[llvm] [AArch64] Generate zeroing forms of certain SVE2.2 instructions (3/11) (PR #116829)

[via llvm-commits]

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@@ -0,0 +1,147 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mattr=+sve2   < %s | FileCheck %s
+; RUN: llc -mattr=+sve2p2 < %s | FileCheck %s -check-prefix CHECK-2p2
+
+; RUN: llc -mattr=+sme2   -force-streaming < %s | FileCheck %s
+; RUN: llc -mattr=+sme2p2 -force-streaming < %s | FileCheck %s -check-prefix CHECK-2p2
+
+target triple = "aarch64-linux"
+
+define <vscale x 4 x float> @test_svcvtlt_f32_f16_x_1(<vscale x 4 x i1> %pg, <vscale x 8 x half> %x) {
+; CHECK-LABEL: test_svcvtlt_f32_f16_x_1:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    fcvtlt z0.s, p0/m, z0.h
+; CHECK-NEXT:    ret
+;
+; CHECK-2p2-LABEL: test_svcvtlt_f32_f16_x_1:
+; CHECK-2p2:       // %bb.0: // %entry
+; CHECK-2p2-NEXT:    fcvtlt z0.s, p0/z, z0.h
+; CHECK-2p2-NEXT:    ret
+entry:
+  %0 = tail call <vscale x 4 x float> @llvm.aarch64.sve.fcvtlt.f32f16(<vscale x 4 x float> undef, <vscale x 4 x i1> %pg, <vscale x 8 x half> %x)
+  ret <vscale x 4 x float> %0
+}
+
+define <vscale x 4 x float> @test_svcvtlt_f32_f16_x_2(<vscale x 4 x i1> %pg, double %z0, <vscale x 8 x half> %x) {
+; CHECK-LABEL: test_svcvtlt_f32_f16_x_2:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    fcvtlt z0.s, p0/m, z1.h
+; CHECK-NEXT:    ret
+;
+; CHECK-2p2-LABEL: test_svcvtlt_f32_f16_x_2:
+; CHECK-2p2:       // %bb.0: // %entry
+; CHECK-2p2-NEXT:    fcvtlt z0.s, p0/z, z1.h
+; CHECK-2p2-NEXT:    ret
+entry:
+  %0 = tail call <vscale x 4 x float> @llvm.aarch64.sve.fcvtlt.f32f16(<vscale x 4 x float> undef, <vscale x 4 x i1> %pg, <vscale x 8 x half> %x)
+  ret <vscale x 4 x float> %0
+}
+
+define <vscale x 4 x float> @test_svcvtlt_f32_f16_z(<vscale x 4 x i1> %pg, double %z0, <vscale x 8 x half> %x) {
+; CHECK-LABEL: test_svcvtlt_f32_f16_z:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    mov z0.s, #0 // =0x0
+; CHECK-NEXT:    fcvtlt z0.s, p0/m, z1.h
+; CHECK-NEXT:    ret
+;
+; CHECK-2p2-LABEL: test_svcvtlt_f32_f16_z:
+; CHECK-2p2:       // %bb.0: // %entry
+; CHECK-2p2-NEXT:    fcvtlt z0.s, p0/z, z1.h
+; CHECK-2p2-NEXT:    ret
+entry:
+  %0 = tail call <vscale x 4 x float> @llvm.aarch64.sve.fcvtlt.f32f16(<vscale x 4 x float> zeroinitializer, <vscale x 4 x i1> %pg, <vscale x 8 x half> %x)
+  ret <vscale x 4 x float> %0
+}
+
+define <vscale x 2 x double> @test_svcvtlt_f64_f32_x_1(<vscale x 2 x i1> %pg, <vscale x 4 x float> %x) {
+; CHECK-LABEL: test_svcvtlt_f64_f32_x_1:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    fcvtlt z0.d, p0/m, z0.s
+; CHECK-NEXT:    ret
+;
+; CHECK-2p2-LABEL: test_svcvtlt_f64_f32_x_1:
