From 6948343b9fd4855377fd68c93b9c027d525df590 Mon Sep 17 00:00:00 2001
From: Hadrien Eyraud <hadrien.eyraud@grenoble-inp.org>
Date: Thu, 9 Jan 2025 18:39:40 +0100
Subject: [PATCH 1/2] fix: Check empty SIMD vector in inline asm

---
 .../rustc_hir_analysis/src/check/intrinsicck.rs   |  8 ++++++++
 tests/crashes/134334.rs                           |  9 ---------
 tests/ui/simd/empty-simd-vector-in-operand.rs     | 14 ++++++++++++++
 tests/ui/simd/empty-simd-vector-in-operand.stderr | 15 +++++++++++++++
 4 files changed, 37 insertions(+), 9 deletions(-)
 delete mode 100644 tests/crashes/134334.rs
 create mode 100644 tests/ui/simd/empty-simd-vector-in-operand.rs
 create mode 100644 tests/ui/simd/empty-simd-vector-in-operand.stderr

diff --git a/compiler/rustc_hir_analysis/src/check/intrinsicck.rs b/compiler/rustc_hir_analysis/src/check/intrinsicck.rs
index d63165f0f1698..32a582aadc1ca 100644
--- a/compiler/rustc_hir_analysis/src/check/intrinsicck.rs
+++ b/compiler/rustc_hir_analysis/src/check/intrinsicck.rs
@@ -29,6 +29,7 @@ enum NonAsmTypeReason<'tcx> {
     Invalid(Ty<'tcx>),
     InvalidElement(DefId, Ty<'tcx>),
     NotSizedPtr(Ty<'tcx>),
+    EmptySIMDArray(Ty<'tcx>),
 }
 
 impl<'a, 'tcx> InlineAsmCtxt<'a, 'tcx> {
@@ -102,6 +103,9 @@ impl<'a, 'tcx> InlineAsmCtxt<'a, 'tcx> {
             }
             ty::Adt(adt, args) if adt.repr().simd() => {
                 let fields = &adt.non_enum_variant().fields;
+                if fields.is_empty() {
+                    return Err(NonAsmTypeReason::EmptySIMDArray(ty));
+                }
                 let field = &fields[FieldIdx::ZERO];
                 let elem_ty = field.ty(self.tcx(), args);
 
@@ -226,6 +230,10 @@ impl<'a, 'tcx> InlineAsmCtxt<'a, 'tcx> {
                             can be used as arguments for inline assembly",
                         ).emit();
                     }
+                    NonAsmTypeReason::EmptySIMDArray(ty) => {
+                        let msg = format!("use of empty SIMD vector `{ty}`");
+                        self.infcx.dcx().struct_span_err(expr.span, msg).emit();
+                    }
                 }
                 return None;
             }
diff --git a/tests/crashes/134334.rs b/tests/crashes/134334.rs
deleted file mode 100644
index d99df7bdc1eda..0000000000000
--- a/tests/crashes/134334.rs
+++ /dev/null
@@ -1,9 +0,0 @@
-//@ known-bug: #134334
-//@ only-x86_64
-
-#[repr(simd)]
-struct A();
-
-fn main() {
-    std::arch::asm!("{}", in(xmm_reg) A());
-}
diff --git a/tests/ui/simd/empty-simd-vector-in-operand.rs b/tests/ui/simd/empty-simd-vector-in-operand.rs
new file mode 100644
index 0000000000000..ae21461eb95b9
--- /dev/null
+++ b/tests/ui/simd/empty-simd-vector-in-operand.rs
@@ -0,0 +1,14 @@
+// Regression test for issue #134224.
+
+#![feature(repr_simd)]
+
+#[repr(simd)]
+struct A();
+//~^ ERROR SIMD vector cannot be empty
+
+fn main() {
+    unsafe {
+        std::arch::asm!("{}", in(xmm_reg) A());
+        //~^ use of empty SIMD vector `A`
+    }
+}
diff --git a/tests/ui/simd/empty-simd-vector-in-operand.stderr b/tests/ui/simd/empty-simd-vector-in-operand.stderr
new file mode 100644
index 0000000000000..a0faf5f06d209
--- /dev/null
+++ b/tests/ui/simd/empty-simd-vector-in-operand.stderr
@@ -0,0 +1,15 @@
+error[E0075]: SIMD vector cannot be empty
+  --> $DIR/empty-simd-vector-in-operand.rs:6:1
+   |
+LL | struct A();
+   | ^^^^^^^^
+
+error: use of empty SIMD vector `A`
+  --> $DIR/empty-simd-vector-in-operand.rs:11:43
+   |
+LL |         std::arch::asm!("{}", in(xmm_reg) A());
+   |                                           ^^^
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0075`.

From ff699ce9f55e974e9181a800203fae9d73b90e37 Mon Sep 17 00:00:00 2001
From: Hadrien Eyraud <hadrien.eyraud@grenoble-inp.org>
Date: Mon, 3 Feb 2025 14:16:27 +0100
Subject: [PATCH 2/2] fix: running the test only on x86_64.

The test was failing on aarch64-apple-darwin.
---
 tests/ui/simd/empty-simd-vector-in-operand.rs     | 1 +
 tests/ui/simd/empty-simd-vector-in-operand.stderr | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/tests/ui/simd/empty-simd-vector-in-operand.rs b/tests/ui/simd/empty-simd-vector-in-operand.rs
index ae21461eb95b9..2a2a6c0737db6 100644
--- a/tests/ui/simd/empty-simd-vector-in-operand.rs
+++ b/tests/ui/simd/empty-simd-vector-in-operand.rs
@@ -1,4 +1,5 @@
 // Regression test for issue #134224.
+//@ only-x86_64
 
 #![feature(repr_simd)]
 
diff --git a/tests/ui/simd/empty-simd-vector-in-operand.stderr b/tests/ui/simd/empty-simd-vector-in-operand.stderr
index a0faf5f06d209..7210dddd461f0 100644
--- a/tests/ui/simd/empty-simd-vector-in-operand.stderr
+++ b/tests/ui/simd/empty-simd-vector-in-operand.stderr
@@ -1,11 +1,11 @@
 error[E0075]: SIMD vector cannot be empty
-  --> $DIR/empty-simd-vector-in-operand.rs:6:1
+  --> $DIR/empty-simd-vector-in-operand.rs:7:1
    |
 LL | struct A();
    | ^^^^^^^^
 
 error: use of empty SIMD vector `A`
-  --> $DIR/empty-simd-vector-in-operand.rs:11:43
+  --> $DIR/empty-simd-vector-in-operand.rs:12:43
    |
 LL |         std::arch::asm!("{}", in(xmm_reg) A());
    |                                           ^^^