Environment

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ADDRESS

Original EVM instruction.

This value is fetched with a native EraVM instruction: context.this.

LLVM IR

The LLVM IR generator code is common for Yul and EVMLA representations.

BALANCE

Original EVM instruction.

System Contract

This information is requested a System Contract called L2BaseToken.

On how the System Contract is called, see this section.

LLVM IR

The LLVM IR generator code is common for Yul and EVMLA representations.

The request to the System Contract is done via the SystemRequest runtime function.

ORIGIN

Original EVM instruction.

System Contract

This information is requested a System Contract called SystemContext.

On how the System Contract is called, see this section.

LLVM IR

The LLVM IR generator code is common for Yul and EVMLA representations.

The request to the System Contract is done via the SystemRequest runtime function.

CALLER

Original EVM instruction.

This value is fetched with a native EraVM instruction: context.caller.

LLVM IR

The LLVM IR generator code is common for Yul and EVMLA representations.

CALLVALUE

Original EVM instruction.

This value is fetched with a native EraVM instruction: context.get_context_u128.

LLVM IR

The LLVM IR generator code is common for Yul and EVMLA representations.

CALLDATALOAD

Original EVM instruction.

Calldata is accessed with a generic memory access instruction, but the memory chunk itself is a reference to the calling contract's heap. A fat pointer to the parent contract is passed via ABI using registers.

Then, the pointer is saved to a global stack variable accessible from anywhere in the contract.

LLVM IR

@ptr_calldata = private unnamed_addr global ptr addrspace(3) null                   ; global variable declaration
...
store ptr addrspace(3) %0, ptr @ptr_calldata, align 32                              ; saving the pointer from `r1` to the global variable
...
%calldata_pointer = load ptr addrspace(3), ptr @ptr_calldata, align 32              ; loading the pointer from the global variable to `calldata_pointer`
%calldata_value = load i256, ptr addrspace(3) %calldata_pointer, align 32           ; loading the value from the calldata pointer

The LLVM IR generator code is common for Yul and EVMLA representations.

EraVM Assembly

ptr.add r1, r0, stack[@ptr_calldata]                                                ; saving the pointer from `r1` to the global variable
...
ptr.add stack[@ptr_calldata], r0, r1                                                ; loading the pointer from the global variable to `r1`
ld      r1, r1                                                                      ; loading the value to `r1`

• EraVM instruction: ptr.add

• EraVM fat pointers

• EraVM memory forwarding mechanism

CALLDATASIZE

Original EVM instruction.

Calldata size is stored in the fat pointer passed from the parent contract (see CALLDATALOAD).

The size value can be extracted with bitwise operations as illustrated below.

LLVM IR

@calldatasize = private unnamed_addr global i256 0                                  ; global variable declaration
...
%abi_pointer_value = ptrtoint ptr addrspace(3) %0 to i256                           ; converting the pointer to an integer
%abi_pointer_value_shifted = lshr i256 %abi_pointer_value, 96                       ; shifting the integer right 96 bits
%abi_length_value = and i256 %abi_pointer_value_shifted, 4294967295                 ; keeping the lowest 32 bits of the integer
store i256 %abi_length_value, ptr @calldatasize, align 32                           ; saving the value to the global variable

The LLVM IR generator code is common for Yul and EVMLA representations.

EraVM Assembly

ptr.add r1, r0, stack[@ptr_calldata]                                                ; saving the pointer from `r1` to the global variable
shr.s   96, r1, r1                                                                  ; shifting the integer right 96 bits
and     @CPI0_0[0], r1, stack[@calldatasize]                                        ; keeping the lowest 32 bits of the integer, saving the value to the global variable
...
CPI0_0:
    .cell 4294967295

• EraVM instruction: ptr.add

• EraVM fat pointers

• EraVM memory forwarding mechanism

CALLDATACOPY

Original EVM instruction.

Unlike on EVM, on EraVM it is a simple loop over CALLDATALOAD).

LLVM IR

; loading the pointer from the global variable to `calldata_pointer`
%calldata_pointer = load ptr addrspace(3), ptr @ptr_calldata, align 32
; shifting the pointer by 122 bytes
%calldata_source_pointer = getelementptr i8, ptr addrspace(3) %calldata_pointer, i256 122
; copying 64 bytes from calldata at offset 122 to the heap at offset 128
call void @llvm.memcpy.p1.p3.i256(ptr addrspace(1) align 1 inttoptr (i256 128 to ptr addrspace(1)), ptr addrspace(3) align 1 %calldata_source_pointer, i256 64, i1 false)

The LLVM IR generator code is common for Yul and EVMLA representations.

