Merge pull request #1314 from topos-protocol/refactor_wcopy

Refactor `%wcopy` and unify {ext}codecopy related code
0xPolygonZero · Oct 27, 2023 · 0258ad4 · 0258ad4
2 parents 666a155 + 6f52b76
commit 0258ad4
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Showing 5 changed files with 139 additions and 202 deletions.
diff --git a/evm/src/cpu/kernel/asm/account_code.asm b/evm/src/cpu/kernel/asm/account_code.asm
@@ -80,110 +80,6 @@ global extcodesize:
     // stack: extcodesize(address), retdest
     SWAP1 JUMP
 
-%macro extcodecopy
-    // stack: address, dest_offset, offset, size
-    %stack (address, dest_offset, offset, size) -> (address, dest_offset, offset, size, %%after)
-    %jump(extcodecopy)
-%%after:
-%endmacro
-
-// Pre stack: kexit_info, address, dest_offset, offset, size
-// Post stack: (empty)
-global sys_extcodecopy:
-    %stack (kexit_info, address, dest_offset, offset, size)
-        -> (address, dest_offset, offset, size, kexit_info)
-    %u256_to_addr DUP1 %insert_accessed_addresses
-    // stack: cold_access, address, dest_offset, offset, size, kexit_info
-    PUSH @GAS_COLDACCOUNTACCESS_MINUS_WARMACCESS
-    MUL
-    PUSH @GAS_WARMACCESS
-    ADD
-    // stack: Gaccess, address, dest_offset, offset, size, kexit_info
-
-    DUP5
-    // stack: size, Gaccess, address, dest_offset, offset, size, kexit_info
-    ISZERO %jumpi(sys_extcodecopy_empty)
-
-    // stack: Gaccess, address, dest_offset, offset, size, kexit_info
-    DUP5 %num_bytes_to_num_words %mul_const(@GAS_COPY) ADD
-    %stack (gas, address, dest_offset, offset, size, kexit_info) -> (gas, kexit_info, address, dest_offset, offset, size)
-    %charge_gas
-
-    %stack (kexit_info, address, dest_offset, offset, size) -> (dest_offset, size, kexit_info, address, dest_offset, offset, size)
-    %add_or_fault
-    // stack: expanded_num_bytes, kexit_info, address, dest_offset, offset, size
-    DUP1 %ensure_reasonable_offset
-    %update_mem_bytes
-
-    %stack (kexit_info, address, dest_offset, offset, size) -> (address, dest_offset, offset, size, kexit_info)
-    %extcodecopy
-    // stack: kexit_info
-    EXIT_KERNEL
-
-sys_extcodecopy_empty:
-    %stack (Gaccess, address, dest_offset, offset, size, kexit_info) -> (Gaccess, kexit_info)
-    %charge_gas
-    EXIT_KERNEL
-
-
-// Pre stack: address, dest_offset, offset, size, retdest
-// Post stack: (empty)
-global extcodecopy:
-    // stack: address, dest_offset, offset, size, retdest
-    %stack (address, dest_offset, offset, size, retdest)
-        -> (address, 0, @SEGMENT_KERNEL_ACCOUNT_CODE, extcodecopy_contd, size, offset, dest_offset, retdest)
-    %jump(load_code)
-
-extcodecopy_contd:
-    // stack: code_size, size, offset, dest_offset, retdest
-    DUP1 DUP4
-    // stack: offset, code_size, code_size, size, offset, dest_offset, retdest
-    GT %jumpi(extcodecopy_large_offset)
-
-    // stack: code_size, size, offset, dest_offset, retdest
-    DUP3 DUP3 ADD
-    // stack: offset + size, code_size, size, offset, dest_offset, retdest
-    DUP2 GT %jumpi(extcodecopy_within_bounds)
-
-    // stack: code_size, size, offset, dest_offset, retdest
-    DUP3 DUP3 ADD
-    // stack: offset + size, code_size, size, offset, dest_offset, retdest
-    SUB
-    // stack: extra_size = offset + size - code_size, size, offset, dest_offset, retdest
-    DUP1 DUP3 SUB
-    // stack: copy_size = size - extra_size, extra_size, size, offset, dest_offset, retdest
-
-    // Compute the new dest_offset after actual copies, at which we will start padding with zeroes.
-    DUP1 DUP6 ADD
-    // stack: new_dest_offset, copy_size, extra_size, size, offset, dest_offset, retdest
-
-    GET_CONTEXT
-    %stack (context, new_dest_offset, copy_size, extra_size, size, offset, dest_offset, retdest) ->
-        (context, @SEGMENT_MAIN_MEMORY, dest_offset, 0, @SEGMENT_KERNEL_ACCOUNT_CODE, offset, copy_size, extcodecopy_end, new_dest_offset, extra_size, retdest)
-    %jump(memcpy_bytes)
-
-extcodecopy_within_bounds:
-    // stack: code_size, size, offset, dest_offset, retdest
-    GET_CONTEXT
-    %stack (context, code_size, size, offset, dest_offset, retdest) ->
-        (context, @SEGMENT_MAIN_MEMORY, dest_offset, 0, @SEGMENT_KERNEL_ACCOUNT_CODE, offset, size, retdest)
-    %jump(memcpy_bytes)
-
-// Same as extcodecopy_large_offset, but without `offset` in the stack.
-extcodecopy_end:
-    // stack: dest_offset, size, retdest
-    GET_CONTEXT
-    %stack (context, dest_offset, size, retdest) ->
-        (context, @SEGMENT_MAIN_MEMORY, dest_offset, size, retdest)
-    %jump(memset)
-
-extcodecopy_large_offset:
-    // offset is larger than the code size. So we just have to write zeros.
-    // stack: code_size, size, offset, dest_offset, retdest
-    GET_CONTEXT
-    %stack (context, code_size, size, offset, dest_offset, retdest) -> (context, @SEGMENT_MAIN_MEMORY, dest_offset, size, retdest)
-    %jump(memset)
-
 // Loads the code at `address` into memory, at the given context and segment, starting at offset 0.
 // Checks that the hash of the loaded code corresponds to the `codehash` in the state trie.
 // Pre stack: address, ctx, segment, retdest

