feat: add most basic simd instructions

Signed-off-by: Henry Gressmann <mail@henrygressmann.de>

2 files changed, 6 insertions, 5 deletions

diff --git a/crates/parser/src/conversion.rs b/crates/parser/src/conversion.rs
index 86548d6..a4e3b35 100644
--- a/crates/parser/src/conversion.rs
+++ b/crates/parser/src/conversion.rs
@@ -261,6 +261,7 @@ pub(crate) fn process_const_operators(ops: OperatorsReader<'_>) -> Result<ConstI
         wasmparser::Operator::I64Const { value } => Ok(ConstInstruction::I64Const(*value)),
         wasmparser::Operator::F32Const { value } => Ok(ConstInstruction::F32Const(f32::from_bits(value.bits()))),
         wasmparser::Operator::F64Const { value } => Ok(ConstInstruction::F64Const(f64::from_bits(value.bits()))),
+        wasmparser::Operator::V128Const { value } => Ok(ConstInstruction::V128Const(value.i128())),
         wasmparser::Operator::GlobalGet { global_index } => Ok(ConstInstruction::GlobalGet(*global_index)),
         op => Err(crate::ParseError::UnsupportedOperator(format!("Unsupported const instruction: {op:?}"))),
     }
diff --git a/crates/parser/src/visit.rs b/crates/parser/src/visit.rs
index 2830d3a..270f6c6 100644
--- a/crates/parser/src/visit.rs
+++ b/crates/parser/src/visit.rs
@@ -111,7 +111,7 @@ macro_rules! define_mem_operands_simd_lane {
 pub(crate) struct FunctionBuilder<R: WasmModuleResources> {
     validator: FuncValidator<R>,
     instructions: Vec<Instruction>,
-    v128_constants: Vec<u128>,
+    v128_constants: Vec<i128>,
     label_ptrs: Vec<usize>,
     local_addr_map: Vec<u32>,
     errors: Vec<crate::ParseError>,
@@ -530,12 +530,12 @@ impl<R: WasmModuleResources> wasmparser::VisitSimdOperator<'_> for FunctionBuild
     }
 
     fn visit_i8x16_shuffle(&mut self, lanes: [u8; 16]) -> Self::Output {
-        self.v128_constants.push(u128::from_le_bytes(lanes));
-        self.instructions.push(Instruction::I8x16Shuffle(self.v128_constants.len() as u32 - 1));
+        self.instructions.push(Instruction::I8x16Shuffle(self.v128_constants.len() as u32));
+        self.v128_constants.push(i128::from_le_bytes(lanes));
     }
 
     fn visit_v128_const(&mut self, value: wasmparser::V128) -> Self::Output {
-        self.v128_constants.push(value.i128() as u128);
-        self.instructions.push(Instruction::V128Const(self.v128_constants.len() as u32 - 1));
+        self.instructions.push(Instruction::V128Const(self.v128_constants.len() as u32));
+        self.v128_constants.push(value.i128());
     }
 }