Rollup merge of #69437 - RalfJung:miri-no-codegen, r=ecstatic-morse

Dylan-DPC · web-flow · commit e238eb610f36 · 2020-02-24T20:10:19.000+01:00
no more codegen for miri_start_panic With rust-lang/miri#1136 landed, we don't generate code any more for crates that will be run by Miri. So the LLVM backend does not have to implement the `miri_start_panic` intrinsic any more. Cc @Aaron1011
diff --git a/src/librustc_codegen_ssa/mir/block.rs b/src/librustc_codegen_ssa/mir/block.rs
@@ -515,12 +515,9 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             return;
         }
 
-        // For normal codegen, this Miri-specific intrinsic is just a NOP.
+        // For normal codegen, this Miri-specific intrinsic should never occur.
         if intrinsic == Some("miri_start_panic") {
-            let target = destination.as_ref().unwrap().1;
-            helper.maybe_sideeffect(self.mir, &mut bx, &[target]);
-            helper.funclet_br(self, &mut bx, target);
-            return;
+            bug!("`miri_start_panic` should never end up in compiled code");
         }
 
         // Emit a panic or a no-op for `panic_if_uninhabited`.

Original file line number	Diff line number	Diff line change
`@@ -515,12 +515,9 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {`
`515`	`515`	`return;`
`516`	`516`	`}`
`517`	`517`
`518`		`- // For normal codegen, this Miri-specific intrinsic is just a NOP.`
	`518`	`+ // For normal codegen, this Miri-specific intrinsic should never occur.`
`519`	`519`	`if intrinsic == Some("miri_start_panic") {`
`520`		`- let target = destination.as_ref().unwrap().1;`
`521`		`- helper.maybe_sideeffect(self.mir, &mut bx, &[target]);`
`522`		`- helper.funclet_br(self, &mut bx, target);`
`523`		`- return;`
	`520`	+ bug!("`miri_start_panic` should never end up in compiled code");
`524`	`521`	`}`
`525`	`522`
`526`	`523`	// Emit a panic or a no-op for `panic_if_uninhabited`.