[ewasm] Add i32.select/i64.select

libyul/backends/wasm/BinaryTransform.cpp

@@ -156,6 +156,8 @@ Opcode constOpcodeFor(ValueType _type)
 }
 
 static map<string, uint8_t> const builtins = {
+	{"i32.select", 0x1b},
+	{"i64.select", 0x1b},
 	{"i32.load", 0x28},
 	{"i64.load", 0x29},
 	{"i32.load8_s", 0x2c},

libyul/backends/wasm/WasmDialect.cpp

@@ -120,6 +120,10 @@ WasmDialect::WasmDialect()
 	addFunction("i32.drop", {i32}, {});
 	addFunction("i64.drop", {i64}, {});
 
+	// Select is also overloaded.
+	addFunction("i32.select", {i32, i32, i32}, {i32});
+	addFunction("i64.select", {i64, i64, i32}, {i64});
+
 	addFunction("nop", {}, {});
 	addFunction("unreachable", {}, {}, false);
 	m_functions["unreachable"_yulstring].sideEffects.storage = SideEffects::None;