diff --git a/evm/src/cpu/kernel/asm/memory/memcpy.asm b/evm/src/cpu/kernel/asm/memory/memcpy.asm
@@ -42,12 +42,6 @@ global memcpy:
     // Continue the loop.
     %jump(memcpy)
 
-memcpy_finish:
-    // stack: DST, SRC, count, retdest
-    %pop7
-    // stack: retdest
-    JUMP
-
 %macro memcpy
     %stack (dst: 3, src: 3, count) -> (dst, src, count, %%after)
     %jump(memcpy)
@@ -63,7 +57,7 @@ global memcpy_bytes:
     // stack: count, DST, SRC, count, retdest
     ISZERO
     // stack: count == 0, DST, SRC, count, retdest
-    %jumpi(memcpy_bytes_empty)
+    %jumpi(memcpy_finish)
 
     // stack: DST, SRC, count, retdest
 
@@ -126,12 +120,8 @@ memcpy_bytes_finish:
     MSTORE_32BYTES
     // stack: DST, SRC, count, retdest
 
-    %pop7
-    // stack: retdest
-    JUMP
-
-memcpy_bytes_empty:
-    // stack: DST, SRC, 0, retdest
+memcpy_finish:
+    // stack: DST, SRC, count, retdest
     %pop7
     // stack: retdest
     JUMP

diff --git a/evm/src/cpu/kernel/asm/memory/syscalls.asm b/evm/src/cpu/kernel/asm/memory/syscalls.asm
@@ -70,15 +70,10 @@ calldataload_large_offset:
     %stack (kexit_info, i) -> (kexit_info, 0)
     EXIT_KERNEL
 
-// Macro for {CALLDATA,CODE,RETURNDATA}COPY (W_copy in Yellow Paper).
+// Macro for {CALLDATA, RETURNDATA}COPY (W_copy in Yellow Paper).
 %macro wcopy(segment, context_metadata_size)
     // stack: kexit_info, dest_offset, offset, size
-    PUSH @GAS_VERYLOW
-    DUP5
-    // stack: size, Gverylow, kexit_info, dest_offset, offset, size
-    ISZERO %jumpi(wcopy_empty)
-    // stack: Gverylow, kexit_info, dest_offset, offset, size
-    DUP5 %num_bytes_to_num_words %mul_const(@GAS_COPY) ADD %charge_gas
+    %wcopy_charge_gas
 
