[WebAssembly] Custom lower i64x2 constant shifts to avoid wrap
Summary: Depends on D53057.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53251
llvm-svn: 344825
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
index 95c8726..0b09da7 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
@@ -515,6 +515,19 @@
def : Pat<(v2i64 (shifts[0] (v2i64 V128:$vec), (v2i64 (splat2 I64:$x)))),
(v2i64 (shifts[1] (v2i64 V128:$vec), (I32_WRAP_I64 I64:$x)))>;
+// 2xi64 shifts with constant shift amounts are custom lowered to avoid wrapping
+def wasm_shift_t : SDTypeProfile<1, 2,
+ [SDTCisVec<0>, SDTCisSameAs<0, 1>, SDTCisVT<2, i32>]
+>;
+def wasm_shl : SDNode<"WebAssemblyISD::VEC_SHL", wasm_shift_t>;
+def wasm_shr_s : SDNode<"WebAssemblyISD::VEC_SHR_S", wasm_shift_t>;
+def wasm_shr_u : SDNode<"WebAssemblyISD::VEC_SHR_U", wasm_shift_t>;
+foreach shifts = [[wasm_shl, SHL_v2i64],
+ [wasm_shr_s, SHR_S_v2i64],
+ [wasm_shr_u, SHR_U_v2i64]] in
+def : Pat<(v2i64 (shifts[0] (v2i64 V128:$vec), I32:$x)),
+ (v2i64 (shifts[1] (v2i64 V128:$vec), I32:$x))>;
+
//===----------------------------------------------------------------------===//
// Bitwise operations
//===----------------------------------------------------------------------===//