Rollup merge of #103110 - RalfJung:manual-send, r=thomcc

[rust.git] / compiler / rustc_codegen_ssa / src / mir / block.rs

diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs
index e7abae665e357b3712effd43fd94bd7394c9d78a..29b7c9b0a8832af029fd84c07812acc057143d9f 100644 (file)
--- a/compiler/rustc_codegen_ssa/src/mir/block.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/block.rs
@@ -63,7 +63,9 @@ fn funclet<'b, Bx: BuilderMethods<'a, 'tcx>>(
         }
     }
 
-    fn lltarget<Bx: BuilderMethods<'a, 'tcx>>(
+    /// Get a basic block (creating it if necessary), possibly with a landing
+    /// pad next to it.
+    fn llbb_with_landing_pad<Bx: BuilderMethods<'a, 'tcx>>(
         &self,
         fx: &mut FunctionCx<'a, 'tcx, Bx>,
         target: mir::BasicBlock,
@@ -73,27 +75,31 @@ fn lltarget<Bx: BuilderMethods<'a, 'tcx>>(
         let target_funclet = fx.cleanup_kinds[target].funclet_bb(target);
         match (self.funclet_bb, target_funclet) {
             (None, None) => (lltarget, false),
-            (Some(f), Some(t_f)) if f == t_f || !base::wants_msvc_seh(fx.cx.tcx().sess) => {
-                (lltarget, false)
-            }
             // jump *into* cleanup - need a landing pad if GNU, cleanup pad if MSVC
             (None, Some(_)) => (fx.landing_pad_for(target), false),
             (Some(_), None) => span_bug!(span, "{:?} - jump out of cleanup?", self.terminator),
-            (Some(_), Some(_)) => (fx.landing_pad_for(target), true),
+            (Some(f), Some(t_f)) => {
+                if f == t_f || !base::wants_msvc_seh(fx.cx.tcx().sess) {
+                    (lltarget, false)
+                } else {
+                    (fx.landing_pad_for(target), true)
+                }
+            }
         }
     }
 
-    /// Create a basic block.
-    fn llblock<Bx: BuilderMethods<'a, 'tcx>>(
+    /// Get a basic block (creating it if necessary), possibly with cleanup
+    /// stuff in it or next to it.
+    fn llbb_with_cleanup<Bx: BuilderMethods<'a, 'tcx>>(
         &self,
         fx: &mut FunctionCx<'a, 'tcx, Bx>,
         target: mir::BasicBlock,
     ) -> Bx::BasicBlock {
-        let (lltarget, is_cleanupret) = self.lltarget(fx, target);
+        let (lltarget, is_cleanupret) = self.llbb_with_landing_pad(fx, target);
         if is_cleanupret {
             // MSVC cross-funclet jump - need a trampoline
-
-            debug!("llblock: creating cleanup trampoline for {:?}", target);
+            debug_assert!(base::wants_msvc_seh(fx.cx.tcx().sess));
+            debug!("llbb_with_cleanup: creating cleanup trampoline for {:?}", target);
             let name = &format!("{:?}_cleanup_trampoline_{:?}", self.bb, target);
             let trampoline_llbb = Bx::append_block(fx.cx, fx.llfn, name);
             let mut trampoline_bx = Bx::build(fx.cx, trampoline_llbb);
@@ -110,10 +116,11 @@ fn funclet_br<Bx: BuilderMethods<'a, 'tcx>>(
         bx: &mut Bx,
         target: mir::BasicBlock,
     ) {
-        let (lltarget, is_cleanupret) = self.lltarget(fx, target);
+        let (lltarget, is_cleanupret) = self.llbb_with_landing_pad(fx, target);
         if is_cleanupret {
-            // micro-optimization: generate a `ret` rather than a jump
+            // MSVC micro-optimization: generate a `ret` rather than a jump
             // to a trampoline.
+            debug_assert!(base::wants_msvc_seh(fx.cx.tcx().sess));
             bx.cleanup_ret(self.funclet(fx).unwrap(), Some(lltarget));
         } else {
             bx.br(lltarget);
@@ -138,7 +145,7 @@ fn do_call<Bx: BuilderMethods<'a, 'tcx>>(
         let fn_ty = bx.fn_decl_backend_type(&fn_abi);
 
         let unwind_block = if let Some(cleanup) = cleanup.filter(|_| fn_abi.can_unwind) {
-            Some(self.llblock(fx, cleanup))
+            Some(self.llbb_with_cleanup(fx, cleanup))
         } else if fx.mir[self.bb].is_cleanup
             && fn_abi.can_unwind
             && !base::wants_msvc_seh(fx.cx.tcx().sess)
@@ -231,7 +238,7 @@ fn do_inlineasm<Bx: BuilderMethods<'a, 'tcx>>(
                 options,
                 line_spans,
                 instance,
-                Some((ret_llbb, self.llblock(fx, cleanup), self.funclet(fx))),
+                Some((ret_llbb, self.llbb_with_cleanup(fx, cleanup), self.funclet(fx))),
             );
         } else {
             bx.codegen_inline_asm(template, &operands, options, line_spans, instance, None);
@@ -281,8 +288,8 @@ fn codegen_switchint_terminator(
         if target_iter.len() == 1 {
             // If there are two targets (one conditional, one fallback), emit br instead of switch
             let (test_value, target) = target_iter.next().unwrap();
-            let lltrue = helper.llblock(self, target);
-            let llfalse = helper.llblock(self, targets.otherwise());
+            let lltrue = helper.llbb_with_cleanup(self, target);
+            let llfalse = helper.llbb_with_cleanup(self, targets.otherwise());
             if switch_ty == bx.tcx().types.bool {
                 // Don't generate trivial icmps when switching on bool
                 match test_value {
@@ -299,8 +306,8 @@ fn codegen_switchint_terminator(
         } else {
             bx.switch(
                 discr.immediate(),
-                helper.llblock(self, targets.otherwise()),
-                target_iter.map(|(value, target)| (value, helper.llblock(self, target))),
+                helper.llbb_with_cleanup(self, targets.otherwise()),
+                target_iter.map(|(value, target)| (value, helper.llbb_with_cleanup(self, target))),
             );
         }
     }
@@ -530,7 +537,7 @@ fn codegen_assert_terminator(
         let cond = bx.expect(cond, expected);
 
         // Create the failure block and the conditional branch to it.
-        let lltarget = helper.llblock(self, target);
+        let lltarget = helper.llbb_with_cleanup(self, target);
         let panic_block = bx.append_sibling_block("panic");
         if expected {
             bx.cond_br(cond, lltarget, panic_block);