[llvm] [AArch64] Add lowering for `@llvm.experimental.vector.compress` (PR #101015)

[David Green via llvm-commits]

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@@ -0,0 +1,496 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -mtriple=aarch64 -mattr=+sve < %s | FileCheck %s
+
+define <vscale x 2 x i8> @test_compress_nxv2i8(<vscale x 2 x i8> %vec, <vscale x 2 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv2i8:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.d, p0, z0.d
+; CHECK-NEXT:    ret
+    %out = call <vscale x 2 x i8> @llvm.experimental.vector.compress(<vscale x 2 x i8> %vec, <vscale x 2 x i1> %mask, <vscale x 2 x i8> undef)
+    ret <vscale x 2 x i8> %out
+}
+
+define <vscale x 2 x i16> @test_compress_nxv2i16(<vscale x 2 x i16> %vec, <vscale x 2 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv2i16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.d, p0, z0.d
+; CHECK-NEXT:    ret
+    %out = call <vscale x 2 x i16> @llvm.experimental.vector.compress(<vscale x 2 x i16> %vec, <vscale x 2 x i1> %mask, <vscale x 2 x i16> undef)
+    ret <vscale x 2 x i16> %out
+}
+
+define <vscale x 2 x i32> @test_compress_nxv2i32(<vscale x 2 x i32> %vec, <vscale x 2 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv2i32:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.d, p0, z0.d
+; CHECK-NEXT:    ret
+    %out = call <vscale x 2 x i32> @llvm.experimental.vector.compress(<vscale x 2 x i32> %vec, <vscale x 2 x i1> %mask, <vscale x 2 x i32> undef)
+    ret <vscale x 2 x i32> %out
+}
+
+define <vscale x 2 x i64> @test_compress_nxv2i64(<vscale x 2 x i64> %vec, <vscale x 2 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv2i64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.d, p0, z0.d
+; CHECK-NEXT:    ret
+    %out = call <vscale x 2 x i64> @llvm.experimental.vector.compress(<vscale x 2 x i64> %vec, <vscale x 2 x i1> %mask, <vscale x 2 x i64> undef)
+    ret <vscale x 2 x i64> %out
+}
+
+define <vscale x 2 x float> @test_compress_nxv2f32(<vscale x 2 x float> %vec, <vscale x 2 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv2f32:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.d, p0, z0.d
+; CHECK-NEXT:    ret
+    %out = call <vscale x 2 x float> @llvm.experimental.vector.compress(<vscale x 2 x float> %vec, <vscale x 2 x i1> %mask, <vscale x 2 x float> undef)
+    ret <vscale x 2 x float> %out
+}
+
+define <vscale x 2 x double> @test_compress_nxv2f64(<vscale x 2 x double> %vec, <vscale x 2 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv2f64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.d, p0, z0.d
+; CHECK-NEXT:    ret
+    %out = call <vscale x 2 x double> @llvm.experimental.vector.compress(<vscale x 2 x double> %vec, <vscale x 2 x i1> %mask, <vscale x 2 x double> undef)
+    ret <vscale x 2 x double> %out
+}
+
+define <vscale x 4 x i8> @test_compress_nxv4i8(<vscale x 4 x i8> %vec, <vscale x 4 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv4i8:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.s, p0, z0.s
+; CHECK-NEXT:    ret
+    %out = call <vscale x 4 x i8> @llvm.experimental.vector.compress(<vscale x 4 x i8> %vec, <vscale x 4 x i1> %mask, <vscale x 4 x i8> undef)
+    ret <vscale x 4 x i8> %out
+}
+
+define <vscale x 4 x i16> @test_compress_nxv4i16(<vscale x 4 x i16> %vec, <vscale x 4 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv4i16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.s, p0, z0.s
+; CHECK-NEXT:    ret
+    %out = call <vscale x 4 x i16> @llvm.experimental.vector.compress(<vscale x 4 x i16> %vec, <vscale x 4 x i1> %mask, <vscale x 4 x i16> undef)
+    ret <vscale x 4 x i16> %out
+}
+
+define <vscale x 4 x i32> @test_compress_nxv4i32(<vscale x 4 x i32> %vec, <vscale x 4 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv4i32:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.s, p0, z0.s
+; CHECK-NEXT:    ret
+    %out = call <vscale x 4 x i32> @llvm.experimental.vector.compress(<vscale x 4 x i32> %vec, <vscale x 4 x i1> %mask, <vscale x 4 x i32> undef)
+    ret <vscale x 4 x i32> %out
+}
+
+define <vscale x 4 x float> @test_compress_nxv4f32(<vscale x 4 x float> %vec, <vscale x 4 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv4f32:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    compact z0.s, p0, z0.s
+; CHECK-NEXT:    ret
+    %out = call <vscale x 4 x float> @llvm.experimental.vector.compress(<vscale x 4 x float> %vec, <vscale x 4 x i1> %mask, <vscale x 4 x float> undef)
+    ret <vscale x 4 x float> %out
+}
+
+define <vscale x 8 x i8> @test_compress_nxv8i8(<vscale x 8 x i8> %vec, <vscale x 8 x i1> %mask) {
+; CHECK-LABEL: test_compress_nxv8i8:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    str x29, [sp, #-16]! // 8-byte Folded Spill
+; CHECK-NEXT:    addvl sp, sp, #-1
+; CHECK-NEXT:    .cfi_escape 0x0f, 0x0c, 0x8f, 0x00, 0x11, 0x10, 0x22, 0x11, 0x08, 0x92, 0x2e, 0x00, 0x1e, 0x22 // sp + 16 + 8 * VG
+; CHECK-NEXT:    .cfi_offset w29, -16
+; CHECK-NEXT:    ptrue p1.h
+; CHECK-NEXT:    st1b { z0.h }, p0, [sp, #1, mul vl]
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davemgreen wrote:

I'm not sure if this is doing a compress.

https://github.com/llvm/llvm-project/pull/101015