From 291450d8934adc80f8551ef2cda4db80d49875d3 Mon Sep 17 00:00:00 2001
From: Nikita Popov <npopov@redhat.com>
Date: Fri, 25 Feb 2022 13:18:45 +0100
Subject: [PATCH] [MergeICmps] Add opaque pointer test (NFC)

We fail to merge the icmps here, because the zero-offset access
does not go through a GEP.
---
 llvm/test/Transforms/MergeICmps/X86/opaque-ptr.ll | 43 +++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 llvm/test/Transforms/MergeICmps/X86/opaque-ptr.ll

diff --git a/llvm/test/Transforms/MergeICmps/X86/opaque-ptr.ll b/llvm/test/Transforms/MergeICmps/X86/opaque-ptr.ll
new file mode 100644
index 0000000..bb364df
--- /dev/null
+++ b/llvm/test/Transforms/MergeICmps/X86/opaque-ptr.ll
@@ -0,0 +1,43 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -mergeicmps -opaque-pointers < %s | FileCheck %s
+
+target triple = "x86_64-unknown-unknown"
+
+%S = type { i32, i32 }
+
+define i1 @test(ptr dereferenceable(8) %a, ptr dereferenceable(8) %b) {
+; CHECK-LABEL: @test(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[V0:%.*]] = load i32, ptr [[A:%.*]], align 4
+; CHECK-NEXT:    [[V1:%.*]] = load i32, ptr [[B:%.*]], align 4
+; CHECK-NEXT:    [[CMP_I:%.*]] = icmp eq i32 [[V0]], [[V1]]
+; CHECK-NEXT:    br i1 [[CMP_I]], label [[LAND_RHS_I:%.*]], label [[OPEQ1_EXIT:%.*]]
+; CHECK:       land.rhs.i:
+; CHECK-NEXT:    [[SECOND_I:%.*]] = getelementptr inbounds [[S:%.*]], ptr [[A]], i64 0, i32 1
+; CHECK-NEXT:    [[V2:%.*]] = load i32, ptr [[SECOND_I]], align 4
+; CHECK-NEXT:    [[SECOND2_I:%.*]] = getelementptr inbounds [[S]], ptr [[B]], i64 0, i32 1
+; CHECK-NEXT:    [[V3:%.*]] = load i32, ptr [[SECOND2_I]], align 4
+; CHECK-NEXT:    [[CMP3_I:%.*]] = icmp eq i32 [[V2]], [[V3]]
+; CHECK-NEXT:    br label [[OPEQ1_EXIT]]
+; CHECK:       opeq1.exit:
+; CHECK-NEXT:    [[PHI:%.*]] = phi i1 [ false, [[ENTRY:%.*]] ], [ [[CMP3_I]], [[LAND_RHS_I]] ]
+; CHECK-NEXT:    ret i1 [[PHI]]
+;
+entry:
+  %v0 = load i32, ptr %a, align 4
+  %v1 = load i32, ptr %b, align 4
+  %cmp.i = icmp eq i32 %v0, %v1
+  br i1 %cmp.i, label %land.rhs.i, label %opeq1.exit
+
+land.rhs.i:                                       ; preds = %entry
+  %second.i = getelementptr inbounds %S, ptr %a, i64 0, i32 1
+  %v2 = load i32, ptr %second.i, align 4
+  %second2.i = getelementptr inbounds %S, ptr %b, i64 0, i32 1
+  %v3 = load i32, ptr %second2.i, align 4
+  %cmp3.i = icmp eq i32 %v2, %v3
+  br label %opeq1.exit
+
+opeq1.exit:                                       ; preds = %land.rhs.i, %entry
+  %phi = phi i1 [ false, %entry ], [ %cmp3.i, %land.rhs.i ]
+  ret i1 %phi
+}
-- 
2.7.4