[RISCV][test] Precommit LSR test that partially motivates #89927

Author: asb

llvm/test/Transforms/LoopStrengthReduce/RISCV/many-geps.ll

@@ -0,0 +1,109 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt < %s -loop-reduce -S | FileCheck %s
+
+target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n64-S128"
+target triple = "riscv64"
+
+; This test was added as example motivation for the changes in #89927, which
+; causes LSR to drop solutions if deemed to be less profitable than the
+; starting point. At the time of adding this test, LSR's search heuristics
+; best identified solution was an unprofitable one. This could of course
+; change with future LSR improvements.
+
+%struct = type { i64, i32, i32, i32, i32, i32, i32, i32, i32, i64, i32, i64, i64, i32, i64 }
+
+define i32 @main() {
+; CHECK-LABEL: define i32 @main() {
+; CHECK-NEXT:    [[CALL:%.*]] = tail call ptr null(i64 0)
+; CHECK-NEXT:    br label %[[BB2:.*]]
+; CHECK:       [[BB1:.*:]]
+; CHECK-NEXT:    [[LOAD:%.*]] = load i32, ptr [[CALL]], align 4
+; CHECK-NEXT:    ret i32 0
+; CHECK:       [[BB2]]:
+; CHECK-NEXT:    [[LSR_IV30:%.*]] = phi i64 [ [[LSR_IV_NEXT31:%.*]], %[[BB2]] ], [ 8, [[BB:%.*]] ]
+; CHECK-NEXT:    [[LSR_IV27:%.*]] = phi i64 [ [[LSR_IV_NEXT28:%.*]], %[[BB2]] ], [ 12, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV24:%.*]] = phi i64 [ [[LSR_IV_NEXT25:%.*]], %[[BB2]] ], [ 16, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV21:%.*]] = phi i64 [ [[LSR_IV_NEXT22:%.*]], %[[BB2]] ], [ 20, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV18:%.*]] = phi i64 [ [[LSR_IV_NEXT19:%.*]], %[[BB2]] ], [ 24, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV15:%.*]] = phi i64 [ [[LSR_IV_NEXT16:%.*]], %[[BB2]] ], [ 28, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV12:%.*]] = phi i64 [ [[LSR_IV_NEXT13:%.*]], %[[BB2]] ], [ 32, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV9:%.*]] = phi i64 [ [[LSR_IV_NEXT10:%.*]], %[[BB2]] ], [ 36, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV4:%.*]] = phi i64 [ [[LSR_IV_NEXT5:%.*]], %[[BB2]] ], [ 40, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV1:%.*]] = phi i64 [ [[LSR_IV_NEXT2:%.*]], %[[BB2]] ], [ 48, [[BB]] ]
+; CHECK-NEXT:    [[LSR_IV:%.*]] = phi i64 [ [[LSR_IV_NEXT:%.*]], %[[BB2]] ], [ 72, [[BB]] ]
+; CHECK-NEXT:    [[SCEVGEP32:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV30]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP32]], align 8
+; CHECK-NEXT:    [[SCEVGEP29:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV27]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP29]], align 4
+; CHECK-NEXT:    [[SCEVGEP26:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV24]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP26]], align 8
+; CHECK-NEXT:    [[SCEVGEP23:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV21]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP23]], align 4
+; CHECK-NEXT:    [[SCEVGEP20:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV18]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP20]], align 8
+; CHECK-NEXT:    [[SCEVGEP17:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV15]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP17]], align 4
+; CHECK-NEXT:    [[SCEVGEP14:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV12]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP14]], align 8
+; CHECK-NEXT:    [[SCEVGEP11:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV9]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP11]], align 4
+; CHECK-NEXT:    [[SCEVGEP6:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV4]]
+; CHECK-NEXT:    store i64 0, ptr [[SCEVGEP6]], align 8
+; CHECK-NEXT:    [[SCEVGEP3:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV1]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP3]], align 8
+; CHECK-NEXT:    [[SCEVGEP:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV]]
+; CHECK-NEXT:    store i32 0, ptr [[SCEVGEP]], align 8
+; CHECK-NEXT:    [[SCEVGEP7:%.*]] = getelementptr i8, ptr [[CALL]], i64 [[LSR_IV4]]
+; CHECK-NEXT:    [[SCEVGEP8:%.*]] = getelementptr i8, ptr [[SCEVGEP7]], i64 40
+; CHECK-NEXT:    store i64 0, ptr [[SCEVGEP8]], align 8
+; CHECK-NEXT:    [[LSR_IV_NEXT]] = add i64 [[LSR_IV]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT2]] = add i64 [[LSR_IV1]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT5]] = add i64 [[LSR_IV4]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT10]] = add i64 [[LSR_IV9]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT13]] = add i64 [[LSR_IV12]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT16]] = add i64 [[LSR_IV15]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT19]] = add i64 [[LSR_IV18]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT22]] = add i64 [[LSR_IV21]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT25]] = add i64 [[LSR_IV24]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT28]] = add i64 [[LSR_IV27]], 88
+; CHECK-NEXT:    [[LSR_IV_NEXT31]] = add i64 [[LSR_IV30]], 88
+; CHECK-NEXT:    br label %[[BB2]]
+;
+0:
+  %call = tail call ptr null(i64 0)
+  br label %2
+
+1:
+  %load = load i32, ptr %call, align 4
+  ret i32 0
+
+2:
+  %phi = phi i64 [ 0, %0 ], [ %add, %2 ]
+  %getelementptr = getelementptr %struct, ptr %call, i64 %phi
+  %getelementptr3 = getelementptr i8, ptr %getelementptr, i64 8
+  store i32 0, ptr %getelementptr3, align 8
+  %getelementptr4 = getelementptr i8, ptr %getelementptr, i64 12
+  store i32 0, ptr %getelementptr4, align 4
+  %getelementptr5 = getelementptr i8, ptr %getelementptr, i64 16
+  store i32 0, ptr %getelementptr5, align 8
+  %getelementptr6 = getelementptr i8, ptr %getelementptr, i64 20
+  store i32 0, ptr %getelementptr6, align 4
+  %getelementptr7 = getelementptr i8, ptr %getelementptr, i64 24
+  store i32 0, ptr %getelementptr7, align 8
+  %getelementptr8 = getelementptr i8, ptr %getelementptr, i64 28
+  store i32 0, ptr %getelementptr8, align 4
+  %getelementptr9 = getelementptr i8, ptr %getelementptr, i64 32
+  store i32 0, ptr %getelementptr9, align 8
+  %getelementptr10 = getelementptr i8, ptr %getelementptr, i64 36
+  store i32 0, ptr %getelementptr10, align 4
+  %getelementptr11 = getelementptr i8, ptr %getelementptr, i64 40
+  store i64 0, ptr %getelementptr11, align 8
+  %getelementptr12 = getelementptr i8, ptr %getelementptr, i64 48
+  store i32 0, ptr %getelementptr12, align 8
+  %getelementptr13 = getelementptr i8, ptr %getelementptr, i64 72
+  store i32 0, ptr %getelementptr13, align 8
+  %getelementptr14 = getelementptr i8, ptr %getelementptr, i64 80
+  store i64 0, ptr %getelementptr14, align 8
+  %add = add i64 %phi, 1
+  br label %2
+}