From 4449d8424cde5e2c7715baad45af5c731547fd1f Mon Sep 17 00:00:00 2001
From: Sacul0457Deve <183588943+Sacul0457@users.noreply.github.com.>
Date: Sun, 8 Feb 2026 09:05:05 +0800
Subject: [PATCH 1/2] optimise _ITER_CHECK_RANGE and _ITER_CHECK_LIST

---
 Python/optimizer_bytecodes.c | 14 ++++++++++++++
 Python/optimizer_cases.c.h   | 12 ++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/Python/optimizer_bytecodes.c b/Python/optimizer_bytecodes.c
index 0863d5dd8f8df7..3c2be7c8d617a0 100644
--- a/Python/optimizer_bytecodes.c
+++ b/Python/optimizer_bytecodes.c
@@ -1088,6 +1088,20 @@ dummy_func(void) {
         sym_set_type(iter, &PyTuple_Type);
     }
 
+    op(_ITER_CHECK_LIST, (iter, null_or_index -- iter, null_or_index)) {
+        if (sym_matches_type(iter, &PyList_Type)) {
+            ADD_OP(_NOP, 0, 0);
+        }
+        sym_set_type(iter, &PyList_Type);
+    }
+
+    op(_ITER_CHECK_RANGE, (iter, null_or_index -- iter, null_or_index)) {
+        if (sym_matches_type(iter, &PyRange_Type)) {
+            ADD_OP(_NOP, 0, 0);
+        }
+        sym_set_type(iter, &PyRange_Type);
+    }
+
     op(_ITER_NEXT_RANGE, (iter, null_or_index -- iter, null_or_index, next)) {
        next = sym_new_type(ctx, &PyLong_Type);
     }
diff --git a/Python/optimizer_cases.c.h b/Python/optimizer_cases.c.h
index 9a51d2fa366661..84ef9228dbb36a 100644
--- a/Python/optimizer_cases.c.h
+++ b/Python/optimizer_cases.c.h
@@ -2621,6 +2621,12 @@
         /* _INSTRUMENTED_FOR_ITER is not a viable micro-op for tier 2 */
 
         case _ITER_CHECK_LIST: {
+            JitOptRef iter;
+            iter = stack_pointer[-2];
+            if (sym_matches_type(iter, &PyList_Type)) {
+                ADD_OP(_NOP, 0, 0);
+            }
+            sym_set_type(iter, &PyList_Type);
             break;
         }
 
@@ -2669,6 +2675,12 @@
         }
 
         case _ITER_CHECK_RANGE: {
+            JitOptRef iter;
+            iter = stack_pointer[-2];
+            if (sym_matches_type(iter, &PyRange_Type)) {
+                ADD_OP(_NOP, 0, 0);
+            }
+            sym_set_type(iter, &PyRange_Type);
             break;
         }
 

From 1490bd8d7201a1e5fdb5f277cfe60d9ad682c7eb Mon Sep 17 00:00:00 2001
From: "blurb-it[bot]" <43283697+blurb-it[bot]@users.noreply.github.com>
Date: Sun, 8 Feb 2026 01:19:51 +0000
Subject: [PATCH 2/2] =?UTF-8?q?=F0=9F=93=9C=F0=9F=A4=96=20Added=20by=20blu?=
 =?UTF-8?q?rb=5Fit.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../2026-02-08-01-19-50.gh-issue-131798.PaWDNH.rst               | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 Misc/NEWS.d/next/Core_and_Builtins/2026-02-08-01-19-50.gh-issue-131798.PaWDNH.rst

diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2026-02-08-01-19-50.gh-issue-131798.PaWDNH.rst b/Misc/NEWS.d/next/Core_and_Builtins/2026-02-08-01-19-50.gh-issue-131798.PaWDNH.rst
new file mode 100644
index 00000000000000..fe80c2d911b6ee
--- /dev/null
+++ b/Misc/NEWS.d/next/Core_and_Builtins/2026-02-08-01-19-50.gh-issue-131798.PaWDNH.rst
@@ -0,0 +1 @@
+Optimize ``_ITER_CHECK_RANGE`` and ``_ITER_CHECK_LIST`` in the JIT