implement the value opcode

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

crates/llvm-context/src/eravm/const.rs

@@ -3,7 +3,7 @@
 //!
 
 /// The LLVM framework version.
-pub const LLVM_VERSION: semver::Version = semver::Version::new(15, 0, 4);
+pub const LLVM_VERSION: semver::Version = semver::Version::new(18, 1, 4);
 
 /// The EraVM version.
 pub const ZKEVM_VERSION: semver::Version = semver::Version::new(1, 3, 2);

crates/llvm-context/src/eravm/context/mod.rs

@@ -1480,6 +1480,12 @@ where
         self.llvm.custom_width_int_type(crate::eravm::XLEN as u32)
     }
 
+    /// Returns the runtime value width sized type.
+    pub fn value_type(&self) -> inkwell::types::IntType<'ctx> {
+        self.llvm
+            .custom_width_int_type(revive_common::BIT_LENGTH_VALUE as u32)
+    }
+
     ///
     /// Returns the default field type.
     ///

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

@@ -28,7 +28,43 @@ pub fn value<'ctx, D>(
 where
     D: Dependency + Clone,
 {
-    Ok(context.integer_const(256, 0).as_basic_value_enum())
+    let output_pointer = context.build_alloca(context.value_type(), "output_pointer");
+    let output_pointer_casted = context.builder().build_ptr_to_int(
+        output_pointer.value,
+        context.xlen_type(),
+        "output_pointer_casted",
+    )?;
+
+    let output_length_pointer = context.build_alloca(context.xlen_type(), "output_len_pointer");
+    let output_length_pointer_casted = context.builder().build_ptr_to_int(
+        output_length_pointer.value,
+        context.xlen_type(),
+        "output_pointer_casted",
+    )?;
+    context.build_store(
+        output_length_pointer,
+        context.integer_const(crate::eravm::XLEN, revive_common::BYTE_LENGTH_VALUE as u64),
+    )?;
+
+    context.builder().build_call(
+        context
+            .module()
+            .get_function("value_transferred")
+            .expect("is declared"),
+        &[
+            output_pointer_casted.into(),
+            output_length_pointer_casted.into(),
+        ],
+        "call_seal_value_transferred",
+    )?;
+
+    let value = context.build_load(output_pointer, "transferred_value")?;
+    let value_extended = context.builder().build_int_z_extend(
+        value.into_int_value(),
+        context.field_type(),
+        "transferred_value_extended",
+    )?;
+    Ok(value_extended.as_basic_value_enum())
 }
 
 ///