Rollup merge of #65664 - anp:panic-location, r=eddyb

`std::panic::Location` is a lang_item, add `core::intrinsics::caller_location` (RFC 2091 3/N)

[Tracking issue](https://github.com/rust-lang/rust/issues/47809)
[RFC text](https://github.com/rust-lang/rfcs/blob/master/text/2091-inline-semantic.md)

@eddyb suggested doing this intrinsic implementation ahead of actually implementing the `#[track_caller]` attribute so that there's an easily tested intermediate step between adding the shim and wiring up the attribute.

2 files changed, 7 insertions, 49 deletions

diff --git a/src/librustc_codegen_llvm/builder.rs b/src/librustc_codegen_llvm/builder.rs
index 98be0ae4433..312c41b88b0 100644
--- a/src/librustc_codegen_llvm/builder.rs
+++ b/src/librustc_codegen_llvm/builder.rs
@@ -23,7 +23,6 @@ use std::ffi::CStr;
 use std::ops::{Deref, Range};
 use std::ptr;
 use std::iter::TrustedLen;
-use syntax::symbol::Symbol;
 
 // All Builders must have an llfn associated with them
 #[must_use]
@@ -1067,36 +1066,6 @@ impl StaticBuilderMethods for Builder<'a, 'll, 'tcx> {
         // Forward to the `get_static` method of `CodegenCx`
         self.cx().get_static(def_id)
     }
-
-    fn static_panic_msg(
-        &mut self,
-        msg: Option<Symbol>,
-        filename: Symbol,
-        line: Self::Value,
-        col: Self::Value,
-        kind: &str,
-    ) -> Self::Value {
-        let align = self.tcx.data_layout.aggregate_align.abi
-            .max(self.tcx.data_layout.i32_align.abi)
-            .max(self.tcx.data_layout.pointer_align.abi);
-
-        let filename = self.const_str_slice(filename);
-
-        let with_msg_components;
-        let without_msg_components;
-
-        let components = if let Some(msg) = msg {
-            let msg = self.const_str_slice(msg);
-            with_msg_components = [msg, filename, line, col];
-            &with_msg_components as &[_]
-        } else {
-            without_msg_components = [filename, line, col];
-            &without_msg_components as &[_]
-        };
-
-        let struct_ = self.const_struct(&components, false);
-        self.static_addr_of(struct_, align, Some(kind))
-    }
 }
 
 impl Builder<'a, 'll, 'tcx> {
diff --git a/src/librustc_codegen_llvm/common.rs b/src/librustc_codegen_llvm/common.rs
index a1a5232d588..f38f9dfecd3 100644
--- a/src/librustc_codegen_llvm/common.rs
+++ b/src/librustc_codegen_llvm/common.rs
@@ -3,7 +3,6 @@
 //! Code that is useful in various codegen modules.
 
 use crate::llvm::{self, True, False, Bool, BasicBlock, OperandBundleDef, ConstantInt};
-use crate::abi;
 use crate::consts;
 use crate::type_::Type;
 use crate::type_of::LayoutLlvmExt;
@@ -96,16 +95,6 @@ impl BackendTypes for CodegenCx<'ll, 'tcx> {
 }
 
 impl CodegenCx<'ll, 'tcx> {
-    pub fn const_fat_ptr(
-        &self,
-        ptr: &'ll Value,
-        meta: &'ll Value
-    ) -> &'ll Value {
-        assert_eq!(abi::FAT_PTR_ADDR, 0);
-        assert_eq!(abi::FAT_PTR_EXTRA, 1);
-        self.const_struct(&[ptr, meta], false)
-    }
-
     pub fn const_array(&self, ty: &'ll Type, elts: &[&'ll Value]) -> &'ll Value {
         unsafe {
             return llvm::LLVMConstArray(ty, elts.as_ptr(), elts.len() as c_uint);
@@ -150,13 +139,6 @@ impl CodegenCx<'ll, 'tcx> {
         }
     }
 
-    pub fn const_str_slice(&self, s: Symbol) -> &'ll Value {
-        let len = s.as_str().len();
-        let cs = consts::ptrcast(self.const_cstr(s, false),
-            self.type_ptr_to(self.layout_of(self.tcx.mk_str()).llvm_type(self)));
-        self.const_fat_ptr(cs, self.const_usize(len as u64))
-    }
-
     pub fn const_get_elt(&self, v: &'ll Value, idx: u64) -> &'ll Value {
         unsafe {
             assert_eq!(idx as c_uint as u64, idx);
@@ -237,6 +219,13 @@ impl ConstMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         unsafe { llvm::LLVMConstReal(t, val) }
     }
 
+    fn const_str(&self, s: Symbol) -> (&'ll Value, &'ll Value) {
+        let len = s.as_str().len();
+        let cs = consts::ptrcast(self.const_cstr(s, false),
+            self.type_ptr_to(self.layout_of(self.tcx.mk_str()).llvm_type(self)));
+        (cs, self.const_usize(len as u64))
+    }
+
     fn const_struct(
         &self,
         elts: &[&'ll Value],