Rollup merge of #100460 - cuviper:drop-llvm-12, r=nagisa

Update the minimum external LLVM to 13

With this change, we'll have stable support for LLVM 13 through 15 (pending release).
For reference, the previous increase to LLVM 12 was #90175.

r? `@nagisa`

6 files changed, 26 insertions, 103 deletions

diff --git a/compiler/rustc_codegen_llvm/src/asm.rs b/compiler/rustc_codegen_llvm/src/asm.rs
index a53946995ee..2a6612eb86f 100644
--- a/compiler/rustc_codegen_llvm/src/asm.rs
+++ b/compiler/rustc_codegen_llvm/src/asm.rs
@@ -3,7 +3,6 @@ use crate::builder::Builder;
 use crate::common::Funclet;
 use crate::context::CodegenCx;
 use crate::llvm;
-use crate::llvm_util;
 use crate::type_::Type;
 use crate::type_of::LayoutLlvmExt;
 use crate::value::Value;
@@ -419,13 +418,6 @@ pub(crate) fn inline_asm_call<'ll>(
         let constraints_ok = llvm::LLVMRustInlineAsmVerify(fty, cons.as_ptr().cast(), cons.len());
         debug!("constraint verification result: {:?}", constraints_ok);
         if constraints_ok {
-            if unwind && llvm_util::get_version() < (13, 0, 0) {
-                bx.cx.sess().span_fatal(
-                    line_spans[0],
-                    "unwinding from inline assembly is only supported on llvm >= 13.",
-                );
-            }
-
             let v = llvm::LLVMRustInlineAsm(
                 fty,
                 asm.as_ptr().cast(),
diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 0913715b3c0..740a68d0772 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -5,7 +5,7 @@ use crate::back::profiling::{
 use crate::base;
 use crate::common;
 use crate::consts;
-use crate::llvm::{self, DiagnosticInfo, PassManager, SMDiagnostic};
+use crate::llvm::{self, DiagnosticInfo, PassManager};
 use crate::llvm_util;
 use crate::type_::Type;
 use crate::LlvmCodegenBackend;
@@ -304,7 +304,6 @@ impl<'a> DiagnosticHandlers<'a> {
                 remark_passes.as_ptr(),
                 remark_passes.len(),
             );
-            llvm::LLVMRustSetInlineAsmDiagnosticHandler(llcx, inline_asm_handler, data.cast());
             DiagnosticHandlers { data, llcx, old_handler }
         }
     }
@@ -312,9 +311,7 @@ impl<'a> DiagnosticHandlers<'a> {
 
 impl<'a> Drop for DiagnosticHandlers<'a> {
     fn drop(&mut self) {
-        use std::ptr::null_mut;
         unsafe {
-            llvm::LLVMRustSetInlineAsmDiagnosticHandler(self.llcx, inline_asm_handler, null_mut());
             llvm::LLVMRustContextSetDiagnosticHandler(self.llcx, self.old_handler);
             drop(Box::from_raw(self.data));
         }
@@ -342,16 +339,6 @@ fn report_inline_asm(
     cgcx.diag_emitter.inline_asm_error(cookie as u32, msg, level, source);
 }
 
-unsafe extern "C" fn inline_asm_handler(diag: &SMDiagnostic, user: *const c_void, cookie: c_uint) {
-    if user.is_null() {
-        return;
-    }
-    let (cgcx, _) = *(user as *const (&CodegenContext<LlvmCodegenBackend>, &Handler));
-
-    let smdiag = llvm::diagnostic::SrcMgrDiagnostic::unpack(diag);
-    report_inline_asm(cgcx, smdiag.message, smdiag.level, cookie, smdiag.source);
-}
-
 unsafe extern "C" fn diagnostic_handler(info: &DiagnosticInfo, user: *mut c_void) {
     if user.is_null() {
         return;
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index d3096c73a8a..073feecb164 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -3,7 +3,6 @@ use crate::common::Funclet;
 use crate::context::CodegenCx;
 use crate::llvm::{self, BasicBlock, False};
 use crate::llvm::{AtomicOrdering, AtomicRmwBinOp, SynchronizationScope};
-use crate::llvm_util;
 use crate::type_::Type;
 use crate::type_of::LayoutLlvmExt;
 use crate::value::Value;
@@ -1038,25 +1037,11 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         dst: &'ll Value,
         cmp: &'ll Value,
         src: &'ll Value,
-        mut order: rustc_codegen_ssa::common::AtomicOrdering,
+        order: rustc_codegen_ssa::common::AtomicOrdering,
         failure_order: rustc_codegen_ssa::common::AtomicOrdering,
         weak: bool,
     ) -> &'ll Value {
         let weak = if weak { llvm::True } else { llvm::False };
-        if llvm_util::get_version() < (13, 0, 0) {
-            use rustc_codegen_ssa::common::AtomicOrdering::*;
-            // Older llvm has the pre-C++17 restriction on
-            // success and failure memory ordering,
-            // requiring the former to be at least as strong as the latter.
-            // So, for llvm 12, we upgrade the success ordering to a stronger
-            // one if necessary.
-            match (order, failure_order) {
-                (Relaxed, Acquire) => order = Acquire,
-                (Release, Acquire) => order = AcquireRelease,
-                (_, SequentiallyConsistent) => order = SequentiallyConsistent,
-                _ => {}
-            }
-        }
         unsafe {
             llvm::LLVMRustBuildAtomicCmpXchg(
                 self.llbuilder,
@@ -1444,51 +1429,37 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
         }
     }
 
