[Mlir-commits] [mlir] [mlir][emitc] Support array result for `emitc.member` and `emitc.member_of_ptr` (PR #155224)

[Longsheng Mou]

https://github.com/CoTinker created https://github.com/llvm/llvm-project/pull/155224

This PR adds array type as a valid result type for `emitc.member` and `emitc.member_of_ptr`, enabling direct access and assignment to struct array members in EmitC.

>From 16a37facdeea9deb07be4a53f5059f840e966296 Mon Sep 17 00:00:00 2001
From: Longsheng Mou <longshengmou at gmail.com>
Date: Mon, 25 Aug 2025 16:54:25 +0800
Subject: [PATCH 1/2] [mlir][emitc] Support ArrayType result for `emitc.member`
 and `emitc.member_of_ptr`

This PR adds ArrayType as a valid result type for `emitc.member` and `emitc.member_of_ptr`, enabling direct access and assignment to struct array members in EmitC.
---
 mlir/include/mlir/Dialect/EmitC/IR/EmitC.td | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td b/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
index 59beac7d64154..9798015400a81 100644
--- a/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
+++ b/mlir/include/mlir/Dialect/EmitC/IR/EmitC.td
@@ -1051,6 +1051,8 @@ def EmitC_MemberOp : EmitC_Op<"member"> {
     ```mlir
     %0 = "emitc.member" (%arg0) {member = "a"}
         : (!emitc.lvalue<!emitc.opaque<"mystruct">>) -> !emitc.lvalue<i32>
+    %1 = "emitc.member" (%arg0) {member = "b"}
+        : (!emitc.lvalue<!emitc.opaque<"mystruct">>) -> !emitc.array<2xi32>
     ```
   }];
 
@@ -1058,7 +1060,7 @@ def EmitC_MemberOp : EmitC_Op<"member"> {
     Arg<StrAttr, "the member to access">:$member,
     EmitC_LValueOf<[EmitC_OpaqueType]>:$operand
   );
-  let results = (outs EmitC_LValueOf<[EmitCType]>);
+  let results = (outs AnyTypeOf<[EmitC_ArrayType, EmitC_LValueType]>);
 }
 
 def EmitC_MemberOfPtrOp : EmitC_Op<"member_of_ptr"> {
@@ -1073,6 +1075,9 @@ def EmitC_MemberOfPtrOp : EmitC_Op<"member_of_ptr"> {
     %0 = "emitc.member_of_ptr" (%arg0) {member = "a"}
         : (!emitc.lvalue<!emitc.ptr<!emitc.opaque<"mystruct">>>)
         -> !emitc.lvalue<i32>
+    %1 = "emitc.member_of_ptr" (%arg0) {member = "b"}
+        : (!emitc.lvalue<!emitc.ptr<!emitc.opaque<"mystruct">>>)
+        -> !emitc.array<2xi32>
     ```
   }];
 
@@ -1080,7 +1085,7 @@ def EmitC_MemberOfPtrOp : EmitC_Op<"member_of_ptr"> {
     Arg<StrAttr, "the member to access">:$member,
     EmitC_LValueOf<[EmitC_OpaqueType,EmitC_PointerType]>:$operand
   );
-  let results = (outs EmitC_LValueOf<[EmitCType]>);
+  let results = (outs AnyTypeOf<[EmitC_ArrayType, EmitC_LValueType]>);
 }
 
 def EmitC_ConditionalOp : EmitC_Op<"conditional",

>From 454d77035fffaacd51aa9586e03a487f900499da Mon Sep 17 00:00:00 2001
From: Longsheng Mou <longshengmou at gmail.com>
Date: Mon, 25 Aug 2025 16:56:17 +0800
Subject: [PATCH 2/2] add test

---
 mlir/test/Dialect/EmitC/ops.mlir | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/mlir/test/Dialect/EmitC/ops.mlir b/mlir/test/Dialect/EmitC/ops.mlir
index acee0a8d53fe4..fec8431262f37 100644
--- a/mlir/test/Dialect/EmitC/ops.mlir
+++ b/mlir/test/Dialect/EmitC/ops.mlir
@@ -286,8 +286,11 @@ func.func @assign_global(%arg0 : i32) {
 
 func.func @member_access(%arg0: !emitc.lvalue<!emitc.opaque<"mystruct">>, %arg1: !emitc.lvalue<!emitc.opaque<"mystruct_ptr">>, %arg2: !emitc.lvalue<!emitc.ptr<!emitc.opaque<"mystruct">>>) {
   %0 = "emitc.member" (%arg0) {member = "a"} : (!emitc.lvalue<!emitc.opaque<"mystruct">>) -> !emitc.lvalue<i32>
-  %1 = "emitc.member_of_ptr" (%arg1) {member = "a"} : (!emitc.lvalue<!emitc.opaque<"mystruct_ptr">>) -> !emitc.lvalue<i32>
-  %2 = "emitc.member_of_ptr" (%arg2) {member = "a"} : (!emitc.lvalue<!emitc.ptr<!emitc.opaque<"mystruct">>>) -> !emitc.lvalue<i32>
+  %1 = "emitc.member" (%arg0) {member = "b"} : (!emitc.lvalue<!emitc.opaque<"mystruct">>) -> !emitc.array<2xi32>
+  %2 = "emitc.member_of_ptr" (%arg1) {member = "a"} : (!emitc.lvalue<!emitc.opaque<"mystruct_ptr">>) -> !emitc.lvalue<i32>
+  %3 = "emitc.member_of_ptr" (%arg1) {member = "b"} : (!emitc.lvalue<!emitc.opaque<"mystruct_ptr">>) -> !emitc.array<2xi32>
+  %4 = "emitc.member_of_ptr" (%arg2) {member = "a"} : (!emitc.lvalue<!emitc.ptr<!emitc.opaque<"mystruct">>>) -> !emitc.lvalue<i32>
+  %5 = "emitc.member_of_ptr" (%arg2) {member = "b"} : (!emitc.lvalue<!emitc.ptr<!emitc.opaque<"mystruct">>>) -> !emitc.array<2xi32>
   return
 }