-tests, r=nnethercote

make type-check-4 asm tests about non-const expressions

These tests recently got changed in https://github.com/rust-lang/rust/pull/129759. I asked the PR author to make the tests read from a `static mut` (rather than just making them "pass"), but I now think that was a mistake: previously the tests failed because the const was not a valid const expression, after the PR they failed because the const failed to evaluate.

So this PR restores the tests to "fail because the const is not a valid const expression". That can be done in a target-independent way so I unified the x86 and aarch64 tests into one.

Cc `@oli-obk` as the original [author](0d88631059) of these tests -- not sure if you still remember what they were intended to test.

tests/ui/asm/aarch64/type-check-4.rs

@@ -1,27 +0,0 @@
-//@ only-aarch64
-//@ build-fail
-
-use std::arch::global_asm;
-
-fn main() {}
-
-// Constants must be... constant
-
-static mut S: i32 = 1;
-const fn const_foo(x: i32) -> i32 {
-    x
-}
-const fn const_bar<T>(x: T) -> T {
-    x
-}
-global_asm!("{}", const unsafe { S });
-//~^ ERROR: evaluation of constant value failed
-//~| mutable global memory
-global_asm!("{}", const const_foo(0));
-global_asm!("{}", const const_foo(unsafe { S }));
-//~^ ERROR: evaluation of constant value failed
-//~| mutable global memory
-global_asm!("{}", const const_bar(0));
-global_asm!("{}", const const_bar(unsafe { S }));
-//~^ ERROR: evaluation of constant value failed
-//~| mutable global memory

tests/ui/asm/aarch64/type-check-4.stderr

@@ -1,21 +0,0 @@
-error[E0080]: evaluation of constant value failed
-  --> $DIR/type-check-4.rs:17:34
-   |
-LL | global_asm!("{}", const unsafe { S });
-   |                                  ^ constant accesses mutable global memory
-
-error[E0080]: evaluation of constant value failed
-  --> $DIR/type-check-4.rs:21:44
-   |
-LL | global_asm!("{}", const const_foo(unsafe { S }));
-   |                                            ^ constant accesses mutable global memory
-
-error[E0080]: evaluation of constant value failed
-  --> $DIR/type-check-4.rs:25:44
-   |
-LL | global_asm!("{}", const const_bar(unsafe { S }));
-   |                                            ^ constant accesses mutable global memory
-
-error: aborting due to 3 previous errors
-
-For more information about this error, try `rustc --explain E0080`.

tests/ui/asm/non-const.rs

@@ -0,0 +1,11 @@
+//@ needs-asm-support
+
+use std::arch::global_asm;
+
+fn main() {}
+
+// Constants must be... constant
+fn non_const_fn(x: i32) -> i32 { x }
+
+global_asm!("/* {} */", const non_const_fn(0));
+//~^ERROR: cannot call non-const fn

tests/ui/asm/non-const.stderr

@@ -0,0 +1,11 @@
+error[E0015]: cannot call non-const fn `non_const_fn` in constants
+  --> $DIR/non-const.rs:10:31
+   |
+LL | global_asm!("/* {} */", const non_const_fn(0));
+   |                               ^^^^^^^^^^^^^^^
+   |
+   = note: calls in constants are limited to constant functions, tuple structs and tuple variants
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0015`.

tests/ui/asm/x86_64/type-check-4.rs

@@ -1,27 +0,0 @@
-//@ only-x86_64
-//@ build-fail
-
-use std::arch::global_asm;
-
-fn main() {}
-
-// Constants must be... constant
-
-static mut S: i32 = 1;
-const fn const_foo(x: i32) -> i32 {
-    x
-}
-const fn const_bar<T>(x: T) -> T {
-    x
-}
-global_asm!("{}", const unsafe { S });
-//~^ ERROR evaluation of constant value failed
-//~| mutable global memory
-global_asm!("{}", const const_foo(0));
-global_asm!("{}", const const_foo(unsafe { S }));
-//~^ ERROR evaluation of constant value failed
-//~| mutable global memory
-global_asm!("{}", const const_bar(0));
-global_asm!("{}", const const_bar(unsafe { S }));
-//~^ ERROR evaluation of constant value failed
-//~| mutable global memory

tests/ui/asm/x86_64/type-check-4.stderr

@@ -1,21 +0,0 @@
-error[E0080]: evaluation of constant value failed
-  --> $DIR/type-check-4.rs:17:34
-   |
-LL | global_asm!("{}", const unsafe { S });
-   |                                  ^ constant accesses mutable global memory
-
-error[E0080]: evaluation of constant value failed
-  --> $DIR/type-check-4.rs:21:44
-   |
-LL | global_asm!("{}", const const_foo(unsafe { S }));
-   |                                            ^ constant accesses mutable global memory
-
-error[E0080]: evaluation of constant value failed
-  --> $DIR/type-check-4.rs:25:44
-   |
-LL | global_asm!("{}", const const_bar(unsafe { S }));
-   |                                            ^ constant accesses mutable global memory
-
-error: aborting due to 3 previous errors
-
-For more information about this error, try `rustc --explain E0080`.