From 08c5498e90aee83e1b91fa5f72a26f513c38dd13 Mon Sep 17 00:00:00 2001
From: Chris Dodd <cdodd@nvidia.com>
Date: Mon, 3 Feb 2025 04:25:18 +0000
Subject: [PATCH] Clean up typeCheckTypes a bit; another test

---
 frontends/p4/typeChecking/typeCheckTypes.cpp  | 16 +++------
 testdata/p4_16_samples/array3.p4              | 30 ++++++++++++++++
 .../p4_16_samples_outputs/array3-first.p4     | 27 ++++++++++++++
 .../p4_16_samples_outputs/array3-frontend.p4  | 27 ++++++++++++++
 .../p4_16_samples_outputs/array3-midend.p4    | 36 +++++++++++++++++++
 testdata/p4_16_samples_outputs/array3.p4      | 27 ++++++++++++++
 .../p4_16_samples_outputs/array3.p4-stderr    |  0
 7 files changed, 151 insertions(+), 12 deletions(-)
 create mode 100644 testdata/p4_16_samples/array3.p4
 create mode 100644 testdata/p4_16_samples_outputs/array3-first.p4
 create mode 100644 testdata/p4_16_samples_outputs/array3-frontend.p4
 create mode 100644 testdata/p4_16_samples_outputs/array3-midend.p4
 create mode 100644 testdata/p4_16_samples_outputs/array3.p4
 create mode 100644 testdata/p4_16_samples_outputs/array3.p4-stderr

diff --git a/frontends/p4/typeChecking/typeCheckTypes.cpp b/frontends/p4/typeChecking/typeCheckTypes.cpp
index 10f934ca114..c9b5eb12d28 100644
--- a/frontends/p4/typeChecking/typeCheckTypes.cpp
+++ b/frontends/p4/typeChecking/typeCheckTypes.cpp
@@ -47,6 +47,7 @@ bool hasVarbitsOrUnions(const TypeMap *typeMap, const IR::Type *type) {
 
