[llvm] [AArch64][SME] Make getRegAllocationHints stricter for multi-vector loads (PR #123081)

[Sander de Smalen via llvm-commits]

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@@ -0,0 +1,183 @@
+# RUN: llc -force-streaming -verify-machineinstrs -enable-subreg-liveness -start-before=greedy %s -o - | FileCheck %s
+
+# No available group of four strided x4 registers, fall back on default allocation order
+--- |
+  ; ModuleID = '<stdin>'
+  source_filename = "<stdin>"
+  target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128-Fn32"
+  target triple = "aarch64-linux-gnu"
+
+  ; Function Attrs: nounwind
+  define void @form_4x_tuple_many_live(ptr %ptr, i64 %stride, <vscale x 16 x i8> %scalable_arg) #0 {
+  entry:
+    %0 = tail call target("aarch64.svcount") @llvm.aarch64.sve.ptrue.c8()
+    %1 = tail call { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } @llvm.aarch64.sve.ld1.pn.x4.nxv16i8(target("aarch64.svcount") %0, ptr %ptr)
+    %2 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %1, 0
+    %3 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %1, 1
+    %4 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %1, 2
+    %5 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %1, 3
+    %arrayidx2 = getelementptr inbounds i8, ptr %ptr, i64 %stride
+    %6 = tail call { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } @llvm.aarch64.sve.ld1.pn.x4.nxv16i8(target("aarch64.svcount") %0, ptr %arrayidx2)
+    %7 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %6, 0
+    %8 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %6, 1
+    %9 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %6, 2
+    %10 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %6, 3
+    %mul3 = shl i64 %stride, 1
+    %arrayidx4 = getelementptr inbounds i8, ptr %ptr, i64 %mul3
+    %11 = tail call { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } @llvm.aarch64.sve.ld1.pn.x4.nxv16i8(target("aarch64.svcount") %0, ptr %arrayidx4)
+    %12 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %11, 0
+    %13 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %11, 1
+    %14 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %11, 2
+    %15 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %11, 3
+    %mul5 = mul i64 %stride, 3
+    %arrayidx6 = getelementptr inbounds i8, ptr %ptr, i64 %mul5
+    %16 = tail call { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } @llvm.aarch64.sve.ld1.pn.x4.nxv16i8(target("aarch64.svcount") %0, ptr %arrayidx6)
+    %17 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %16, 0
+    %18 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %16, 1
+    %19 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %16, 2
+    %20 = extractvalue { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } %16, 3
+    tail call void @llvm.aarch64.sme.udot.lane.za32.vg1x4.nxv16i8(i32 0, <vscale x 16 x i8> %2, <vscale x 16 x i8> %7, <vscale x 16 x i8> %12, <vscale x 16 x i8> %17, <vscale x 16 x i8> poison, i32 0)
+    tail call void @llvm.aarch64.sme.udot.lane.za32.vg1x4.nxv16i8(i32 0, <vscale x 16 x i8> %3, <vscale x 16 x i8> %8, <vscale x 16 x i8> %13, <vscale x 16 x i8> %18, <vscale x 16 x i8> poison, i32 0)
+    tail call void @llvm.aarch64.sme.udot.lane.za32.vg1x4.nxv16i8(i32 0, <vscale x 16 x i8> %4, <vscale x 16 x i8> %9, <vscale x 16 x i8> %14, <vscale x 16 x i8> %19, <vscale x 16 x i8> poison, i32 0)
+    tail call void @llvm.aarch64.sme.udot.lane.za32.vg1x4.nxv16i8(i32 0, <vscale x 16 x i8> %5, <vscale x 16 x i8> %10, <vscale x 16 x i8> %15, <vscale x 16 x i8> %20, <vscale x 16 x i8> poison, i32 0)
+    store <vscale x 16 x i8> %scalable_arg, ptr %ptr, align 16
+    ret void
+  }
+
+  ; Function Attrs: nocallback nofree nosync nounwind willreturn
+  declare void @llvm.aarch64.sme.udot.lane.za32.vg1x4.nxv16i8(i32, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, i32 immarg) #1
+
+  ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: read)
+  declare { <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8>, <vscale x 16 x i8> } @llvm.aarch64.sve.ld1.pn.x4.nxv16i8(target("aarch64.svcount"), ptr) #2
+
+  ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(none)
+  declare target("aarch64.svcount") @llvm.aarch64.sve.ptrue.c8() #3
+
+  attributes #0 = { nounwind "target-features"="+sme2" }
+  attributes #1 = { nocallback nofree nosync nounwind willreturn }
+  attributes #2 = { nocallback nofree nosync nounwind willreturn memory(argmem: read) }
+  attributes #3 = { nocallback nofree nosync nounwind willreturn memory(none) }
+
+...
+---
+name:            form_4x_tuple_many_live
----------------
sdesmalen-arm wrote:

Probably a lot of these fields are not necessary for this test (the LLVM IR above is probably also not required), could you clean this test up a bit?

https://github.com/llvm/llvm-project/pull/123081