xref: /llvm-project/llvm/test/Transforms/IRCE/range_intersect_miscompile.ll (revision 483e92468e597b73c646182bd755a0d5ef67d327)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
2; RUN: opt -verify-loop-info -irce-print-changed-loops -passes=irce -S < %s 2>&1 | FileCheck %s
3; RUN: opt -verify-loop-info -irce-print-changed-loops -passes='require<branch-prob>,irce' -S < %s 2>&1 | FileCheck %s
4
5; CHECK-LABEL: irce: in function test_01: constrained Loop at depth 1 containing:
6; CHECK-LABEL: irce: in function test_02: constrained Loop at depth 1 containing:
7; CHECK-LABEL: irce: in function test_03: constrained Loop at depth 1 containing:
8; CHECK-LABEL: irce: in function test_04: constrained Loop at depth 1 containing:
9; CHECK-LABEL: irce: in function test_05: constrained Loop at depth 1 containing:
10
11; This test used to demonstrate a miscompile: the outer loop's IV iterates in
12; range of [2, 400) and the range check is done against value 331. Due to a bug
13; in range intersection IRCE manages to eliminate the range check without
14; inserting a postloop, which is incorrect. We treat the range of this test as
15; an unsigned range and are able to intersect ranges correctly and insert a
16; postloop.
17
18define void @test_01() {
19; CHECK-LABEL: define void @test_01() {
20; CHECK-NEXT:  entry:
21; CHECK-NEXT:    br i1 true, label [[LOOP_HEADER_PREHEADER:%.*]], label [[MAIN_PSEUDO_EXIT:%.*]]
22; CHECK:       loop_header.preheader:
23; CHECK-NEXT:    br label [[LOOP_HEADER:%.*]]
24; CHECK:       loop_header:
25; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ], [ 2, [[LOOP_HEADER_PREHEADER]] ]
26; CHECK-NEXT:    [[IV_PREV:%.*]] = phi i32 [ [[IV]], [[LOOP_LATCH]] ], [ 1, [[LOOP_HEADER_PREHEADER]] ]
27; CHECK-NEXT:    [[TMP2:%.*]] = icmp sgt i32 [[IV_PREV]], -1
28; CHECK-NEXT:    br i1 true, label [[LOOP_HEADER_SPLIT_US:%.*]], label [[EXIT_LOOPEXIT1:%.*]]
29; CHECK:       loop_header.split.us:
30; CHECK-NEXT:    br label [[INNER_LOOP:%.*]]
31; CHECK:       inner_loop:
32; CHECK-NEXT:    [[INNER_IV:%.*]] = phi i32 [ 1, [[LOOP_HEADER_SPLIT_US]] ], [ [[INNER_IV_NEXT:%.*]], [[INNER_LOOP]] ]
33; CHECK-NEXT:    [[INNER_IV_NEXT]] = add nuw nsw i32 [[INNER_IV]], 1
34; CHECK-NEXT:    [[INNER_COND:%.*]] = icmp ult i32 [[INNER_IV_NEXT]], 31
35; CHECK-NEXT:    br i1 [[INNER_COND]], label [[INNER_LOOP]], label [[RANGE_CHECK_BLOCK:%.*]]
36; CHECK:       exit.loopexit:
37; CHECK-NEXT:    br label [[EXIT:%.*]]
38; CHECK:       exit.loopexit1:
39; CHECK-NEXT:    br label [[EXIT]]
40; CHECK:       exit:
41; CHECK-NEXT:    ret void
42; CHECK:       range_check_block:
43; CHECK-NEXT:    [[RANGE_CHECK:%.*]] = icmp slt i32 [[IV]], 331
44; CHECK-NEXT:    br i1 true, label [[LOOP_LATCH]], label [[DEOPT_LOOPEXIT2:%.*]]
45; CHECK:       loop_latch:
46; CHECK-NEXT:    [[IV_NEXT]] = add i32 [[IV]], 1
47; CHECK-NEXT:    [[LOOP_COND:%.*]] = icmp ult i32 [[IV_NEXT]], 400
48; CHECK-NEXT:    [[TMP0:%.*]] = icmp ult i32 [[IV_NEXT]], 331
49; CHECK-NEXT:    br i1 [[TMP0]], label [[LOOP_HEADER]], label [[MAIN_EXIT_SELECTOR:%.*]]
