diff --git a/src/dec/tree_dec.c b/src/dec/tree_dec.c
index 24346059..8093e78b 100644
--- a/src/dec/tree_dec.c
+++ b/src/dec/tree_dec.c
@@ -16,7 +16,8 @@
 #include "src/utils/bit_reader_inl_utils.h"
 
 #if !defined(USE_GENERIC_TREE)
-#if !defined(__arm__) && !defined(_M_ARM) && !WEBP_AARCH64
+#if !defined(__arm__) && !defined(_M_ARM) && !WEBP_AARCH64 && \
+    !defined(__wasm__)
 // using a table is ~1-2% slower on ARM. Prefer the coded-tree approach then.
 #define USE_GENERIC_TREE 1   // ALTERNATE_CODE
 #else
diff --git a/src/utils/bit_reader_utils.c b/src/utils/bit_reader_utils.c
index a26557aa..2707420f 100644
--- a/src/utils/bit_reader_utils.c
+++ b/src/utils/bit_reader_utils.c
@@ -124,7 +124,8 @@ int32_t VP8GetSignedValue(VP8BitReader* const br, int bits,
 
 #if defined(__arm__) || defined(_M_ARM) || WEBP_AARCH64 || \
     defined(__i386__) || defined(_M_IX86) || \
-    defined(__x86_64__) || defined(_M_X64)
+    defined(__x86_64__) || defined(_M_X64) || \
+    defined(__wasm__)
 #define VP8L_USE_FAST_LOAD
 #endif
 
diff --git a/src/utils/bit_reader_utils.h b/src/utils/bit_reader_utils.h
index 25ff31e5..b41a7881 100644
--- a/src/utils/bit_reader_utils.h
+++ b/src/utils/bit_reader_utils.h
@@ -69,6 +69,8 @@ extern "C" {
 #define BITS 56
 #elif defined(__mips__)                        // MIPS
 #define BITS 24
+#elif defined(__wasm__)                        // WASM
+#define BITS 56
 #else                                          // reasonable default
 #define BITS 24
 #endif