diff --git a/evm/src/cpu/kernel/asm/memory/memcpy.asm b/evm/src/cpu/kernel/asm/memory/memcpy.asm index 108b7c6f..e737dc33 100644 --- a/evm/src/cpu/kernel/asm/memory/memcpy.asm +++ b/evm/src/cpu/kernel/asm/memory/memcpy.asm @@ -57,6 +57,17 @@ memcpy_finish: // Similar logic to memcpy, but optimized for copying sequences of bytes. global memcpy_bytes: // stack: DST, SRC, count, retdest + + // Handle empty case + DUP7 + // stack: count, DST, SRC, count, retdest + ISZERO + // stack: count == 0, DST, SRC, count, retdest + %jumpi(memcpy_bytes_empty) + + // stack: DST, SRC, count, retdest + + // Handle small case DUP7 // stack: count, DST, SRC, count, retdest %lt_const(0x20) @@ -119,6 +130,12 @@ memcpy_bytes_finish: // stack: retdest JUMP +memcpy_bytes_empty: + // stack: DST, SRC, 0, retdest + %pop7 + // stack: retdest + JUMP + %macro memcpy_bytes %stack (dst: 3, src: 3, count) -> (dst, src, count, %%after) %jump(memcpy_bytes) diff --git a/evm/src/cpu/kernel/asm/memory/memset.asm b/evm/src/cpu/kernel/asm/memory/memset.asm index c0bad482..4c2e363b 100644 --- a/evm/src/cpu/kernel/asm/memory/memset.asm +++ b/evm/src/cpu/kernel/asm/memory/memset.asm @@ -2,12 +2,22 @@ // DST = (dst_ctx, dst_segment, dst_addr). // This tuple definition is used for brevity in the stack comments below. global memset: + // Handle empty case + DUP7 + // stack: count, DST, count, retdest + ISZERO + // stack: count == 0, DST, count, retdest + %jumpi(memset_bytes_empty) + // stack: DST, count, retdest + + // Handle small case DUP4 // stack: count, DST, count, retdest %lt_const(0x20) // stack: count < 32, DST, count, retdest %jumpi(memset_finish) + // stack: DST, count, retdest PUSH 32 PUSH 0 @@ -43,3 +53,9 @@ memset_finish: %pop4 // stack: retdest JUMP + +memset_bytes_empty: + // stack: DST, 0, retdest + %pop4 + // stack: retdest + JUMP