50; CHECK:       main.exit.selector:
51; CHECK-NEXT:    [[IV_NEXT_LCSSA:%.*]] = phi i32 [ [[IV_NEXT]], [[LOOP_LATCH]] ]
52; CHECK-NEXT:    [[IV_LCSSA:%.*]] = phi i32 [ [[IV]], [[LOOP_LATCH]] ]
53; CHECK-NEXT:    [[TMP1:%.*]] = icmp ult i32 [[IV_NEXT_LCSSA]], 400
54; CHECK-NEXT:    br i1 [[TMP1]], label [[MAIN_PSEUDO_EXIT]], label [[EXIT]]
55; CHECK:       main.pseudo.exit:
56; CHECK-NEXT:    [[IV_COPY:%.*]] = phi i32 [ 2, [[ENTRY:%.*]] ], [ [[IV_NEXT_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
57; CHECK-NEXT:    [[IV_PREV_COPY:%.*]] = phi i32 [ 1, [[ENTRY]] ], [ [[IV_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
58; CHECK-NEXT:    [[INDVAR_END:%.*]] = phi i32 [ 2, [[ENTRY]] ], [ [[IV_NEXT_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
59; CHECK-NEXT:    br label [[POSTLOOP:%.*]]
60; CHECK:       deopt.loopexit:
61; CHECK-NEXT:    br label [[DEOPT:%.*]]
62; CHECK:       deopt.loopexit2:
63; CHECK-NEXT:    br label [[DEOPT]]
64; CHECK:       deopt:
65; CHECK-NEXT:    ret void
66; CHECK:       postloop:
67; CHECK-NEXT:    br label [[LOOP_HEADER_POSTLOOP:%.*]]
68; CHECK:       loop_header.postloop:
69; CHECK-NEXT:    [[IV_POSTLOOP:%.*]] = phi i32 [ [[IV_COPY]], [[POSTLOOP]] ], [ [[IV_NEXT_POSTLOOP:%.*]], [[LOOP_LATCH_POSTLOOP:%.*]] ]
70; CHECK-NEXT:    [[IV_PREV_POSTLOOP:%.*]] = phi i32 [ [[IV_PREV_COPY]], [[POSTLOOP]] ], [ [[IV_POSTLOOP]], [[LOOP_LATCH_POSTLOOP]] ]
71; CHECK-NEXT:    [[TMP2_POSTLOOP:%.*]] = icmp sgt i32 [[IV_PREV_POSTLOOP]], -1
72; CHECK-NEXT:    br i1 [[TMP2_POSTLOOP]], label [[LOOP_HEADER_SPLIT_US_POSTLOOP:%.*]], label [[EXIT_LOOPEXIT:%.*]]
73; CHECK:       loop_header.split.us.postloop:
74; CHECK-NEXT:    br label [[INNER_LOOP_POSTLOOP:%.*]]
75; CHECK:       inner_loop.postloop:
76; CHECK-NEXT:    [[INNER_IV_POSTLOOP:%.*]] = phi i32 [ 1, [[LOOP_HEADER_SPLIT_US_POSTLOOP]] ], [ [[INNER_IV_NEXT_POSTLOOP:%.*]], [[INNER_LOOP_POSTLOOP]] ]
77; CHECK-NEXT:    [[INNER_IV_NEXT_POSTLOOP]] = add nuw nsw i32 [[INNER_IV_POSTLOOP]], 1
78; CHECK-NEXT:    [[INNER_COND_POSTLOOP:%.*]] = icmp ult i32 [[INNER_IV_NEXT_POSTLOOP]], 31
79; CHECK-NEXT:    br i1 [[INNER_COND_POSTLOOP]], label [[INNER_LOOP_POSTLOOP]], label [[RANGE_CHECK_BLOCK_POSTLOOP:%.*]]
80; CHECK:       range_check_block.postloop:
81; CHECK-NEXT:    [[RANGE_CHECK_POSTLOOP:%.*]] = icmp slt i32 [[IV_POSTLOOP]], 331
82; CHECK-NEXT:    br i1 [[RANGE_CHECK_POSTLOOP]], label [[LOOP_LATCH_POSTLOOP]], label [[DEOPT_LOOPEXIT:%.*]]
83; CHECK:       loop_latch.postloop:
84; CHECK-NEXT:    [[IV_NEXT_POSTLOOP]] = add i32 [[IV_POSTLOOP]], 1
85; CHECK-NEXT:    [[LOOP_COND_POSTLOOP:%.*]] = icmp ult i32 [[IV_NEXT_POSTLOOP]], 400
86; CHECK-NEXT:    br i1 [[LOOP_COND_POSTLOOP]], label [[LOOP_HEADER_POSTLOOP]], label [[EXIT_LOOPEXIT]], !llvm.loop [[LOOP0:![0-9]+]], !loop_constrainer.loop.clone [[META5:![0-9]+]]
87;
88
89entry:
90  br label %loop_header
91
92loop_header:                            ; preds = %loop_latch, %entry
93  %iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
