[Mlir-commits] [mlir] [mlir][emitc] Support dense as init value of constantOp (PR #144826)

[Jianjian Guan]

https://github.com/jacquesguan created https://github.com/llvm/llvm-project/pull/144826

None

>From 2c07aa739ecb6e8d4fcba8e42b73634fc1f80689 Mon Sep 17 00:00:00 2001
From: Jianjian GUAN <jacquesguan at me.com>
Date: Thu, 19 Jun 2025 10:35:28 +0800
Subject: [PATCH] [mlir][emitc] Support dense as init value of constantOp

---
 mlir/lib/Target/Cpp/TranslateToCpp.cpp | 18 ++++++++++++++----
 mlir/test/Target/Cpp/const.mlir        |  8 ++++++++
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/mlir/lib/Target/Cpp/TranslateToCpp.cpp b/mlir/lib/Target/Cpp/TranslateToCpp.cpp
index 067a0470b14e4..480962afb5319 100644
--- a/mlir/lib/Target/Cpp/TranslateToCpp.cpp
+++ b/mlir/lib/Target/Cpp/TranslateToCpp.cpp
@@ -1328,6 +1328,16 @@ LogicalResult CppEmitter::emitAttribute(Location loc, Attribute attr) {
     }
   };
 
+  auto getDenseElementType = [&](const Type &type) {
+    if (auto arrayType = dyn_cast<ArrayType>(type)) {
+      return arrayType.getElementType();
+    }
+    if (auto tensorType = dyn_cast<TensorType>(type)) {
+      return tensorType.getElementType();
+    }
+    return Type();
+  };
+
   // Print floating point attributes.
   if (auto fAttr = dyn_cast<FloatAttr>(attr)) {
     if (!isa<Float16Type, BFloat16Type, Float32Type, Float64Type>(
@@ -1362,8 +1372,8 @@ LogicalResult CppEmitter::emitAttribute(Location loc, Attribute attr) {
     }
   }
   if (auto dense = dyn_cast<DenseIntElementsAttr>(attr)) {
-    if (auto iType = dyn_cast<IntegerType>(
-            cast<TensorType>(dense.getType()).getElementType())) {
+    if (auto iType =
+            dyn_cast<IntegerType>(getDenseElementType(dense.getType()))) {
       os << '{';
       interleaveComma(dense, os, [&](const APInt &val) {
         printInt(val, shouldMapToUnsigned(iType.getSignedness()));
@@ -1371,8 +1381,8 @@ LogicalResult CppEmitter::emitAttribute(Location loc, Attribute attr) {
       os << '}';
       return success();
     }
-    if (auto iType = dyn_cast<IndexType>(
-            cast<TensorType>(dense.getType()).getElementType())) {
+    if (auto iType =
+            dyn_cast<IndexType>(getDenseElementType(dense.getType()))) {
       os << '{';
       interleaveComma(dense, os,
                       [&](const APInt &val) { printInt(val, false); });
diff --git a/mlir/test/Target/Cpp/const.mlir b/mlir/test/Target/Cpp/const.mlir
index d3656f830c48c..2a5ff1a0f0177 100644
--- a/mlir/test/Target/Cpp/const.mlir
+++ b/mlir/test/Target/Cpp/const.mlir
@@ -16,6 +16,8 @@ func.func @emitc_constant() {
   %c8 = "emitc.constant"(){value = dense<0> : tensor<i32>} : () -> tensor<i32>
   %c9 = "emitc.constant"(){value = dense<[0, 1]> : tensor<2xindex>} : () -> tensor<2xindex>
   %c10 = "emitc.constant"(){value = dense<[[0.0, 1.0], [2.0, 3.0]]> : tensor<2x2xf32>} : () -> tensor<2x2xf32>
+  %c11 = "emitc.constant"(){value = dense<[0, 1]> : !emitc.array<2xindex>} : () -> !emitc.array<2xindex>
+  %c12 = "emitc.constant"(){value = dense<[0.0, 1.0]> : !emitc.array<2xf32>} : () -> !emitc.array<2xf32>
   return
 }
 // CPP-DEFAULT: void emitc_constant() {
@@ -33,6 +35,8 @@ func.func @emitc_constant() {
 // CPP-DEFAULT-NEXT: Tensor<int32_t> [[V8:[^ ]*]] = {0};
 // CPP-DEFAULT-NEXT: Tensor<size_t, 2> [[V9:[^ ]*]] = {0, 1};
 // CPP-DEFAULT-NEXT: Tensor<float, 2, 2> [[V10:[^ ]*]] = {0.0e+00f, 1.000000000e+00f, 2.000000000e+00f, 3.000000000e+00f};
+// CPP-DEFAULT-NEXT: size_t [[V11:[^ ]*]][2] = {0, 1};
+// CPP-DEFAULT-NEXT: float [[V12:[^ ]*]][2] = {0.0e+00f, 1.000000000e+00f};
 
 // CPP-DECLTOP: void emitc_constant() {
 // CPP-DECLTOP-NEXT: int32_t [[V0:[^ ]*]];
@@ -49,6 +53,8 @@ func.func @emitc_constant() {
 // CPP-DECLTOP-NEXT: Tensor<int32_t> [[V8:[^ ]*]];
 // CPP-DECLTOP-NEXT: Tensor<size_t, 2> [[V9:[^ ]*]];
 // CPP-DECLTOP-NEXT: Tensor<float, 2, 2> [[V10:[^ ]*]];
+// CPP-DECLTOP-NEXT: size_t [[V11:[^ ]*]][2];
+// CPP-DECLTOP-NEXT: float [[V12:[^ ]*]][2];
 // CPP-DECLTOP-NEXT: [[V0]] = INT_MAX;
 // CPP-DECLTOP-NEXT: [[V1]] = 42;
 // CPP-DECLTOP-NEXT: [[V2]] = -1;
@@ -63,3 +69,5 @@ func.func @emitc_constant() {
 // CPP-DECLTOP-NEXT: [[V8]] = {0};
 // CPP-DECLTOP-NEXT: [[V9]] = {0, 1};
 // CPP-DECLTOP-NEXT: [[V10]] = {0.0e+00f, 1.000000000e+00f, 2.000000000e+00f, 3.000000000e+00f};
+// CPP-DECLTOP-NEXT: [[V11]] = {0, 1};
+// CPP-DECLTOP-NEXT: [[V12]] = {0.0e+00f, 1.000000000e+00f};