Auto merge of #137271 - nikic:gep-nuw-2, r=scottmcm

Emit getelementptr inbounds nuw for pointer::add()

Lower pointer::add (via intrinsic::offset with unsigned offset) to getelementptr inbounds nuw on LLVM versions that support it. This lets LLVM make use of the pre-condition that the offset addition does not wrap in an unsigned sense. Together with inbounds, this also implies that the offset is non-negative.

Fixes https://github.com/rust-lang/rust/issues/137217.

4 files changed, 7 insertions, 7 deletions

diff --git a/tests/codegen/gep-index.rs b/tests/codegen/gep-index.rs
index 1f5e8855910..bfb2511af87 100644
--- a/tests/codegen/gep-index.rs
+++ b/tests/codegen/gep-index.rs
@@ -11,27 +11,27 @@ struct Foo(i32, i32);
 // CHECK-LABEL: @index_on_struct(
 #[no_mangle]
 fn index_on_struct(a: &[Foo], index: usize) -> &Foo {
-    // CHECK: getelementptr inbounds %Foo, ptr %a.0, {{i64|i32}} %index
+    // CHECK: getelementptr inbounds{{( nuw)?}} %Foo, ptr %a.0, {{i64|i32}} %index
     &a[index]
 }
 
 // CHECK-LABEL: @offset_on_struct(
 #[no_mangle]
 fn offset_on_struct(a: *const Foo, index: usize) -> *const Foo {
-    // CHECK: getelementptr inbounds %Foo, ptr %a, {{i64|i32}} %index
+    // CHECK: getelementptr inbounds{{( nuw)?}} %Foo, ptr %a, {{i64|i32}} %index
     unsafe { a.add(index) }
 }
 
 // CHECK-LABEL: @index_on_i32(
 #[no_mangle]
 fn index_on_i32(a: &[i32], index: usize) -> &i32 {
-    // CHECK: getelementptr inbounds i32, ptr %a.0, {{i64|i32}} %index
+    // CHECK: getelementptr inbounds{{( nuw)?}} i32, ptr %a.0, {{i64|i32}} %index
     &a[index]
 }
 
 // CHECK-LABEL: @offset_on_i32(
 #[no_mangle]
 fn offset_on_i32(a: *const i32, index: usize) -> *const i32 {
-    // CHECK: getelementptr inbounds i32, ptr %a, {{i64|i32}} %index
+    // CHECK: getelementptr inbounds{{( nuw)?}} i32, ptr %a, {{i64|i32}} %index
     unsafe { a.add(index) }
 }
diff --git a/tests/codegen/intrinsics/offset.rs b/tests/codegen/intrinsics/offset.rs
index d76d3e705ab..cf0c7c7ac7d 100644
--- a/tests/codegen/intrinsics/offset.rs
+++ b/tests/codegen/intrinsics/offset.rs
@@ -27,7 +27,7 @@ pub unsafe fn offset_isize(p: *const u32, d: isize) -> *const u32 {
 // CHECK-SAME: (ptr noundef %p, [[SIZE]] noundef %d)
 #[no_mangle]
 pub unsafe fn offset_usize(p: *const u64, d: usize) -> *const u64 {
-    // CHECK: %[[R:.*]] = getelementptr inbounds i64, ptr %p, [[SIZE]] %d
+    // CHECK: %[[R:.*]] = getelementptr inbounds{{( nuw)?}} i64, ptr %p, [[SIZE]] %d
     // CHECK-NEXT: ret ptr %[[R]]
     offset(p, d)
 }
diff --git a/tests/codegen/intrinsics/ptr_metadata.rs b/tests/codegen/intrinsics/ptr_metadata.rs
index 87a32fa3d24..044dbc20486 100644
--- a/tests/codegen/intrinsics/ptr_metadata.rs
+++ b/tests/codegen/intrinsics/ptr_metadata.rs
@@ -28,7 +28,7 @@ pub unsafe fn dyn_byte_offset(
     p: *const dyn std::fmt::Debug,
     n: usize,
 ) -> *const dyn std::fmt::Debug {
-    // CHECK: %[[Q:.+]] = getelementptr inbounds i8, ptr %p.0, i64 %n
+    // CHECK: %[[Q:.+]] = getelementptr inbounds{{( nuw)?}} i8, ptr %p.0, i64 %n
     // CHECK: %[[TEMP1:.+]] = insertvalue { ptr, ptr } poison, ptr %[[Q]], 0
     // CHECK: %[[TEMP2:.+]] = insertvalue { ptr, ptr } %[[TEMP1]], ptr %p.1, 1
     // CHECK: ret { ptr, ptr } %[[TEMP2]]
diff --git a/tests/codegen/ptr-arithmetic.rs b/tests/codegen/ptr-arithmetic.rs
index ecb44b30f5c..fc4441ef448 100644
--- a/tests/codegen/ptr-arithmetic.rs
+++ b/tests/codegen/ptr-arithmetic.rs
@@ -6,7 +6,7 @@
 // CHECK-SAME: [[WORD:i[0-9]+]] noundef %n)
 #[no_mangle]
 pub unsafe fn i32_add(p: *const i32, n: usize) -> *const i32 {
-    // CHECK: %[[TEMP:.+]] = getelementptr inbounds i32, ptr %p, [[WORD]] %n
+    // CHECK: %[[TEMP:.+]] = getelementptr inbounds{{( nuw)?}} i32, ptr %p, [[WORD]] %n
     // CHECK: ret ptr %[[TEMP]]
     p.add(n)
 }