[llvm] [AArch64][SVE] Combine UXT[BHW] intrinsics to AND. (PR #137956)

[Paul Walker via llvm-commits]

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@@ -0,0 +1,99 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -passes=instcombine < %s | FileCheck %s
+
+target triple = "aarch64-unknown-linux-gnu"
+
+; Test that we combine uxtb to and_u for all-active predicates.
+
+define <vscale x 2 x i64> @uxtb_m_64(<vscale x 2 x i64> %0, <vscale x 2 x i64> %1) #0 {
+; CHECK-LABEL: define <vscale x 2 x i64> @uxtb_m_64(
+; CHECK-SAME: <vscale x 2 x i64> [[TMP0:%.*]], <vscale x 2 x i64> [[TMP1:%.*]]) #[[ATTR0]] {
+; CHECK-NEXT:    [[TMP3:%.*]] = call <vscale x 2 x i64> @llvm.aarch64.sve.and.u.nxv2i64(<vscale x 2 x i1> splat (i1 true), <vscale x 2 x i64> [[TMP0]], <vscale x 2 x i64> splat (i64 255))
+; CHECK-NEXT:    ret <vscale x 2 x i64> [[TMP3]]
+;
+  %3 = tail call <vscale x 2 x i64> @llvm.aarch64.sve.uxtb.nxv2i64(<vscale x 2 x i64> %1, <vscale x 2 x i1> splat (i1 true), <vscale x 2 x i64> %0)
+  ret <vscale x 2 x i64> %3
+}
+
+; Test that we combine uxtb to and_u for undef (``unknown'') passthrough.
+
+define <vscale x 2 x i64> @uxtb_x_64(<vscale x 16 x i1> %0, <vscale x 2 x i64> %1) #0 {
+; CHECK-LABEL: define <vscale x 2 x i64> @uxtb_x_64(
+; CHECK-SAME: <vscale x 16 x i1> [[TMP0:%.*]], <vscale x 2 x i64> [[TMP1:%.*]]) #[[ATTR0]] {
+; CHECK-NEXT:    [[TMP3:%.*]] = tail call <vscale x 2 x i1> @llvm.aarch64.sve.convert.from.svbool.nxv2i1(<vscale x 16 x i1> [[TMP0]])
+; CHECK-NEXT:    [[TMP4:%.*]] = call <vscale x 2 x i64> @llvm.aarch64.sve.and.u.nxv2i64(<vscale x 2 x i1> [[TMP3]], <vscale x 2 x i64> [[TMP1]], <vscale x 2 x i64> splat (i64 255))
+; CHECK-NEXT:    ret <vscale x 2 x i64> [[TMP4]]
+;
+  %3 = tail call <vscale x 2 x i1> @llvm.aarch64.sve.convert.from.svbool.nxv2i1(<vscale x 16 x i1> %0)
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paulwalker-arm wrote:

You can pass `<vscale x 2 x i1>` directly as a parameter and then you'll not need the `convert` call.

https://github.com/llvm/llvm-project/pull/137956