From 92d94dc60d3d854285fac9ea8101fc3cc9bf813b Mon Sep 17 00:00:00 2001
From: Hamy Ratoanina <hamy.ratoanina@toposware.com>
Date: Wed, 12 Apr 2023 11:40:40 -0400
Subject: [PATCH] Use Block chain id for sys_chainid

---
 evm/src/cpu/kernel/asm/core/syscall_stubs.asm |  9 ---------
 evm/src/cpu/kernel/asm/memory/metadata.asm    | 13 +++++++++++++
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/evm/src/cpu/kernel/asm/core/syscall_stubs.asm b/evm/src/cpu/kernel/asm/core/syscall_stubs.asm
index 95b50b0b..4cb3a6d0 100644
--- a/evm/src/cpu/kernel/asm/core/syscall_stubs.asm
+++ b/evm/src/cpu/kernel/asm/core/syscall_stubs.asm
@@ -6,15 +6,6 @@ global sys_blockhash:
 global sys_prevrandao:
     // TODO: What semantics will this have for Edge?
     PANIC
-global sys_chainid:
-    // TODO: Return the block's chain ID instead of the txn's, even though they should match.
-    // stack: kexit_info
-    %charge_gas_const(@GAS_BASE)
-    // stack: kexit_info
-    %mload_txn_field(@TXN_FIELD_CHAIN_ID)
-    // stack: chain_id, kexit_info
-    SWAP1
-    EXIT_KERNEL
 global sys_log0:
     PANIC
 global sys_log1:
diff --git a/evm/src/cpu/kernel/asm/memory/metadata.asm b/evm/src/cpu/kernel/asm/memory/metadata.asm
index 4941f8d6..a297ac40 100644
--- a/evm/src/cpu/kernel/asm/memory/metadata.asm
+++ b/evm/src/cpu/kernel/asm/memory/metadata.asm
@@ -200,6 +200,19 @@ global sys_gaslimit:
     SWAP1
     EXIT_KERNEL
 
+%macro blockchainid
+    %mload_global_metadata(@GLOBAL_METADATA_BLOCK_CHAIN_ID)
+%endmacro
+
+global sys_chainid:
+    // stack: kexit_info
+    %charge_gas_const(@GAS_BASE)
+    // stack: kexit_info
+    %blockchainid
+    // stack: chain_id, kexit_info
+    SWAP1
+    EXIT_KERNEL
+
 %macro basefee
     %mload_global_metadata(@GLOBAL_METADATA_BLOCK_BASE_FEE)
 %endmacro