94  %iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
95  %tmp2 = icmp sgt i32 %iv.prev, -1
96  br i1 %tmp2, label %loop_header.split.us, label %exit
97
98loop_header.split.us:                   ; preds = %loop_header
99  br label %inner_loop
100
101inner_loop:                                   ; preds = %inner_loop, %loop_header.split.us
102  %inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
103  %inner_iv_next = add nuw nsw i32 %inner_iv, 1
104  %inner_cond = icmp ult i32 %inner_iv_next, 31
105  br i1 %inner_cond, label %inner_loop, label %range_check_block
106
107exit:                                            ; preds = %loop_latch, %loop_header
108  ret void
109
110range_check_block:                                          ; preds = %inner_loop
111  %range_check = icmp slt i32 %iv, 331
112  br i1 %range_check, label %loop_latch, label %deopt
113
114loop_latch:                                         ; preds = %range_check_block
115  %iv_next = add i32 %iv, 1
116  %loop_cond = icmp ult i32 %iv_next, 400
117  br i1 %loop_cond, label %loop_header, label %exit
118
119deopt:                                          ; preds = %range_check_block
120  ret void
121}
122
123; Similar to test_01, but here the range check is done against 450. No postloop
124; is required.
125
126define void @test_02() {
127; CHECK-LABEL: define void @test_02() {
128; CHECK-NEXT:  entry:
129; CHECK-NEXT:    br label [[LOOP_HEADER:%.*]]
130; CHECK:       loop_header:
131; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ 2, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ]
132; CHECK-NEXT:    [[IV_PREV:%.*]] = phi i32 [ 1, [[ENTRY]] ], [ [[IV]], [[LOOP_LATCH]] ]
133; CHECK-NEXT:    [[TMP2:%.*]] = icmp sgt i32 [[IV_PREV]], -1
134; CHECK-NEXT:    br i1 true, label [[LOOP_HEADER_SPLIT_US:%.*]], label [[EXIT:%.*]]
135; CHECK:       loop_header.split.us:
136; CHECK-NEXT:    br label [[INNER_LOOP:%.*]]
137; CHECK:       inner_loop:
138; CHECK-NEXT:    [[INNER_IV:%.*]] = phi i32 [ 1, [[LOOP_HEADER_SPLIT_US]] ], [ [[INNER_IV_NEXT:%.*]], [[INNER_LOOP]] ]
139; CHECK-NEXT:    [[INNER_IV_NEXT]] = add nuw nsw i32 [[INNER_IV]], 1
140; CHECK-NEXT:    [[INNER_COND:%.*]] = icmp ult i32 [[INNER_IV_NEXT]], 31
141; CHECK-NEXT:    br i1 [[INNER_COND]], label [[INNER_LOOP]], label [[RANGE_CHECK_BLOCK:%.*]]
142; CHECK:       exit:
143; CHECK-NEXT:    ret void
144; CHECK:       range_check_block:
145; CHECK-NEXT:    [[RANGE_CHECK:%.*]] = icmp slt i32 [[IV]], 450
146; CHECK-NEXT:    br i1 true, label [[LOOP_LATCH]], label [[DEOPT:%.*]]
147; CHECK:       loop_latch:
148; CHECK-NEXT:    [[IV_NEXT]] = add i32 [[IV]], 1
149; CHECK-NEXT:    [[LOOP_COND:%.*]] = icmp ult i32 [[IV_NEXT]], 400
150; CHECK-NEXT:    br i1 [[LOOP_COND]], label [[LOOP_HEADER]], label [[EXIT]]
151; CHECK:       deopt:
152; CHECK-NEXT:    ret void
153;
154
155entry:
156  br label %loop_header
157
158loop_header:                            ; preds = %loop_latch, %entry
159  %iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
