[llvm] [AArch64] Lower masked.expandload intrinsic using SVE2p2/SME2p2 EXPAND (PR #190999)

[Paul Walker via llvm-commits]

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@@ -0,0 +1,89 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=aarch64--linux-gnu -mattr=+sve2p2 < %s | FileCheck %s
+; RUN: llc -mtriple=aarch64--linux-gnu -mattr=+sve -mattr=+sme2p2 < %s | FileCheck %s
+; RUN: llc -mtriple=aarch64--linux-gnu -mattr=+sve -mattr=+sme2p2 -force-streaming < %s | FileCheck %s
+
+define <vscale x 2 x i64> @test_expandload(ptr %base, <vscale x 2 x i64> %passthru, <vscale x 2 x i1> %pred) {
+; CHECK-LABEL: test_expandload:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cntp x8, p0, p0.d
+; CHECK-NEXT:    whilelo p1.d, xzr, x8
+; CHECK-NEXT:    ld1d { z1.d }, p1/z, [x0]
+; CHECK-NEXT:    expand z1.d, p0, z1.d
+; CHECK-NEXT:    mov z0.d, p0/m, z1.d
+; CHECK-NEXT:    ret
+  %res = call <vscale x 2 x i64> @llvm.masked.expandload(ptr align 1 %base, <vscale x 2 x i1> %pred, <vscale x 2 x i64> %passthru)
+  ret <vscale x 2 x i64> %res
+}
+
+define <vscale x 8 x float> @test_split_expandload(ptr %base, <vscale x 8 x float> %passthru, <vscale x 8 x i1> %pred) {
+; CHECK-LABEL: test_split_expandload:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    punpklo p1.h, p0.b
+; CHECK-NEXT:    punpkhi p0.h, p0.b
+; CHECK-NEXT:    cntp x8, p1, p1.s
+; CHECK-NEXT:    cntp x9, p0, p0.s
+; CHECK-NEXT:    whilelo p2.s, xzr, x8
+; CHECK-NEXT:    whilelo p3.s, xzr, x9
+; CHECK-NEXT:    ld1w { z2.s }, p2/z, [x0]
+; CHECK-NEXT:    ld1w { z3.s }, p3/z, [x0, x8, lsl #2]
+; CHECK-NEXT:    expand z2.s, p1, z2.s
+; CHECK-NEXT:    expand z3.s, p0, z3.s
+; CHECK-NEXT:    mov z0.s, p1/m, z2.s
+; CHECK-NEXT:    mov z1.s, p0/m, z3.s
+; CHECK-NEXT:    ret
+  %res = call <vscale x 8 x float> @llvm.masked.expandload(ptr align 1 %base, <vscale x 8 x i1> %pred, <vscale x 8 x float> %passthru)
+  ret <vscale x 8 x float> %res
+}
+
+define <vscale x 1 x i64> @test_promote_expandload(ptr %base, <vscale x 1 x i64> %passthru, <vscale x 1 x i1> %pred) {
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paulwalker-arm wrote:

The result/parameter types imply widening rather than promotion. Perhaps use `<vscale x 2 x i8>`?

https://github.com/llvm/llvm-project/pull/190999