[llvm] [GlobalIsel][AArch64] Add ADDO combine to the postlegalizer combiner (PR #101327)

[via llvm-commits]

https://github.com/KRM7 updated https://github.com/llvm/llvm-project/pull/101327

>From 82c4169d8a056ee84c03c5a1d6d831f01e017076 Mon Sep 17 00:00:00 2001
From: Krisztian Rugasi <Krisztian.Rugasi at hightec-rt.com>
Date: Fri, 2 Aug 2024 13:53:56 +0200
Subject: [PATCH] [GlobalIsel][AArch64] Add ADDO combine to the postlegalizer
 combiner

---
 llvm/lib/Target/AArch64/AArch64Combine.td     |  2 +-
 .../postlegalizer-combiner-fold-addo.mir      | 73 +++++++++++++++++++
 llvm/test/CodeGen/AArch64/popcount.ll         |  4 +-
 3 files changed, 76 insertions(+), 3 deletions(-)
 create mode 100644 llvm/test/CodeGen/AArch64/GlobalISel/postlegalizer-combiner-fold-addo.mir

diff --git a/llvm/lib/Target/AArch64/AArch64Combine.td b/llvm/lib/Target/AArch64/AArch64Combine.td
index 3f717c8a60050..90cb004dcebd3 100644
--- a/llvm/lib/Target/AArch64/AArch64Combine.td
+++ b/llvm/lib/Target/AArch64/AArch64Combine.td
@@ -322,5 +322,5 @@ def AArch64PostLegalizerCombiner
                         select_to_minmax, or_to_bsp, combine_concat_vector,
                         commute_constant_to_rhs,
                         push_freeze_to_prevent_poison_from_propagating,
-                        combine_mul_cmlt]> {
+                        combine_mul_cmlt, match_addos]> {
 }
diff --git a/llvm/test/CodeGen/AArch64/GlobalISel/postlegalizer-combiner-fold-addo.mir b/llvm/test/CodeGen/AArch64/GlobalISel/postlegalizer-combiner-fold-addo.mir
new file mode 100644
index 0000000000000..82ba11d7de0df
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/postlegalizer-combiner-fold-addo.mir
@@ -0,0 +1,73 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 2
+# RUN: llc -mtriple aarch64 -run-pass=legalizer,aarch64-postlegalizer-combiner -verify-machineinstrs %s -o - | FileCheck %s
+
+---
+name:            add_s128_unknown_bits
+body:             |
+  bb.0:
+    liveins: $q0, $q1
+    ; CHECK-LABEL: name: add_s128_unknown_bits
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: %lhs:_(s128) = COPY $q0
+    ; CHECK-NEXT: %rhs:_(s128) = COPY $q1
+    ; CHECK-NEXT: [[UV:%[0-9]+]]:_(s64), [[UV1:%[0-9]+]]:_(s64) = G_UNMERGE_VALUES %lhs(s128)
+    ; CHECK-NEXT: [[UV2:%[0-9]+]]:_(s64), [[UV3:%[0-9]+]]:_(s64) = G_UNMERGE_VALUES %rhs(s128)
+    ; CHECK-NEXT: [[UADDO:%[0-9]+]]:_(s64), [[UADDO1:%[0-9]+]]:_(s32) = G_UADDO [[UV]], [[UV2]]
+    ; CHECK-NEXT: [[UADDE:%[0-9]+]]:_(s64), [[UADDE1:%[0-9]+]]:_(s32) = G_UADDE [[UV1]], [[UV3]], [[UADDO1]]
+    ; CHECK-NEXT: %res:_(s128) = G_MERGE_VALUES [[UADDO]](s64), [[UADDE]](s64)
+    ; CHECK-NEXT: $q0 = COPY %res(s128)
+    %lhs:_(s128) = COPY $q0
+    %rhs:_(s128) = COPY $q1
+    %res:_(s128) = G_ADD %lhs, %rhs
