vNxM.load_splat instructions (#2350)

Introduces a new instruction class, `SIMDLoad`. Implements encoding,
decoding, parsing, printing, and interpretation of the load and splat
instructions, including in the C and JS APIs. `v128.load` remains in
the `Load` instruction class for now because the interpreter code
expects a `Load` to be able to load any memory value type.

1 files changed, 15 insertions, 0 deletions

diff --git a/src/wasm/wasm-validator.cpp b/src/wasm/wasm-validator.cpp
index e64e2ef73..68002e4d2 100644
--- a/src/wasm/wasm-validator.cpp
+++ b/src/wasm/wasm-validator.cpp
@@ -276,6 +276,7 @@ public:
   void visitSIMDShuffle(SIMDShuffle* curr);
   void visitSIMDTernary(SIMDTernary* curr);
   void visitSIMDShift(SIMDShift* curr);
+  void visitSIMDLoad(SIMDLoad* curr);
   void visitMemoryInit(MemoryInit* curr);
   void visitDataDrop(DataDrop* curr);
   void visitMemoryCopy(MemoryCopy* curr);
@@ -1054,6 +1055,20 @@ void FunctionValidator::visitSIMDShift(SIMDShift* curr) {
     curr->shift->type, i32, curr, "expected shift amount to have type i32");
 }
 
+void FunctionValidator::visitSIMDLoad(SIMDLoad* curr) {
+  shouldBeTrue(
+    getModule()->memory.exists, curr, "Memory operations require a memory");
+  shouldBeTrue(
+    getModule()->features.hasSIMD(), curr, "SIMD operation (SIMD is disabled)");
+  shouldBeEqualOrFirstIsUnreachable(
+    curr->type, v128, curr, "load_splat must have type v128");
+  shouldBeEqualOrFirstIsUnreachable(
+    curr->ptr->type, i32, curr, "load_splat address must have type i32");
+  Type lane_t = curr->op == LoadSplatVec64x2 ? i64 : i32;
+  Index bytes = curr->getMemBytes();
+  validateAlignment(curr->align, lane_t, bytes, /*isAtomic=*/false, curr);
+}
+
 void FunctionValidator::visitMemoryInit(MemoryInit* curr) {
   shouldBeTrue(getModule()->features.hasBulkMemory(),
                curr,