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[IndVars] Add test for missed optimizations depending on guard order.
The added tests show missed optimizations, depending on the order of loop guard conditions.
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‎llvm/test/Transforms/IndVarSimplify/loop-guard-order.ll‎

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@@ -1,6 +1,8 @@
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
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; RUN: opt -p indvars -S %s | FileCheck %s
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target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
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declare void @foo()
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define void @narrow_iv_precondition_order_1(ptr %start, i32 %base, i8 %n) {
@@ -96,3 +98,202 @@ loop:
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exit:
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ret void
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}
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define i32 @urem_order1(i32 %n) {
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; CHECK-LABEL: define i32 @urem_order1(
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; CHECK-SAME: i32 [[N:%.*]]) {
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; CHECK-NEXT: [[ENTRY:.*]]:
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; CHECK-NEXT: [[UREM:%.*]] = urem i32 [[N]], 3
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; CHECK-NEXT: [[UREM_ZERO:%.*]] = icmp eq i32 [[UREM]], 0
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; CHECK-NEXT: br i1 [[UREM_ZERO]], label %[[PH:.*]], label %[[EXIT:.*]]
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; CHECK: [[PH]]:
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; CHECK-NEXT: [[N_NON_ZERO:%.*]] = icmp ne i32 [[N]], 0
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; CHECK-NEXT: br i1 [[N_NON_ZERO]], label %[[LOOP_PREHEADER:.*]], label %[[EXIT]]
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; CHECK: [[LOOP_PREHEADER]]:
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; CHECK-NEXT: br label %[[LOOP:.*]]
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; CHECK: [[LOOP]]:
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; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_NEXT:%.*]], %[[LOOP]] ], [ 0, %[[LOOP_PREHEADER]] ]
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; CHECK-NEXT: call void @foo()
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; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 3
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; CHECK-NEXT: [[EC:%.*]] = icmp eq i32 [[IV_NEXT]], [[N]]
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; CHECK-NEXT: br i1 [[EC]], label %[[EXIT_LOOPEXIT:.*]], label %[[LOOP]]
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; CHECK: [[EXIT_LOOPEXIT]]:
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; CHECK-NEXT: br label %[[EXIT]]
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; CHECK: [[EXIT]]:
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; CHECK-NEXT: [[RES:%.*]] = phi i32 [ 1, %[[ENTRY]] ], [ 2, %[[PH]] ], [ 3, %[[EXIT_LOOPEXIT]] ]
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; CHECK-NEXT: ret i32 [[RES]]
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;
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entry:
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%urem = urem i32 %n, 3
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%urem.zero = icmp eq i32 %urem, 0
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br i1 %urem.zero, label %ph, label %exit
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ph:
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%n.non.zero = icmp ne i32 %n, 0
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br i1 %n.non.zero, label %loop, label %exit
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loop:
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%iv = phi i32 [ 0, %ph ], [ %iv.next, %loop ]
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call void @foo()
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%iv.next = add i32 %iv, 3
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%ec = icmp eq i32 %iv.next, %n
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br i1 %ec, label %exit, label %loop
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exit:
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%res = phi i32 [ 1, %entry ], [ 2, %ph ], [ 3, %loop ]
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ret i32 %res
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}
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define i32 @urem_order2(i32 %n) {
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; CHECK-LABEL: define i32 @urem_order2(
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; CHECK-SAME: i32 [[N:%.*]]) {
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; CHECK-NEXT: [[ENTRY:.*]]:
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; CHECK-NEXT: [[N_NON_ZERO:%.*]] = icmp ne i32 [[N]], 0
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; CHECK-NEXT: br i1 [[N_NON_ZERO]], label %[[PH:.*]], label %[[EXIT:.*]]
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; CHECK: [[PH]]:
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; CHECK-NEXT: [[UREM:%.*]] = urem i32 [[N]], 3
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; CHECK-NEXT: [[UREM_ZERO:%.*]] = icmp eq i32 [[UREM]], 0
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; CHECK-NEXT: br i1 [[UREM_ZERO]], label %[[LOOP_PREHEADER:.*]], label %[[EXIT]]
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; CHECK: [[LOOP_PREHEADER]]:
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; CHECK-NEXT: br label %[[LOOP:.*]]
