[WebAssembly] v8x16.swizzle and rewrite BUILD_VECTOR lowering
Summary:
Adds the new v8x16.swizzle SIMD instruction as specified at
https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#swizzling-using-variable-indices.
In addition to adding swizzles as a candidate lowering in
LowerBUILD_VECTOR, also rewrites and simplifies the lowering to
minimize the number of replace_lanes necessary rather than trying to
minimize code size. This leads to more uses of v128.const instead of
splats, which is expected to increase performance.
The new code will be easier to tune once V8 implements all the vector
construction operations, and it will also be easier to add new
candidate instructions in the future if necessary.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68527
llvm-svn: 374188
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
index a9966af..16549f3 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
@@ -275,6 +275,15 @@
(i32 LaneIdx32:$mE), (i32 LaneIdx32:$mF)))>;
}
+// Swizzle lanes: v8x16.swizzle
+def wasm_swizzle_t : SDTypeProfile<1, 2, []>;
+def wasm_swizzle : SDNode<"WebAssemblyISD::SWIZZLE", wasm_swizzle_t>;
+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, $mask", "v8x16.swizzle", 192>;
+
// Create vector with identical lanes: splat
def splat2 : PatFrag<(ops node:$x), (build_vector node:$x, node:$x)>;
def splat4 : PatFrag<(ops node:$x), (build_vector