     %stack (kexit_info, dest_offset, offset, size) -> (dest_offset, size, kexit_info, dest_offset, offset, size)
     %add_or_fault
@@ -92,54 +87,44 @@ calldataload_large_offset:
     // stack: offset, total_size, kexit_info, dest_offset, offset, size
     GT %jumpi(wcopy_large_offset)
 
+    // stack: kexit_info, dest_offset, offset, size
+    GET_CONTEXT
     PUSH $segment
-    %mload_context_metadata($context_metadata_size)
-    // stack: total_size, segment, kexit_info, dest_offset, offset, size
-    DUP6 DUP6 ADD
-    // stack: offset + size, total_size, segment, kexit_info, dest_offset, offset, size
-    LT %jumpi(wcopy_within_bounds)
-
-    %mload_context_metadata($context_metadata_size)
-    // stack: total_size, segment, kexit_info, dest_offset, offset, size
-    DUP6 DUP6 ADD
-    // stack: offset + size, total_size, segment, kexit_info, dest_offset, offset, size
-    SUB // extra_size = offset + size - total_size
-    // stack: extra_size, segment, kexit_info, dest_offset, offset, size
-    DUP1 DUP7 SUB
-    // stack: copy_size = size - extra_size, extra_size, segment, kexit_info, dest_offset, offset, size
-
-    // Compute the new dest_offset after actual copies, at which we will start padding with zeroes.
-    DUP1 DUP6 ADD
-    // stack: new_dest_offset, copy_size, extra_size, segment, kexit_info, dest_offset, offset, size
+    // stack: segment, context, kexit_info, dest_offset, offset, size
+    %jump(wcopy_within_bounds)
+%endmacro
 
-    GET_CONTEXT
-    %stack (context, new_dest_offset, copy_size, extra_size, segment, kexit_info, dest_offset, offset, size) ->
-        (context, @SEGMENT_MAIN_MEMORY, dest_offset, context, segment, offset, copy_size, wcopy_over_range, new_dest_offset, extra_size, kexit_info)
-    %jump(memcpy_bytes)
+%macro wcopy_charge_gas
+    // stack: kexit_info, dest_offset, offset, size
+    PUSH @GAS_VERYLOW
+    DUP5
+    // stack: size, Gverylow, kexit_info, dest_offset, offset, size
+    ISZERO %jumpi(wcopy_empty)
+    // stack: Gverylow, kexit_info, dest_offset, offset, size
+    DUP5 %num_bytes_to_num_words %mul_const(@GAS_COPY) ADD %charge_gas
 %endmacro
 
+
+codecopy_within_bounds:
+    // stack: total_size, segment, src_ctx, kexit_info, dest_offset, offset, size
+    POP
 wcopy_within_bounds:
-    // stack: segment, kexit_info, dest_offset, offset, size
+    // stack: segment, src_ctx, kexit_info, dest_offset, offset, size
     GET_CONTEXT
-    %stack (context, segment, kexit_info, dest_offset, offset, size) ->
-        (context, @SEGMENT_MAIN_MEMORY, dest_offset, context, segment, offset, size, wcopy_after, kexit_info)
+    %stack (context, segment, src_ctx, kexit_info, dest_offset, offset, size) ->
+        (context, @SEGMENT_MAIN_MEMORY, dest_offset, src_ctx, segment, offset, size, wcopy_after, kexit_info)
     %jump(memcpy_bytes)
 
-
-// Same as wcopy_large_offset, but without `offset` in the stack.
-wcopy_over_range:
-    // stack: dest_offset, size, kexit_info
-    GET_CONTEXT
-    %stack (context, dest_offset, size, kexit_info) ->
-        (context, @SEGMENT_MAIN_MEMORY, dest_offset, size, wcopy_after, kexit_info)
-    %jump(memset)
-
 wcopy_empty:
     // stack: Gverylow, kexit_info, dest_offset, offset, size
     %charge_gas
     %stack (kexit_info, dest_offset, offset, size) -> (kexit_info)
     EXIT_KERNEL
 
+
+codecopy_large_offset:
+    // stack: total_size, src_ctx, kexit_info, dest_offset, offset, size
+    %pop2
 wcopy_large_offset:
     // offset is larger than the size of the {CALLDATA,CODE,RETURNDATA}. So we just have to write zeros.
     // stack: kexit_info, dest_offset, offset, size
@@ -152,64 +137,107 @@ wcopy_after:
     // stack: kexit_info
     EXIT_KERNEL
 