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; CHECK: [[LOOP]]:
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; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_NEXT:%.*]], %[[LOOP]] ], [ 0, %[[LOOP_PREHEADER]] ]
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; CHECK-NEXT: call void @foo()
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; CHECK-NEXT: [[IV_NEXT]] = add nuw i32 [[IV]], 3
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; CHECK-NEXT: [[EC:%.*]] = icmp eq i32 [[IV_NEXT]], [[N]]
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; CHECK-NEXT: br i1 [[EC]], label %[[EXIT_LOOPEXIT:.*]], label %[[LOOP]]
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; CHECK: [[EXIT_LOOPEXIT]]:
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; CHECK-NEXT: br label %[[EXIT]]
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; CHECK: [[EXIT]]:
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; CHECK-NEXT: [[RES:%.*]] = phi i32 [ 1, %[[ENTRY]] ], [ 2, %[[PH]] ], [ 3, %[[EXIT_LOOPEXIT]] ]
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; CHECK-NEXT: ret i32 [[RES]]
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;
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entry:
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%n.non.zero = icmp ne i32 %n, 0
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br i1 %n.non.zero, label %ph, label %exit
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ph:
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%urem = urem i32 %n, 3
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%urem.zero = icmp eq i32 %urem, 0
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br i1 %urem.zero, label %loop, label %exit
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loop:
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%iv = phi i32 [ 0, %ph ], [ %iv.next, %loop ]
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call void @foo()
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%iv.next = add i32 %iv, 3
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%ec = icmp eq i32 %iv.next, %n
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br i1 %ec, label %exit, label %loop
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exit:
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%res = phi i32 [ 1, %entry ], [ 2, %ph ], [ 3, %loop ]
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ret i32 %res
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}
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define i64 @test_loop_with_div_order_1(i64 %n) {
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; CHECK-LABEL: define i64 @test_loop_with_div_order_1(
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; CHECK-SAME: i64 [[N:%.*]]) {
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; CHECK-NEXT: [[ENTRY:.*:]]
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; CHECK-NEXT: [[IS_ZERO:%.*]] = icmp eq i64 [[N]], 0
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; CHECK-NEXT: br i1 [[IS_ZERO]], label %[[EXIT:.*]], label %[[CHECK_BOUNDS:.*]]
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; CHECK: [[CHECK_BOUNDS]]:
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; CHECK-NEXT: [[N_PLUS_63:%.*]] = add i64 [[N]], 63
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; CHECK-NEXT: [[UPPER_BOUND:%.*]] = lshr i64 [[N_PLUS_63]], 6
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; CHECK-NEXT: [[BOUNDS_CHECK:%.*]] = icmp ult i64 [[N_PLUS_63]], 64
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; CHECK-NEXT: br i1 [[BOUNDS_CHECK]], label %[[EXIT]], label %[[CHECK_PARITY:.*]]
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; CHECK: [[CHECK_PARITY]]:
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; CHECK-NEXT: [[IS_ODD:%.*]] = and i64 [[N]], 1
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; CHECK-NEXT: [[PARITY_CHECK:%.*]] = icmp eq i64 [[IS_ODD]], 0
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; CHECK-NEXT: br i1 [[PARITY_CHECK]], label %[[LOOP_PREHEADER:.*]], label %[[EXIT]]
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; CHECK: [[LOOP_PREHEADER]]:
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; CHECK-NEXT: [[UMAX:%.*]] = call i64 @llvm.umax.i64(i64 [[UPPER_BOUND]], i64 1)
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; CHECK-NEXT: br label %[[LOOP:.*]]
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; CHECK: [[LOOP]]:
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; CHECK-NEXT: [[IV:%.*]] = phi i64 [ [[IV_NEXT:%.*]], %[[LOOP]] ], [ 0, %[[LOOP_PREHEADER]] ]
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; CHECK-NEXT: [[DUMMY:%.*]] = load volatile i64, ptr null, align 8
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; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
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; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[IV_NEXT]], [[UMAX]]
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; CHECK-NEXT: br i1 [[EXITCOND]], label %[[LOOP]], label %[[EXIT_LOOPEXIT:.*]]
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; CHECK: [[EXIT_LOOPEXIT]]:
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; CHECK-NEXT: br label %[[EXIT]]
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; CHECK: [[EXIT]]:
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; CHECK-NEXT: ret i64 0
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;
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entry:
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%is_zero = icmp eq i64 %n, 0
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br i1 %is_zero, label %exit, label %check_bounds
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check_bounds:
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%n_plus_63 = add i64 %n, 63
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%upper_bound = lshr i64 %n_plus_63, 6
