implement calldatacopy

Signed-off-by: xermicus <cyrill@parity.io>

crates/llvm-context/src/eravm/evm/crypto.rs

@@ -9,12 +9,52 @@ use crate::eravm::Dependency;
 /// Translates the `sha3` instruction.
 ///
 pub fn sha3<'ctx, D>(
-    _context: &mut Context<'ctx, D>,
-    _offset: inkwell::values::IntValue<'ctx>,
-    _length: inkwell::values::IntValue<'ctx>,
+    context: &mut Context<'ctx, D>,
+    offset: inkwell::values::IntValue<'ctx>,
+    length: inkwell::values::IntValue<'ctx>,
 ) -> anyhow::Result<inkwell::values::BasicValueEnum<'ctx>>
 where
     D: Dependency + Clone,
 {
-    todo!()
+    let offset_casted = context.safe_truncate_int_to_i32(offset)?;
+    let heap_pointer = context.get_global(crate::eravm::GLOBAL_HEAP_MEMORY_POINTER)?;
+    let input_pointer = unsafe {
+        context.builder().build_gep(
+            context.byte_type(),
+            heap_pointer.value.as_pointer_value(),
+            &[offset_casted],
+            "heap_offset_via_gep",
+        )
+    }?;
+    let input_pointer_casted = context.builder().build_ptr_to_int(
+        input_pointer,
+        context.integer_type(32),
+        "input_pointer_casted",
+    )?;
+
+    let length_casted = context.safe_truncate_int_to_i32(length)?;
+
+    let output_pointer = context.build_alloca(context.field_type(), "output_pointer");
+    let output_pointer_casted = context.builder().build_ptr_to_int(
+        output_pointer.value,
+        context.integer_type(32),
+        "output_pointer_casted",
+    )?;
+
+    let function = context
+        .module()
+        .get_function("hash_keccak_256")
+        .expect("is declared");
+
+    context.builder().build_call(
+        function,
+        &[
+            input_pointer_casted.into(),
+            length_casted.into(),
+            output_pointer_casted.into(),
+        ],
+        "call_seal_hash_keccak_256",
+    )?;
+
+    Ok(context.build_byte_swap(context.build_load(output_pointer, "sha3_output")?))
 }