+// Pre stack: kexit_info, dest_offset, offset, size
+// Post stack: (empty)
 global sys_calldatacopy:
     %wcopy(@SEGMENT_CALLDATA, @CTX_METADATA_CALLDATA_SIZE)
 
-global sys_codecopy:
-    %wcopy(@SEGMENT_CODE, @CTX_METADATA_CODE_SIZE)
-
-// Same as %wcopy but with overflow checks.
+// Pre stack: kexit_info, dest_offset, offset, size
+// Post stack: (empty)
 global sys_returndatacopy:
+    DUP4 DUP4 %add_or_fault // Overflow check
+    %mload_context_metadata(@CTX_METADATA_RETURNDATA_SIZE) LT %jumpi(fault_exception) // Data len check
+
+    %wcopy(@SEGMENT_RETURNDATA, @CTX_METADATA_RETURNDATA_SIZE)
+
+// Pre stack: kexit_info, dest_offset, offset, size
+// Post stack: (empty)
+global sys_codecopy:
     // stack: kexit_info, dest_offset, offset, size
-    PUSH @GAS_VERYLOW
-    // stack: Gverylow, kexit_info, dest_offset, offset, size
-    DUP5 %num_bytes_to_num_words %mul_const(@GAS_COPY) ADD %charge_gas
+    %wcopy_charge_gas
 
     %stack (kexit_info, dest_offset, offset, size) -> (dest_offset, size, kexit_info, dest_offset, offset, size)
     %add_or_fault
     // stack: expanded_num_bytes, kexit_info, dest_offset, offset, size, kexit_info
     DUP1 %ensure_reasonable_offset
     %update_mem_bytes
-    // stack: kexit_info, dest_offset, offset, size, kexit_info
-    DUP4 DUP4 %add_or_fault // Overflow check
-    %mload_context_metadata(@CTX_METADATA_RETURNDATA_SIZE) LT %jumpi(fault_exception) // Data len check
 
-    // stack:  kexit_info, dest_offset, offset, size
-    DUP4
-    // stack:  size, kexit_info, dest_offset, offset, size
-    ISZERO %jumpi(returndatacopy_empty)
+    GET_CONTEXT
+    %mload_context_metadata(@CTX_METADATA_CODE_SIZE)
+    // stack: code_size, ctx, kexit_info, dest_offset, offset, size
+    %codecopy_after_checks(@SEGMENT_CODE)
+
+
+// Pre stack: kexit_info, address, dest_offset, offset, size
+// Post stack: (empty)
+global sys_extcodecopy:
+    %stack (kexit_info, address, dest_offset, offset, size)
+        -> (address, dest_offset, offset, size, kexit_info)
+    %u256_to_addr DUP1 %insert_accessed_addresses
+    // stack: cold_access, address, dest_offset, offset, size, kexit_info
+    PUSH @GAS_COLDACCOUNTACCESS_MINUS_WARMACCESS
+    MUL
+    PUSH @GAS_WARMACCESS
+    ADD
+    // stack: Gaccess, address, dest_offset, offset, size, kexit_info
 
-    %mload_context_metadata(@CTX_METADATA_RETURNDATA_SIZE)
-    // stack: total_size, kexit_info, dest_offset, offset, size
-    DUP4
-    // stack: offset, total_size, kexit_info, dest_offset, offset, size
-    GT %jumpi(wcopy_large_offset)
+    DUP5
+    // stack: size, Gaccess, address, dest_offset, offset, size, kexit_info
+    ISZERO %jumpi(sys_extcodecopy_empty)
+
+    // stack: Gaccess, address, dest_offset, offset, size, kexit_info
+    DUP5 %num_bytes_to_num_words %mul_const(@GAS_COPY) ADD
+    %stack (gas, address, dest_offset, offset, size, kexit_info) -> (gas, kexit_info, address, dest_offset, offset, size)
+    %charge_gas
+
+    %stack (kexit_info, address, dest_offset, offset, size) -> (dest_offset, size, kexit_info, address, dest_offset, offset, size)
+    %add_or_fault
+    // stack: expanded_num_bytes, kexit_info, address, dest_offset, offset, size
+    DUP1 %ensure_reasonable_offset
+    %update_mem_bytes
+
+    %stack (kexit_info, address, dest_offset, offset, size) ->
+        (address, 0, @SEGMENT_KERNEL_ACCOUNT_CODE, extcodecopy_contd, 0, kexit_info, dest_offset, offset, size)
+    %jump(load_code)
+
+sys_extcodecopy_empty:
+    %stack (Gaccess, address, dest_offset, offset, size, kexit_info) -> (Gaccess, kexit_info)
+    %charge_gas
+    EXIT_KERNEL
 
