[WebAssembly] Add builtin and intrinsic for v8x16.swizzle
Summary:
This clang builtin and corresponding LLVM intrinsic are necessary to
expose the exact semantics of the underlying WebAssembly instruction
to users. LLVM produces a poison value if the dynamic swizzle indices
are greater than the vector size, but the WebAssembly instruction sets
the corresponding output lane to zero. Users who depend on this
behavior can safely use this builtin.
Depends on D68527.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D68531
llvm-svn: 374189
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
index 16549f3..fc5d73d 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
@@ -278,12 +278,16 @@
// Swizzle lanes: v8x16.swizzle
def wasm_swizzle_t : SDTypeProfile<1, 2, []>;
def wasm_swizzle : SDNode<"WebAssemblyISD::SWIZZLE", wasm_swizzle_t>;
+let Predicates = [HasUnimplementedSIMD128] in
defm SWIZZLE :
SIMD_I<(outs V128:$dst), (ins V128:$src, V128:$mask), (outs), (ins),
[(set (v16i8 V128:$dst),
(wasm_swizzle (v16i8 V128:$src), (v16i8 V128:$mask)))],
"v8x16.swizzle\t$dst, $src, $mask", "v8x16.swizzle", 192>;
+def : Pat<(int_wasm_swizzle (v16i8 V128:$src), (v16i8 V128:$mask)),
+ (SWIZZLE V128:$src, V128:$mask)>;
+
// Create vector with identical lanes: splat
def splat2 : PatFrag<(ops node:$x), (build_vector node:$x, node:$x)>;
def splat4 : PatFrag<(ops node:$x), (build_vector