From 1c2cd780f3550b80c1295dcdae9765ad7d9efe85 Mon Sep 17 00:00:00 2001
From: EgorBo <egorbo@gmail.com>
Date: Tue, 12 Aug 2025 14:24:10 +0200
Subject: [PATCH 1/2] Fix assert in IsKnownConstant

---
 src/coreclr/jit/importercalls.cpp | 4 ++--
 src/coreclr/jit/morph.cpp         | 6 +++---
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/coreclr/jit/importercalls.cpp b/src/coreclr/jit/importercalls.cpp
index 4214b08958748d..a4e2e454b96616 100644
--- a/src/coreclr/jit/importercalls.cpp
+++ b/src/coreclr/jit/importercalls.cpp
@@ -3642,14 +3642,14 @@ GenTree* Compiler::impIntrinsic(CORINFO_CLASS_HANDLE    clsHnd,
                 if (op1->OperIsConst() || gtIsTypeof(op1))
                 {
                     // op1 is a known constant, replace with 'true'.
-                    retNode = gtNewIconNode(1);
+                    retNode = gtNewTrue();
                     JITDUMP("\nExpanding RuntimeHelpers.IsKnownConstant to true early\n");
                     // We can also consider FTN_ADDR here
                 }
                 else if (opts.OptimizationDisabled())
                 {
                     // It doesn't make sense to carry it as GT_INTRINSIC till Morph in Tier0
-                    retNode = gtNewIconNode(0);
+                    retNode = gtNewFalse();
                     JITDUMP("\nExpanding RuntimeHelpers.IsKnownConstant to false early\n");
                 }
                 else
diff --git a/src/coreclr/jit/morph.cpp b/src/coreclr/jit/morph.cpp
index db5443b8b26796..89193351156a42 100644
--- a/src/coreclr/jit/morph.cpp
+++ b/src/coreclr/jit/morph.cpp
@@ -8419,14 +8419,14 @@ GenTree* Compiler::fgMorphSmpOp(GenTree* tree, MorphAddrContext* mac, bool* optA
                     // We're lucky to catch a constant here while importer was not
                     JITDUMP("true\n");
                     DEBUG_DESTROY_NODE(tree, op1);
-                    tree = gtNewIconNode(1);
+                    tree = gtNewTrue();
                 }
                 else
                 {
                     JITDUMP("false\n");
-                    tree = gtWrapWithSideEffects(gtNewIconNode(0), op1, GTF_ALL_EFFECT);
+                    tree = gtWrapWithSideEffects(gtNewFalse(), op1, GTF_ALL_EFFECT);
                 }
-                tree->SetMorphed(this);
+                tree->SetMorphed(this, /*doChildren*/ true);
                 return tree;
             }
             break;

From 0c818c3a874e3b4a3e0112cf3214a86c7a5db81e Mon Sep 17 00:00:00 2001
From: EgorBo <egorbo@gmail.com>
Date: Tue, 12 Aug 2025 14:32:18 +0200
Subject: [PATCH 2/2] better impl

---
 src/coreclr/jit/morph.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/coreclr/jit/morph.cpp b/src/coreclr/jit/morph.cpp
index 89193351156a42..a4f09b64f6213a 100644
--- a/src/coreclr/jit/morph.cpp
+++ b/src/coreclr/jit/morph.cpp
@@ -8424,9 +8424,11 @@ GenTree* Compiler::fgMorphSmpOp(GenTree* tree, MorphAddrContext* mac, bool* optA
                 else
                 {
                     JITDUMP("false\n");
-                    tree = gtWrapWithSideEffects(gtNewFalse(), op1, GTF_ALL_EFFECT);
+                    tree = gtNewFalse();
+                    tree->SetMorphed(this);
+                    tree = gtWrapWithSideEffects(tree, op1, GTF_ALL_EFFECT);
                 }
-                tree->SetMorphed(this, /*doChildren*/ true);
+                tree->SetMorphed(this);
                 return tree;
             }
             break;