-    PUSH @SEGMENT_RETURNDATA
-    %mload_context_metadata(@CTX_METADATA_RETURNDATA_SIZE)
-    // stack: total_size, returndata_segment, kexit_info, dest_offset, offset, size
-    DUP6 DUP6 ADD
-    // stack: offset + size, total_size, returndata_segment, kexit_info, dest_offset, offset, size
-    LT %jumpi(wcopy_within_bounds)
-
-    %mload_context_metadata(@CTX_METADATA_RETURNDATA_SIZE)
-    // stack: total_size, returndata_segment, kexit_info, dest_offset, offset, size
-    DUP6 DUP6 ADD
-    // stack: offset + size, total_size, returndata_segment, kexit_info, dest_offset, offset, size
+extcodecopy_contd:
+    // stack: code_size, src_ctx, kexit_info, dest_offset, offset, size
+    %codecopy_after_checks(@SEGMENT_KERNEL_ACCOUNT_CODE)
+
+
+// The internal logic is similar to wcopy, but handles range overflow differently.
+// It is used for both CODECOPY and EXTCODECOPY.
+%macro codecopy_after_checks(segment)
+    // stack: total_size, src_ctx, kexit_info, dest_offset, offset, size
+    DUP1 DUP6
+    // stack: offset, total_size, total_size, src_ctx, kexit_info, dest_offset, offset, size
+    GT %jumpi(codecopy_large_offset)
+
+    PUSH $segment SWAP1
+    // stack: total_size, segment, src_ctx, kexit_info, dest_offset, offset, size
+    DUP1 DUP8 DUP8 ADD
+    // stack: offset + size, total_size, total_size, segment, src_ctx, kexit_info, dest_offset, offset, size
+    LT %jumpi(codecopy_within_bounds)
+
+    // stack: total_size, segment, src_ctx, kexit_info, dest_offset, offset, size
+    DUP7 DUP7 ADD
+    // stack: offset + size, total_size, segment, src_ctx, kexit_info, dest_offset, offset, size
     SUB // extra_size = offset + size - total_size
-    // stack: extra_size, returndata_segment, kexit_info, dest_offset, offset, size
-    DUP1 DUP7 SUB
-    // stack: copy_size = size - extra_size, extra_size, returndata_segment, kexit_info, dest_offset, offset, size
+    // stack: extra_size, segment, src_ctx, kexit_info, dest_offset, offset, size
+    DUP1 DUP8 SUB
+    // stack: copy_size = size - extra_size, extra_size, segment, src_ctx, kexit_info, dest_offset, offset, size
 
     // Compute the new dest_offset after actual copies, at which we will start padding with zeroes.
-    DUP1 DUP6 ADD
-    // stack: new_dest_offset, copy_size, extra_size, returndata_segment, kexit_info, dest_offset, offset, size
+    DUP1 DUP7 ADD
+    // stack: new_dest_offset, copy_size, extra_size, segment, src_ctx, kexit_info, dest_offset, offset, size
 
     GET_CONTEXT
-    %stack (context, new_dest_offset, copy_size, extra_size, returndata_segment, kexit_info, dest_offset, offset, size) ->
-        (context, @SEGMENT_MAIN_MEMORY, dest_offset, context, returndata_segment, offset, copy_size, wcopy_over_range, new_dest_offset, extra_size, kexit_info)
+    %stack (context, new_dest_offset, copy_size, extra_size, segment, src_ctx, kexit_info, dest_offset, offset, size) ->
+        (context, @SEGMENT_MAIN_MEMORY, dest_offset, src_ctx, segment, offset, copy_size, wcopy_large_offset, kexit_info, new_dest_offset, offset, extra_size)
     %jump(memcpy_bytes)
-
-returndatacopy_empty:
-    %stack (kexit_info, dest_offset, offset, size) -> (kexit_info)
-    EXIT_KERNEL
+%endmacro