Rollup merge of #158899 - scottmcm:better-volatile-store, r=saethlin

Fix `unaligned_volatile_store` by removing `MemFlags::UNALIGNED`

Fixes rust-lang/rust#158897

There seems to be no reason to have this flag at all, as anything that wants it should just adjust the https://doc.rust-lang.org/nightly/nightly-rustc/rustc_codegen_ssa/mir/place/struct.PlaceValue.html#structfield.align instead.

r? codegen

Author: jhpratt

src/builder.rs

@@ -1155,7 +1155,7 @@ impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
         // NOTE: libgccjit does not support specifying the alignment on the assignment, so we cast
         // to type so it gets the proper alignment.
         let destination_type = destination.to_rvalue().get_type().unqualified();
-        let align = if flags.contains(MemFlags::UNALIGNED) { 1 } else { align.bytes() };
+        let align = align.bytes();
         let mut modified_destination_type = destination_type.get_aligned(align);
         if flags.contains(MemFlags::VOLATILE) {
             modified_destination_type = modified_destination_type.make_volatile();

src/intrinsic/mod.rs

@@ -377,16 +377,6 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
                     load
                 }
             }
-            sym::volatile_store => {
-                let dst = args[0].deref(self.cx());
-                args[1].val.volatile_store(self, dst);
-                return IntrinsicResult::WroteIntoPlace;
-            }
-            sym::unaligned_volatile_store => {
-                let dst = args[0].deref(self.cx());
-                args[1].val.unaligned_volatile_store(self, dst);
-                return IntrinsicResult::WroteIntoPlace;
-            }
             sym::prefetch_read_data
             | sym::prefetch_write_data
             | sym::prefetch_read_instruction