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// GVN may create indirect constants with higher alignment than their type requires. Verify that we
// do not ICE during codegen, and that the LLVM constant has the higher alignment.
//
//@ compile-flags: -Zmir-opt-level=0 -Zmir-enable-passes=+GVN
//@ compile-flags: -Cno-prepopulate-passes --crate-type=lib
//@ only-64bit
struct S(i32);
struct SmallStruct(f32, Option<S>, &'static [f32]);
// CHECK: @0 = private unnamed_addr constant
// CHECK-SAME: , align 8
#[no_mangle]
pub fn overaligned_constant() {
// CHECK-LABEL: @overaligned_constant
// CHECK: [[full:%_.*]] = alloca [32 x i8], align 8
// CHECK: call void @llvm.memcpy.p0.p0.i64(ptr align 8 [[full]], ptr align 8 @0, i64 32, i1 false)
// CHECK: %b.0 = load i32, ptr @0, align 4
// CHECK: %b.1 = load i32, ptr getelementptr inbounds ({{.*}}), align 4
let mut s = S(1);
s.0 = 3;
// SMALL_VAL corresponds to a MIR allocation with alignment 8.
const SMALL_VAL: SmallStruct = SmallStruct(4., Some(S(1)), &[]);
// In pre-codegen MIR:
// `a` is a scalar 4.
// `b` is an indirect constant at `SMALL_VAL`'s alloc with 0 offset.
// `c` is the empty slice.
//
// As a consequence, during codegen, we create a LLVM allocation for `SMALL_VAL`, with
// alignment 8, but only use the `Option<S>` field, at offset 0 with alignment 4.
let SmallStruct(a, b, c) = SMALL_VAL;
}
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