-    fn fptoint_sat_broken_in_llvm(&self) -> bool {
-        match self.tcx.sess.target.arch.as_ref() {
-            // FIXME - https://bugs.llvm.org/show_bug.cgi?id=50083
-            "riscv64" => llvm_util::get_version() < (13, 0, 0),
-            _ => false,
-        }
-    }
-
     fn fptoint_sat(
         &mut self,
         signed: bool,
         val: &'ll Value,
         dest_ty: &'ll Type,
     ) -> Option<&'ll Value> {
-        if !self.fptoint_sat_broken_in_llvm() {
-            let src_ty = self.cx.val_ty(val);
-            let (float_ty, int_ty, vector_length) = if self.cx.type_kind(src_ty) == TypeKind::Vector
-            {
-                assert_eq!(self.cx.vector_length(src_ty), self.cx.vector_length(dest_ty));
-                (
-                    self.cx.element_type(src_ty),
-                    self.cx.element_type(dest_ty),
-                    Some(self.cx.vector_length(src_ty)),
-                )
-            } else {
-                (src_ty, dest_ty, None)
-            };
-            let float_width = self.cx.float_width(float_ty);
-            let int_width = self.cx.int_width(int_ty);
-
-            let instr = if signed { "fptosi" } else { "fptoui" };
-            let name = if let Some(vector_length) = vector_length {
-                format!(
-                    "llvm.{}.sat.v{}i{}.v{}f{}",
-                    instr, vector_length, int_width, vector_length, float_width
-                )
-            } else {
-                format!("llvm.{}.sat.i{}.f{}", instr, int_width, float_width)
-            };
-            let f =
-                self.declare_cfn(&name, llvm::UnnamedAddr::No, self.type_func(&[src_ty], dest_ty));
-            Some(self.call(self.type_func(&[src_ty], dest_ty), f, &[val], None))
+        let src_ty = self.cx.val_ty(val);
+        let (float_ty, int_ty, vector_length) = if self.cx.type_kind(src_ty) == TypeKind::Vector {
+            assert_eq!(self.cx.vector_length(src_ty), self.cx.vector_length(dest_ty));
+            (
+                self.cx.element_type(src_ty),
+                self.cx.element_type(dest_ty),
+                Some(self.cx.vector_length(src_ty)),
+            )
         } else {
-            None
-        }
+            (src_ty, dest_ty, None)
+        };
+        let float_width = self.cx.float_width(float_ty);
+        let int_width = self.cx.int_width(int_ty);
+
+        let instr = if signed { "fptosi" } else { "fptoui" };
+        let name = if let Some(vector_length) = vector_length {
+            format!(
+                "llvm.{}.sat.v{}i{}.v{}f{}",
+                instr, vector_length, int_width, vector_length, float_width
+            )
+        } else {
+            format!("llvm.{}.sat.i{}.f{}", instr, int_width, float_width)
+        };
+        let f = self.declare_cfn(&name, llvm::UnnamedAddr::No, self.type_func(&[src_ty], dest_ty));
+        Some(self.call(self.type_func(&[src_ty], dest_ty), f, &[val], None))
     }
 
     pub(crate) fn landing_pad(
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs
index 5857b83f6c9..d4d84147239 100644
--- a/compiler/rustc_codegen_llvm/src/context.rs
+++ b/compiler/rustc_codegen_llvm/src/context.rs
@@ -142,17 +142,6 @@ pub unsafe fn create_module<'ll>(
 
     let mut target_data_layout = sess.target.data_layout.to_string();
     let llvm_version = llvm_util::get_version();
-    if llvm_version < (13, 0, 0) {
-        if sess.target.arch == "powerpc64" {
-            target_data_layout = target_data_layout.replace("-S128", "");
-        }
-        if sess.target.arch == "wasm32" {
-            target_data_layout = "e-m:e-p:32:32-i64:64-n32:64-S128".to_string();
-        }
-        if sess.target.arch == "wasm64" {
-            target_data_layout = "e-m:e-p:64:64-i64:64-n32:64-S128".to_string();
-        }
-    }
     if llvm_version < (14, 0, 0) {
         if sess.target.llvm_target == "i686-pc-windows-msvc"
             || sess.target.llvm_target == "i586-pc-windows-msvc"
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index d676ea35090..4ca3dd78cae 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -2424,12 +2424,6 @@ extern "C" {
         cookie_out: &mut c_uint,
     ) -> &'a SMDiagnostic;
 
-    pub fn LLVMRustSetInlineAsmDiagnosticHandler(
-        C: &Context,
-        H: InlineAsmDiagHandlerTy,
-        CX: *mut c_void,
-    );
-
     #[allow(improper_ctypes)]
     pub fn LLVMRustUnpackSMDiagnostic(
         d: &SMDiagnostic,
diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs
index 96d238eda59..f5d676c44e3 100644
--- a/compiler/rustc_codegen_llvm/src/llvm_util.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs
@@ -92,16 +92,6 @@ unsafe fn configure_llvm(sess: &Session) {
             add("-generate-arange-section", false);
         }
 
-        // Disable the machine outliner by default in LLVM versions 11 and LLVM
-        // version 12, where it leads to miscompilation.
-        //
-        // Ref:
-        // - https://github.com/rust-lang/rust/issues/85351
-        // - https://reviews.llvm.org/D103167
-        if llvm_util::get_version() < (13, 0, 0) {
-            add("-enable-machine-outliner=never", false);
-        }
-
         match sess.opts.unstable_opts.merge_functions.unwrap_or(sess.target.merge_functions) {
             MergeFunctions::Disabled | MergeFunctions::Trampolines => {}
             MergeFunctions::Aliases => {