160  %iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
161  %tmp2 = icmp sgt i32 %iv.prev, -1
162  br i1 %tmp2, label %loop_header.split.us, label %exit
163
164loop_header.split.us:                   ; preds = %loop_header
165  br label %inner_loop
166
167inner_loop:                                   ; preds = %inner_loop, %loop_header.split.us
168  %inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
169  %inner_iv_next = add nuw nsw i32 %inner_iv, 1
170  %inner_cond = icmp ult i32 %inner_iv_next, 31
171  br i1 %inner_cond, label %inner_loop, label %range_check_block
172
173exit:                                            ; preds = %loop_latch, %loop_header
174  ret void
175
176range_check_block:                                          ; preds = %inner_loop
177  %range_check = icmp slt i32 %iv, 450
178  br i1 %range_check, label %loop_latch, label %deopt
179
180loop_latch:                                         ; preds = %range_check_block
181  %iv_next = add i32 %iv, 1
182  %loop_cond = icmp ult i32 %iv_next, 400
183  br i1 %loop_cond, label %loop_header, label %exit
184
185deopt:                                          ; preds = %range_check_block
186  ret void
187}
188
189; Range check is made against 0, so the safe iteration range is empty. IRCE
190; should not apply to the inner loop. The condition %tmp2 can be eliminated.
191
192define void @test_03() {
193; CHECK-LABEL: define void @test_03() {
194; CHECK-NEXT:  entry:
195; CHECK-NEXT:    br label [[LOOP_HEADER:%.*]]
196; CHECK:       loop_header:
197; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ 2, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ]
198; CHECK-NEXT:    [[IV_PREV:%.*]] = phi i32 [ 1, [[ENTRY]] ], [ [[IV]], [[LOOP_LATCH]] ]
199; CHECK-NEXT:    [[TMP2:%.*]] = icmp sgt i32 [[IV_PREV]], -1
200; CHECK-NEXT:    br i1 true, label [[LOOP_HEADER_SPLIT_US:%.*]], label [[EXIT:%.*]]
201; CHECK:       loop_header.split.us:
202; CHECK-NEXT:    br label [[INNER_LOOP:%.*]]
203; CHECK:       inner_loop:
204; CHECK-NEXT:    [[INNER_IV:%.*]] = phi i32 [ 1, [[LOOP_HEADER_SPLIT_US]] ], [ [[INNER_IV_NEXT:%.*]], [[INNER_LOOP]] ]
205; CHECK-NEXT:    [[INNER_IV_NEXT]] = add nuw nsw i32 [[INNER_IV]], 1
206; CHECK-NEXT:    [[INNER_COND:%.*]] = icmp ult i32 [[INNER_IV_NEXT]], 31
207; CHECK-NEXT:    br i1 [[INNER_COND]], label [[INNER_LOOP]], label [[RANGE_CHECK_BLOCK:%.*]]
208; CHECK:       exit:
209; CHECK-NEXT:    ret void
210; CHECK:       range_check_block:
211; CHECK-NEXT:    [[RANGE_CHECK:%.*]] = icmp slt i32 [[IV]], 0
212; CHECK-NEXT:    br i1 [[RANGE_CHECK]], label [[LOOP_LATCH]], label [[DEOPT:%.*]]
213; CHECK:       loop_latch:
214; CHECK-NEXT:    [[IV_NEXT]] = add i32 [[IV]], 1
215; CHECK-NEXT:    [[LOOP_COND:%.*]] = icmp ult i32 [[IV_NEXT]], 400
216; CHECK-NEXT:    br i1 [[LOOP_COND]], label [[LOOP_HEADER]], label [[EXIT]]
217; CHECK:       deopt:
218; CHECK-NEXT:    ret void
219;
220
221entry:
222  br label %loop_header
223
224loop_header:                            ; preds = %loop_latch, %entry
