New upstream version 1.12.0+dfsg1

[rustc.git] / src / librustc_trans / adt.rs

diff --git a/src/librustc_trans/adt.rs b/src/librustc_trans/adt.rs
index 23c4258caf7bd9c5ca873ba44d9c4ac28880f2d0..5a88385a4635e22738ddb277e238deea14da7745 100644 (file)
--- a/src/librustc_trans/adt.rs
+++ b/src/librustc_trans/adt.rs
@@ -55,7 +55,7 @@ use syntax::attr;
 use syntax::attr::IntType;
 use _match;
 use abi::FAT_PTR_ADDR;
-use base::InitAlloca;
+use base::{self, InitAlloca};
 use build::*;
 use cleanup;
 use cleanup::CleanupMethods;
@@ -1023,16 +1023,32 @@ pub fn trans_set_discr<'blk, 'tcx>(bcx: Block<'blk, 'tcx>, r: &Repr<'tcx>,
                 Store(bcx, C_null(llptrty), val);
             }
         }
-        StructWrappedNullablePointer { nndiscr, ref discrfield, .. } => {
+        StructWrappedNullablePointer { nndiscr, ref discrfield, ref nonnull, .. } => {
             if discr != nndiscr {
-                let llptrptr = GEPi(bcx, val, &discrfield[..]);
-                let llptrty = val_ty(llptrptr).element_type();
-                Store(bcx, C_null(llptrty), llptrptr);
+                if target_sets_discr_via_memset(bcx) {
+                    // Issue #34427: As workaround for LLVM bug on
+                    // ARM, use memset of 0 on whole struct rather
+                    // than storing null to single target field.
+                    let b = B(bcx);
+                    let llptr = b.pointercast(val, Type::i8(b.ccx).ptr_to());
+                    let fill_byte = C_u8(b.ccx, 0);
+                    let size = C_uint(b.ccx, nonnull.size);
+                    let align = C_i32(b.ccx, nonnull.align as i32);
+                    base::call_memset(&b, llptr, fill_byte, size, align, false);
+                } else {
+                    let llptrptr = GEPi(bcx, val, &discrfield[..]);
+                    let llptrty = val_ty(llptrptr).element_type();
+                    Store(bcx, C_null(llptrty), llptrptr);
+                }
             }
         }
     }
 }
 
+fn target_sets_discr_via_memset<'blk, 'tcx>(bcx: Block<'blk, 'tcx>) -> bool {
+    bcx.sess().target.target.arch == "arm" || bcx.sess().target.target.arch == "aarch64"
+}
+
 fn assert_discr_in_range(ity: IntType, min: Disr, max: Disr, discr: Disr) {
     match ity {
         attr::UnsignedInt(_) => {