+    $q0 = COPY %res(s128)
+...
+
+---
+name:            add_s128_low64_known_nonzero
+body:             |
+  bb.0:
+    liveins: $q0, $q1
+    ; CHECK-LABEL: name: add_s128_low64_known_nonzero
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: %a:_(s128) = COPY $q0
+    ; CHECK-NEXT: %rhs:_(s128) = COPY $q1
+    ; CHECK-NEXT: [[C:%[0-9]+]]:_(s64) = G_CONSTANT i64 -1
+    ; CHECK-NEXT: [[UV:%[0-9]+]]:_(s64), [[UV1:%[0-9]+]]:_(s64) = G_UNMERGE_VALUES %a(s128)
+    ; CHECK-NEXT: [[UV2:%[0-9]+]]:_(s64), [[UV3:%[0-9]+]]:_(s64) = G_UNMERGE_VALUES %rhs(s128)
+    ; CHECK-NEXT: [[UADDO:%[0-9]+]]:_(s64), [[UADDO1:%[0-9]+]]:_(s32) = G_UADDO [[UV2]], [[C]]
+    ; CHECK-NEXT: [[UADDE:%[0-9]+]]:_(s64), [[UADDE1:%[0-9]+]]:_(s32) = G_UADDE [[UV1]], [[UV3]], [[UADDO1]]
+    ; CHECK-NEXT: %res:_(s128) = G_MERGE_VALUES [[UADDO]](s64), [[UADDE]](s64)
+    ; CHECK-NEXT: $q0 = COPY %res(s128)
+    %a:_(s128) = COPY $q0
+    %rhs:_(s128) = COPY $q1
+    %mask:_(s128) = G_CONSTANT i128 18446744073709551615
+    %lhs:_(s128) = G_OR %a, %mask
+    %res:_(s128) = G_ADD %lhs, %rhs
+    $q0 = COPY %res(s128)
+...
+
+---
+name:            add_s128_low64_known_zero
+body:             |
+  bb.0:
+    liveins: $q0, $q1
+    ; CHECK-LABEL: name: add_s128_low64_known_zero
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: %a:_(s128) = COPY $q0
+    ; CHECK-NEXT: %rhs:_(s128) = COPY $q1
+    ; CHECK-NEXT: [[UV:%[0-9]+]]:_(s64), [[UV1:%[0-9]+]]:_(s64) = G_UNMERGE_VALUES %a(s128)
+    ; CHECK-NEXT: [[UV2:%[0-9]+]]:_(s64), [[UV3:%[0-9]+]]:_(s64) = G_UNMERGE_VALUES %rhs(s128)
+    ; CHECK-NEXT: [[C:%[0-9]+]]:_(s32) = G_CONSTANT i32 0
+    ; CHECK-NEXT: [[UADDE:%[0-9]+]]:_(s64), [[UADDE1:%[0-9]+]]:_(s32) = G_UADDE [[UV1]], [[UV3]], [[C]]
+    ; CHECK-NEXT: %res:_(s128) = G_MERGE_VALUES [[UV2]](s64), [[UADDE]](s64)
+    ; CHECK-NEXT: $q0 = COPY %res(s128)
+    %a:_(s128) = COPY $q0
+    %rhs:_(s128) = COPY $q1
+    %mask:_(s128) = G_CONSTANT i128 -18446744073709551616
+    %lhs:_(s128) = G_AND %a, %mask
+    %res:_(s128) = G_ADD %lhs, %rhs
+    $q0 = COPY %res(s128)
+...
diff --git a/llvm/test/CodeGen/AArch64/popcount.ll b/llvm/test/CodeGen/AArch64/popcount.ll
index 1fc4de1c48b7d..f9f1cd4b1fcf7 100644
--- a/llvm/test/CodeGen/AArch64/popcount.ll
+++ b/llvm/test/CodeGen/AArch64/popcount.ll
@@ -113,9 +113,9 @@ define i16 @popcount256(ptr nocapture nonnull readonly %0) {
 ;
 ; GISEL-LABEL: popcount256:
 ; GISEL:       // %bb.0: // %Entry
-; GISEL-NEXT:    ldp x8, x9, [x0, #16]
+; GISEL-NEXT:    ldp x8, x9, [x0]
 ; GISEL-NEXT:    mov v0.d[0], x8
-; GISEL-NEXT:    ldp x8, x10, [x0]
+; GISEL-NEXT:    ldp x8, x10, [x0, #16]
 ; GISEL-NEXT:    mov v1.d[0], x8
 ; GISEL-NEXT:    mov v0.d[1], x9
 ; GISEL-NEXT:    mov v1.d[1], x10