Use assume operand bundles for assume_nonnull.

Author: scottmcm

compiler/rustc_codegen_llvm/src/builder.rs

@@ -782,6 +782,26 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         *self = Self::build(self.cx, next_bb);
     }
 
+    fn assume_nonnull(&mut self, val: Self::Value) {
+        let (ty, f) = self.cx.get_intrinsic("llvm.assume".into(), &[]);
+        let const_true = self.cx.const_bool(true);
+        let meta = llvm::OperandBundleBox::new("nonnull", &[val]);
+        let args = [const_true];
+        let bundles = [meta.as_ref()];
+        unsafe {
+            llvm::LLVMBuildCallWithOperandBundles(
+                self.llbuilder,
+                ty,
+                f,
+                args.as_ptr(),
+                1,
+                bundles.as_ptr(),
+                1,
+                c"".as_ptr(),
+            );
+        }
+    }
+
     fn range_metadata(&mut self, load: &'ll Value, range: WrappingRange) {
         if self.cx.sess().opts.optimize == OptLevel::No {
             // Don't emit metadata we're not going to use

tests/codegen-llvm/intrinsics/transmute-niched.rs

@@ -193,8 +193,7 @@ pub unsafe fn check_bool_to_ordering(x: bool) -> std::cmp::Ordering {
 pub unsafe fn check_nonnull_to_ptr(x: NonNull<u8>) -> *const u8 {
     // CHECK-NOT: icmp
     // CHECK-NOT: assume
-    // OPT: %0 = icmp ne ptr %x, null
-    // OPT: call void @llvm.assume(i1 %0)
+    // OPT: call void @llvm.assume(i1 true) [ "nonnull"(ptr %x) ]
     // CHECK-NOT: icmp
     // CHECK-NOT: assume
     // CHECK: ret ptr %x
@@ -207,8 +206,7 @@ pub unsafe fn check_nonnull_to_ptr(x: NonNull<u8>) -> *const u8 {
 pub unsafe fn check_ptr_to_nonnull(x: *const u8) -> NonNull<u8> {
     // CHECK-NOT: icmp
     // CHECK-NOT: assume
-    // OPT: %0 = icmp ne ptr %x, null
-    // OPT: call void @llvm.assume(i1 %0)
+    // OPT: call void @llvm.assume(i1 true) [ "nonnull"(ptr %x) ]
     // CHECK-NOT: icmp
     // CHECK-NOT: assume
     // CHECK: ret ptr %x

tests/codegen-llvm/intrinsics/transmute.rs

@@ -379,11 +379,10 @@ pub unsafe fn check_issue_110005(x: (usize, bool)) -> Option<Box<[u8]>> {
 #[no_mangle]
 pub unsafe fn check_pair_to_dst_ref<'a>(x: (usize, usize)) -> &'a [u8] {
     // CHECK: %_0.0 = getelementptr i8, ptr null, i64 %x.0
-    // CHECK: %0 = icmp ne ptr %_0.0, null
-    // CHECK: call void @llvm.assume(i1 %0)
-    // CHECK: %1 = insertvalue { ptr, i64 } poison, ptr %_0.0, 0
-    // CHECK: %2 = insertvalue { ptr, i64 } %1, i64 %x.1, 1
-    // CHECK: ret { ptr, i64 } %2
+    // CHECK: call void @llvm.assume(i1 true) [ "nonnull"(ptr %_0.0) ]
+    // CHECK: %0 = insertvalue { ptr, i64 } poison, ptr %_0.0, 0
+    // CHECK: %1 = insertvalue { ptr, i64 } %0, i64 %x.1, 1
+    // CHECK: ret { ptr, i64 } %1
     transmute(x)
 }