Auto merge of #100999 - nnethercote:shrink-FnAbi, r=bjorn3

Shrink `FnAbi`

Because they can take up a lot of memory in debug and release builds.

r? `@bjorn3`

1 files changed, 4 insertions, 6 deletions

diff --git a/compiler/rustc_const_eval/src/interpret/terminator.rs b/compiler/rustc_const_eval/src/interpret/terminator.rs
index f23fa573100..a71a5d4b833 100644
--- a/compiler/rustc_const_eval/src/interpret/terminator.rs
+++ b/compiler/rustc_const_eval/src/interpret/terminator.rs
@@ -214,10 +214,8 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 _ => false,
             }
         };
-        // Padding must be fully equal.
-        let pad_compat = || caller_abi.pad == callee_abi.pad;
         // When comparing the PassMode, we have to be smart about comparing the attributes.
-        let arg_attr_compat = |a1: ArgAttributes, a2: ArgAttributes| {
+        let arg_attr_compat = |a1: &ArgAttributes, a2: &ArgAttributes| {
             // There's only one regular attribute that matters for the call ABI: InReg.
             // Everything else is things like noalias, dereferencable, nonnull, ...
             // (This also applies to pointee_size, pointee_align.)
@@ -232,13 +230,13 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             }
             return true;
         };
-        let mode_compat = || match (caller_abi.mode, callee_abi.mode) {
+        let mode_compat = || match (&caller_abi.mode, &callee_abi.mode) {
             (PassMode::Ignore, PassMode::Ignore) => true,
             (PassMode::Direct(a1), PassMode::Direct(a2)) => arg_attr_compat(a1, a2),
             (PassMode::Pair(a1, b1), PassMode::Pair(a2, b2)) => {
                 arg_attr_compat(a1, a2) && arg_attr_compat(b1, b2)
             }
-            (PassMode::Cast(c1), PassMode::Cast(c2)) => c1 == c2,
+            (PassMode::Cast(c1, pad1), PassMode::Cast(c2, pad2)) => c1 == c2 && pad1 == pad2,
             (
                 PassMode::Indirect { attrs: a1, extra_attrs: None, on_stack: s1 },
                 PassMode::Indirect { attrs: a2, extra_attrs: None, on_stack: s2 },
@@ -250,7 +248,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             _ => false,
         };
 
-        if layout_compat() && pad_compat() && mode_compat() {
+        if layout_compat() && mode_compat() {
             return true;
         }
         trace!(