EraVM Assembly

.BB0_3:
    shl.s   5, r2, r3           ; shifting the offset by 32
    ptr.add r1, r3, r4          ; adding the offset to the calldata pointer
    ld      r4, r4              ; reading the calldata value
    add     128, r3, r3         ; adding the offset to the heap pointer
    st.1    r3, r4              ; writing the calldata value to the heap
    add     1, r2, r2           ; incrementing the offset
    sub.s!  2, r2, r3           ; checking the bounds
    jump.lt @.BB0_3             ; loop continuation branching

• EraVM instruction: ptr.add

• EraVM fat pointers

• EraVM memory forwarding mechanism

CODECOPY

Original EVM instruction.

See the EraVM docs.

The LLVM IR generator code.

CODESIZE

Original EVM instruction.

See the EraVM docs.

The LLVM IR generator code.

GASPRICE

Original EVM instruction.

System Contract

This information is requested a System Contract called SystemContext.

On how the System Contract is called, see this section.

LLVM IR

The LLVM IR generator code is common for Yul and EVMLA representations.

The request to the System Contract is done via the SystemRequest runtime function.

EXTCODESIZE

Original EVM instruction.

System Contract

This information is requested a System Contract called AccountCodeStorage.

On how the System Contract is called, see this section.

LLVM IR

The LLVM IR generator code is common for Yul and EVMLA representations.

The request to the System Contract is done via the SystemRequest runtime function.

EXTCODECOPY

Original EVM instruction.

Not supported. Triggers a compile-time error.

RETURNDATASIZE

Original EVM instruction.

Return data size is read from the fat pointer returned from the child contract.

The size value can be extracted with bitwise operations as illustrated below.

LLVM IR

%contract_call_external = tail call { ptr addrspace(3), i1 } @__farcall(i256 0, i256 0, i256 undef, i256 undef, i256 undef, i256 undef, i256 undef, i256 undef, i256 undef, i256 undef, i256 undef, i256 undef)
%contract_call_external_result_abi_data = extractvalue { ptr addrspace(3), i1 } %contract_call_external, 0
%contract_call_memcpy_from_child_pointer_casted = ptrtoint ptr addrspace(3) %contract_call_external_result_abi_data to i256
%contract_call_memcpy_from_child_return_data_size_shifted = lshr i256 %contract_call_memcpy_from_child_pointer_casted, 96
%contract_call_memcpy_from_child_return_data_size_truncated = and i256 %contract_call_memcpy_from_child_return_data_size_shifted, 4294967295

The LLVM IR generator code is common for Yul and EVMLA representations.

EraVM Assembly

near_call       r0, @__farcall, @DEFAULT_UNWIND                 ; calling a child contract
shr.s   96, r1, r1                                              ; shifting the pointer value right 96 bits
and     @CPI0_1[0], r1, r1                                      ; keeping the lowest 32 bits of the pointer value
...
CPI0_1:
    .cell 4294967295

EraVM instruction: call

RETURNDATACOPY

Original EVM instruction.

Unlike on EVM, on EraVM it is a simple loop over memory operations on 256-bit values.

LLVM IR

; loading the pointer from the global variable to `return_data_pointer`
%return_data_pointer = load ptr addrspace(3), ptr @ptr_return_data, align 32
; shifting the pointer by 122 bytes
%return_data_source_pointer = getelementptr i8, ptr addrspace(3) %return_data_pointer, i256 122
; copying 64 bytes from return data at offset 122 to the heap at offset 128
call void @llvm.memcpy.p1.p3.i256(ptr addrspace(1) align 1 inttoptr (i256 128 to ptr addrspace(1)), ptr addrspace(3) align 1 %return_data_source_pointer, i256 64, i1 false)

The LLVM IR generator code is common for Yul and EVMLA representations.

EraVM Assembly

.BB0_3:
    shl.s   5, r2, r3           ; shifting the offset by 32
    ptr.add r1, r3, r4          ; adding the offset to the return data pointer
    ld      r4, r4              ; reading the return data value
    add     128, r3, r3         ; adding the offset to the heap pointer
    st.1    r3, r4              ; writing the return data value to the heap
    add     1, r2, r2           ; incrementing the offset
    sub.s!  2, r2, r3           ; checking the bounds
    jump.lt @.BB0_3             ; loop continuation branching

• EraVM instruction: jump

• EraVM instruction predication

EXTCODEHASH

Original EVM instruction.

System Contract

This information is requested a System Contract called AccountCodeStorage.

On how the System Contract is called, see this section.

LLVM IR

The LLVM IR generator code is common for Yul and EVMLA representations.

The request to the System Contract is done via the SystemRequest runtime function.