+; CHECK-2p2:       // %bb.0: // %entry
+; CHECK-2p2-NEXT:    fcvtlt z0.d, p0/z, z0.s
+; CHECK-2p2-NEXT:    ret
+entry:
+  %0 = tail call <vscale x 2 x double> @llvm.aarch64.sve.fcvtlt.f64f32(<vscale x 2 x double> undef, <vscale x 2 x i1> %pg, <vscale x 4 x float> %x)
+  ret <vscale x 2 x double> %0
+}
+
+define <vscale x 2 x double> @test_svcvtlt_f64_f32_x_2(<vscale x 2 x i1> %pg, double %z0, <vscale x 4 x float> %x) {
+; CHECK-LABEL: test_svcvtlt_f64_f32_x_2:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    fcvtlt z0.d, p0/m, z1.s
+; CHECK-NEXT:    ret
+;
+; CHECK-2p2-LABEL: test_svcvtlt_f64_f32_x_2:
+; CHECK-2p2:       // %bb.0: // %entry
+; CHECK-2p2-NEXT:    fcvtlt z0.d, p0/z, z1.s
+; CHECK-2p2-NEXT:    ret
+entry:
+  %0 = tail call <vscale x 2 x double> @llvm.aarch64.sve.fcvtlt.f64f32(<vscale x 2 x double> undef, <vscale x 2 x i1> %pg, <vscale x 4 x float> %x)
+  ret <vscale x 2 x double> %0
+}
+
+define <vscale x 2 x double> @test_svcvtlt_f64_f32_z(<vscale x 2 x i1> %pg, double %z0, <vscale x 4 x float> %x) {
+; CHECK-LABEL: test_svcvtlt_f64_f32_z:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    mov z0.d, #0 // =0x0
+; CHECK-NEXT:    fcvtlt z0.d, p0/m, z1.s
+; CHECK-NEXT:    ret
+;
+; CHECK-2p2-LABEL: test_svcvtlt_f64_f32_z:
+; CHECK-2p2:       // %bb.0: // %entry
+; CHECK-2p2-NEXT:    fcvtlt z0.d, p0/z, z1.s
+; CHECK-2p2-NEXT:    ret
+entry:
+  %0 = tail call <vscale x 2 x double> @llvm.aarch64.sve.fcvtlt.f64f32(<vscale x 2 x double> zeroinitializer, <vscale x 2 x i1> %pg, <vscale x 4 x float> %x)
+  ret <vscale x 2 x double> %0
+}
+
+define <vscale x 4 x float> @test_svcvtx_f32_f64_x_1(<vscale x 2 x i1> %pg, <vscale x 2 x double> %x) {
+; CHECK-LABEL: test_svcvtx_f32_f64_x_1:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    fcvtx z0.s, p0/m, z0.d
+; CHECK-NEXT:    ret
+;
+; CHECK-2p2-LABEL: test_svcvtx_f32_f64_x_1:
+; CHECK-2p2:       // %bb.0: // %entry
+; CHECK-2p2-NEXT:    fcvtx z0.s, p0/z, z0.d
+; CHECK-2p2-NEXT:    ret
+entry:
+  %0 = tail call <vscale x 4 x float> @llvm.aarch64.sve.fcvtx.f32f64(<vscale x 4 x float> undef, <vscale x 2 x i1> %pg, <vscale x 2 x double> %x)
+  ret <vscale x 4 x float> %0
+}
+
+define <vscale x 4 x float> @test_svcvtx_f32_f64_x_2(<vscale x 2 x i1> %pg, <vscale x 2 x double> %x) {
----------------
CarolineConcatto wrote:

About the test not having movprfx :
I believe the reason is because it is using the function instCombineSVEAllOrNoActiveUnary to replace the first operand by undef, but it still uses the  merge instruction, so the test is still valid as now it changes to the zero instruction.
However  this change, IMO,  should not have any performance issues.

https://github.com/llvm/llvm-project/pull/116829