 bool TypeInferenceBase::onlyBitsOrBitStructs(const IR::Type *type) const {
     // called for a canonical type
+    while (auto *st = type->to<IR::Type_Stack>()) type = st->elementType;
     if (type->is<IR::Type_Bits>() || type->is<IR::Type_Boolean>() || type->is<IR::Type_SerEnum>()) {
         return true;
     } else if (auto ht = type->to<IR::Type_Struct>()) {
@@ -424,18 +425,9 @@ const IR::Node *TypeInferenceBase::postorder(const IR::StructField *field) {
 const IR::Node *TypeInferenceBase::postorder(const IR::Type_Header *type) {
     auto canon = setTypeType(type);
     auto validator = [this](const IR::Type *t) {
-        while (1) {
-            if (t->is<IR::Type_Newtype>())
-                t = getTypeType(t->to<IR::Type_Newtype>()->type);
-            else if (auto *st = t->to<IR::Type_Stack>())
-                t = st->elementType;
-            else
-                break;
-        }
-        return t->is<IR::Type_Bits>() || t->is<IR::Type_Varbits>() ||
-               (t->is<IR::Type_Struct>() && onlyBitsOrBitStructs(t)) || t->is<IR::Type_SerEnum>() ||
-               t->is<IR::Type_Boolean>() || t->is<IR::Type_Var>() ||
-               t->is<IR::Type_SpecializedCanonical>();
+        while (t->is<IR::Type_Newtype>()) t = getTypeType(t->to<IR::Type_Newtype>()->type);
+        return onlyBitsOrBitStructs(t) || t->is<IR::Type_Varbits>() ||
+               t->is<IR::Type_Var>() || t->is<IR::Type_SpecializedCanonical>();
     };
     validateFields(canon, validator);
     return type;
diff --git a/testdata/p4_16_samples/array3.p4 b/testdata/p4_16_samples/array3.p4
new file mode 100644
index 00000000000..37549afce71
--- /dev/null
+++ b/testdata/p4_16_samples/array3.p4
@@ -0,0 +1,30 @@
+control proto<P>(inout P pkt);
+package top<P>(proto<P> p);
+
+struct S {
+    bit<16> f1;
+    bit<8>[16] nested_arr;
+    bit<16> f2;
+}
+
+header data_t {
+    S[16]  arr;
+    bit<4>     w;
+    bit<4>     x;
+    bit<4>     y;
+    bit<4>     z;
+}
+
+struct headers {
+    data_t      data;
+}
+
+
+control c(inout headers hdr) {
+    apply {
+        hdr.data.arr[0].nested_arr[1] =
+            hdr.data.arr[2].nested_arr[3];
+    }
+}
+
+top(c()) main;
diff --git a/testdata/p4_16_samples_outputs/array3-first.p4 b/testdata/p4_16_samples_outputs/array3-first.p4
new file mode 100644
index 00000000000..fe5f1f08e55
--- /dev/null
+++ b/testdata/p4_16_samples_outputs/array3-first.p4
@@ -0,0 +1,27 @@
+control proto<P>(inout P pkt);
+package top<P>(proto<P> p);
+struct S {
+    bit<16>    f1;
+    bit<8>[16] nested_arr;
+    bit<16>    f2;
+}
+
+header data_t {
+    S[16]  arr;
+    bit<4> w;
+    bit<4> x;
+    bit<4> y;
+    bit<4> z;
+}
+
+struct headers {
+    data_t data;
+}
+
+control c(inout headers hdr) {
+    apply {
+        hdr.data.arr[0].nested_arr[1] = hdr.data.arr[2].nested_arr[3];
+    }
+}
+
+top<headers>(c()) main;
diff --git a/testdata/p4_16_samples_outputs/array3-frontend.p4 b/testdata/p4_16_samples_outputs/array3-frontend.p4
new file mode 100644
index 00000000000..fe5f1f08e55
--- /dev/null
+++ b/testdata/p4_16_samples_outputs/array3-frontend.p4
@@ -0,0 +1,27 @@
+control proto<P>(inout P pkt);
+package top<P>(proto<P> p);
+struct S {
+    bit<16>    f1;
+    bit<8>[16] nested_arr;
+    bit<16>    f2;
+}
+
+header data_t {
+    S[16]  arr;
+    bit<4> w;
+    bit<4> x;
+    bit<4> y;
+    bit<4> z;
+}
+
+struct headers {
+    data_t data;
+}
+
+control c(inout headers hdr) {
+    apply {
+        hdr.data.arr[0].nested_arr[1] = hdr.data.arr[2].nested_arr[3];
+    }
+}
+
+top<headers>(c()) main;
diff --git a/testdata/p4_16_samples_outputs/array3-midend.p4 b/testdata/p4_16_samples_outputs/array3-midend.p4
new file mode 100644
index 00000000000..58b57571e72
--- /dev/null
+++ b/testdata/p4_16_samples_outputs/array3-midend.p4
@@ -0,0 +1,36 @@
+control proto<P>(inout P pkt);
+package top<P>(proto<P> p);
+struct S {
+    bit<16>    f1;
+    bit<8>[16] nested_arr;
+    bit<16>    f2;
+}
+
+header data_t {
+    S[16]  arr;
+    bit<4> w;
+    bit<4> x;
+    bit<4> y;
+    bit<4> z;
+}
+
+struct headers {
+    data_t data;
+}
+
+control c(inout headers hdr) {
+    @hidden action array3l25() {
+        hdr.data.arr[0].nested_arr[1] = hdr.data.arr[2].nested_arr[3];
+    }
+    @hidden table tbl_array3l25 {
+        actions = {
+            array3l25();
+        }
+        const default_action = array3l25();
+    }
+    apply {
+        tbl_array3l25.apply();
+    }
+}
+
+top<headers>(c()) main;
diff --git a/testdata/p4_16_samples_outputs/array3.p4 b/testdata/p4_16_samples_outputs/array3.p4
new file mode 100644
index 00000000000..c8d032bb310
--- /dev/null
+++ b/testdata/p4_16_samples_outputs/array3.p4
@@ -0,0 +1,27 @@
+control proto<P>(inout P pkt);
+package top<P>(proto<P> p);
+struct S {
+    bit<16>    f1;
+    bit<8>[16] nested_arr;
+    bit<16>    f2;
+}
+
+header data_t {
+    S[16]  arr;
+    bit<4> w;
+    bit<4> x;
+    bit<4> y;
+    bit<4> z;
+}
+
+struct headers {
+    data_t data;
+}
+
+control c(inout headers hdr) {
+    apply {
+        hdr.data.arr[0].nested_arr[1] = hdr.data.arr[2].nested_arr[3];
+    }
+}
+
+top(c()) main;
diff --git a/testdata/p4_16_samples_outputs/array3.p4-stderr b/testdata/p4_16_samples_outputs/array3.p4-stderr
new file mode 100644
index 00000000000..e69de29bb2d