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%bounds_check = icmp ult i64 %n_plus_63, 64
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br i1 %bounds_check, label %exit, label %check_parity
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check_parity:
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%is_odd = and i64 %n, 1
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%parity_check = icmp eq i64 %is_odd, 0
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br i1 %parity_check, label %loop, label %exit
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loop:
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%iv = phi i64 [ %iv_next, %loop ], [ 0, %check_parity ]
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%dummy = load volatile i64, ptr null, align 8
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%iv_next = add i64 %iv, 1
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%exit_cond = icmp ult i64 %iv_next, %upper_bound
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br i1 %exit_cond, label %loop, label %exit
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exit:
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ret i64 0
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}
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define i64 @test_loop_with_div_order_2(i64 %n) {
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; CHECK-LABEL: define i64 @test_loop_with_div_order_2(
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; CHECK-SAME: i64 [[N:%.*]]) {
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; CHECK-NEXT: [[ENTRY:.*:]]
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; CHECK-NEXT: [[N_PLUS_63:%.*]] = add i64 [[N]], 63
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; CHECK-NEXT: [[UPPER_BOUND:%.*]] = lshr i64 [[N_PLUS_63]], 6
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; CHECK-NEXT: [[BOUNDS_CHECK:%.*]] = icmp ult i64 [[N_PLUS_63]], 64
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; CHECK-NEXT: br i1 [[BOUNDS_CHECK]], label %[[EXIT:.*]], label %[[CHECK_BOUNDS:.*]]
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; CHECK: [[CHECK_BOUNDS]]:
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; CHECK-NEXT: [[IS_ZERO:%.*]] = icmp eq i64 [[N]], 0
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; CHECK-NEXT: br i1 [[IS_ZERO]], label %[[EXIT]], label %[[CHECK_PARITY:.*]]
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; CHECK: [[CHECK_PARITY]]:
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; CHECK-NEXT: [[IS_ODD:%.*]] = and i64 [[N]], 1
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; CHECK-NEXT: [[PARITY_CHECK:%.*]] = icmp eq i64 [[IS_ODD]], 0
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; CHECK-NEXT: br i1 [[PARITY_CHECK]], label %[[LOOP_PREHEADER:.*]], label %[[EXIT]]
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; CHECK: [[LOOP_PREHEADER]]:
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; CHECK-NEXT: br label %[[LOOP:.*]]
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; CHECK: [[LOOP]]:
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; CHECK-NEXT: [[IV:%.*]] = phi i64 [ [[IV_NEXT:%.*]], %[[LOOP]] ], [ 0, %[[LOOP_PREHEADER]] ]
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; CHECK-NEXT: [[DUMMY:%.*]] = load volatile i64, ptr null, align 8
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; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
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; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[IV_NEXT]], [[UPPER_BOUND]]
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; CHECK-NEXT: br i1 [[EXITCOND]], label %[[LOOP]], label %[[EXIT_LOOPEXIT:.*]]
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; CHECK: [[EXIT_LOOPEXIT]]:
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; CHECK-NEXT: br label %[[EXIT]]
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; CHECK: [[EXIT]]:
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; CHECK-NEXT: ret i64 0
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;
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entry:
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%n_plus_63 = add i64 %n, 63
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%upper_bound = lshr i64 %n_plus_63, 6
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%bounds_check = icmp ult i64 %n_plus_63, 64
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br i1 %bounds_check, label %exit, label %check_bounds
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check_bounds:
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%is_zero = icmp eq i64 %n, 0
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br i1 %is_zero, label %exit, label %check_parity
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check_parity:
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%is_odd = and i64 %n, 1
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%parity_check = icmp eq i64 %is_odd, 0
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br i1 %parity_check, label %loop, label %exit
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loop:
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%iv = phi i64 [ %iv_next, %loop ], [ 0, %check_parity ]
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%dummy = load volatile i64, ptr null, align 8
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%iv_next = add i64 %iv, 1
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%exit_cond = icmp ult i64 %iv_next, %upper_bound
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br i1 %exit_cond, label %loop, label %exit
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exit:
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ret i64 0
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}

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