[llvm] [WebAssembly] Add pattern for relaxed laneselect (from bitselect simd) (PR #163807)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-webassembly

Author: Jasmine Tang (badumbatish)

<details>
<summary>Changes</summary>

Related to #<!-- -->55932

---
Full diff: https://github.com/llvm/llvm-project/pull/163807.diff


2 Files Affected:

- (modified) llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td (+7) 
- (added) llvm/test/CodeGen/WebAssembly/simd-relaxed-laneselect.ll (+79) 


``````````diff
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
index 49af78bce68c3..39f18b969d221 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td
@@ -1662,6 +1662,13 @@ multiclass SIMDLANESELECT<Vec vec, bits<32> op> {
                 (vec.vt V128:$a), (vec.vt V128:$b), (vec.vt V128:$c)))],
               vec.prefix#".relaxed_laneselect\t$dst, $a, $b, $c",
               vec.prefix#".relaxed_laneselect", op>;
+
+  let AddedComplexity = 1 in {
+    def : Pat<(vec.vt (int_wasm_bitselect
+                (vec.vt V128:$a), (vec.vt V128:$b), (vec.vt V128:$c))),
+              (!cast<Instruction>("LANESELECT_"#vec) V128:$a, V128:$b, V128:$c)>,
+              Requires<[HasRelaxedSIMD]>;
+  }
 }
 
 defm "" : SIMDLANESELECT<I8x16, 0x109>;
diff --git a/llvm/test/CodeGen/WebAssembly/simd-relaxed-laneselect.ll b/llvm/test/CodeGen/WebAssembly/simd-relaxed-laneselect.ll
new file mode 100644
index 0000000000000..b63e9e166b8d2
--- /dev/null
+++ b/llvm/test/CodeGen/WebAssembly/simd-relaxed-laneselect.ll
@@ -0,0 +1,79 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+
+; RUN: llc < %s -verify-machineinstrs -wasm-disable-explicit-locals -wasm-keep-registers -mattr=+simd128,+relaxed-simd | FileCheck %s --check-prefix=RELAXED
+; RUN: llc < %s -verify-machineinstrs -wasm-disable-explicit-locals -wasm-keep-registers -mattr=+simd128               | FileCheck %s --check-prefix=SIMD
+
+; Test that bitselect intrinsic lowers to relaxed_laneselect when relaxed-simd is enabled
+
+target triple = "wasm32-unknown-unknown"
+
+define <16 x i8> @bitselect_to_laneselect_v16i8(<16 x i8> %a, <16 x i8> %b, <16 x i8> %c) {
+; RELAXED-LABEL: bitselect_to_laneselect_v16i8:
+; RELAXED:         .functype bitselect_to_laneselect_v16i8 (v128, v128, v128) -> (v128)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    i8x16.relaxed_laneselect $push0=, $0, $1, $2
+; RELAXED-NEXT:    # fallthrough-return
+;
+; SIMD-LABEL: bitselect_to_laneselect_v16i8:
+; SIMD:         .functype bitselect_to_laneselect_v16i8 (v128, v128, v128) -> (v128)
+; SIMD-NEXT:  # %bb.0:
+; SIMD-NEXT:    v128.bitselect $push0=, $0, $1, $2
+; SIMD-NEXT:    # fallthrough-return
+  %res = call <16 x i8> @llvm.wasm.bitselect.v16i8(<16 x i8> %a, <16 x i8> %b, <16 x i8> %c)
+  ret <16 x i8> %res
+}
+
+define <8 x i16> @bitselect_to_laneselect_v8i16(<8 x i16> %a, <8 x i16> %b, <8 x i16> %c) {
+; RELAXED-LABEL: bitselect_to_laneselect_v8i16:
+; RELAXED:         .functype bitselect_to_laneselect_v8i16 (v128, v128, v128) -> (v128)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    i16x8.relaxed_laneselect $push0=, $0, $1, $2
+; RELAXED-NEXT:    # fallthrough-return
+;
+; SIMD-LABEL: bitselect_to_laneselect_v8i16:
+; SIMD:         .functype bitselect_to_laneselect_v8i16 (v128, v128, v128) -> (v128)
+; SIMD-NEXT:  # %bb.0:
+; SIMD-NEXT:    v128.bitselect $push0=, $0, $1, $2
+; SIMD-NEXT:    # fallthrough-return
+  %res = call <8 x i16> @llvm.wasm.bitselect.v8i16(<8 x i16> %a, <8 x i16> %b, <8 x i16> %c)
+  ret <8 x i16> %res
+}
+
+define <4 x i32> @bitselect_to_laneselect_v4i32(<4 x i32> %a, <4 x i32> %b, <4 x i32> %c) {
+; RELAXED-LABEL: bitselect_to_laneselect_v4i32:
+; RELAXED:         .functype bitselect_to_laneselect_v4i32 (v128, v128, v128) -> (v128)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    i32x4.relaxed_laneselect $push0=, $0, $1, $2
+; RELAXED-NEXT:    # fallthrough-return
+;
+; SIMD-LABEL: bitselect_to_laneselect_v4i32:
+; SIMD:         .functype bitselect_to_laneselect_v4i32 (v128, v128, v128) -> (v128)
+; SIMD-NEXT:  # %bb.0:
+; SIMD-NEXT:    v128.bitselect $push0=, $0, $1, $2
+; SIMD-NEXT:    # fallthrough-return
+  %res = call <4 x i32> @llvm.wasm.bitselect.v4i32(<4 x i32> %a, <4 x i32> %b, <4 x i32> %c)
+  ret <4 x i32> %res
+}
+
+define <2 x i64> @bitselect_to_laneselect_v2i64(<2 x i64> %a, <2 x i64> %b, <2 x i64> %c) {
+; RELAXED-LABEL: bitselect_to_laneselect_v2i64:
+; RELAXED:         .functype bitselect_to_laneselect_v2i64 (v128, v128, v128) -> (v128)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    i64x2.relaxed_laneselect $push0=, $0, $1, $2
+; RELAXED-NEXT:    # fallthrough-return
+;
+; SIMD-LABEL: bitselect_to_laneselect_v2i64:
+; SIMD:         .functype bitselect_to_laneselect_v2i64 (v128, v128, v128) -> (v128)
+; SIMD-NEXT:  # %bb.0:
+; SIMD-NEXT:    v128.bitselect $push0=, $0, $1, $2
+; SIMD-NEXT:    # fallthrough-return
+  %res = call <2 x i64> @llvm.wasm.bitselect.v2i64(<2 x i64> %a, <2 x i64> %b, <2 x i64> %c)
+  ret <2 x i64> %res
+}
+
+
+
+declare <16 x i8> @llvm.wasm.bitselect.v16i8(<16 x i8>, <16 x i8>, <16 x i8>)
+declare <8 x i16> @llvm.wasm.bitselect.v8i16(<8 x i16>, <8 x i16>, <8 x i16>)
+declare <4 x i32> @llvm.wasm.bitselect.v4i32(<4 x i32>, <4 x i32>, <4 x i32>)
+declare <2 x i64> @llvm.wasm.bitselect.v2i64(<2 x i64>, <2 x i64>, <2 x i64>)

``````````

</details>


https://github.com/llvm/llvm-project/pull/163807