225  %iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
226  %iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
227  %tmp2 = icmp sgt i32 %iv.prev, -1
228  br i1 %tmp2, label %loop_header.split.us, label %exit
229
230loop_header.split.us:                   ; preds = %loop_header
231  br label %inner_loop
232
233inner_loop:                                   ; preds = %inner_loop, %loop_header.split.us
234  %inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
235  %inner_iv_next = add nuw nsw i32 %inner_iv, 1
236  %inner_cond = icmp ult i32 %inner_iv_next, 31
237  br i1 %inner_cond, label %inner_loop, label %range_check_block
238
239exit:                                            ; preds = %loop_latch, %loop_header
240  ret void
241
242range_check_block:                                          ; preds = %inner_loop
243  %range_check = icmp slt i32 %iv, 0
244  br i1 %range_check, label %loop_latch, label %deopt
245
246loop_latch:                                         ; preds = %range_check_block
247  %iv_next = add i32 %iv, 1
248  %loop_cond = icmp ult i32 %iv_next, 400
249  br i1 %loop_cond, label %loop_header, label %exit
250
251deopt:                                          ; preds = %range_check_block
252  ret void
253}
254
255; We can also properly eliminate range check against %n which is not always
256; known positive.
257
258define void @test_04(ptr %p) {
259; CHECK-LABEL: define void @test_04
260; CHECK-SAME: (ptr [[P:%.*]]) {
261; CHECK-NEXT:  entry:
262; CHECK-NEXT:    [[N:%.*]] = load i32, ptr [[P]], align 4
263; CHECK-NEXT:    [[SMIN:%.*]] = call i32 @llvm.smin.i32(i32 [[N]], i32 0)
264; CHECK-NEXT:    [[TMP0:%.*]] = sub i32 [[N]], [[SMIN]]
265; CHECK-NEXT:    [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[SMIN]], i32 -1)
266; CHECK-NEXT:    [[TMP1:%.*]] = add nsw i32 [[SMAX]], 1
267; CHECK-NEXT:    [[TMP2:%.*]] = mul i32 [[TMP0]], [[TMP1]]
268; CHECK-NEXT:    [[UMIN:%.*]] = call i32 @llvm.umin.i32(i32 [[TMP2]], i32 400)
269; CHECK-NEXT:    [[EXIT_MAINLOOP_AT:%.*]] = call i32 @llvm.umax.i32(i32 [[UMIN]], i32 2)
270; CHECK-NEXT:    [[TMP3:%.*]] = icmp ult i32 2, [[EXIT_MAINLOOP_AT]]
271; CHECK-NEXT:    br i1 [[TMP3]], label [[LOOP_HEADER_PREHEADER:%.*]], label [[MAIN_PSEUDO_EXIT:%.*]]
272; CHECK:       loop_header.preheader:
273; CHECK-NEXT:    br label [[LOOP_HEADER:%.*]]
274; CHECK:       loop_header:
275; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ], [ 2, [[LOOP_HEADER_PREHEADER]] ]
276; CHECK-NEXT:    [[IV_PREV:%.*]] = phi i32 [ [[IV]], [[LOOP_LATCH]] ], [ 1, [[LOOP_HEADER_PREHEADER]] ]
277; CHECK-NEXT:    [[TMP2:%.*]] = icmp sgt i32 [[IV_PREV]], -1
278; CHECK-NEXT:    br i1 true, label [[LOOP_HEADER_SPLIT_US:%.*]], label [[EXIT_LOOPEXIT1:%.*]]
279; CHECK:       loop_header.split.us:
280; CHECK-NEXT:    br label [[INNER_LOOP:%.*]]
281; CHECK:       inner_loop:
282; CHECK-NEXT:    [[INNER_IV:%.*]] = phi i32 [ 1, [[LOOP_HEADER_SPLIT_US]] ], [ [[INNER_IV_NEXT:%.*]], [[INNER_LOOP]] ]
283; CHECK-NEXT:    [[INNER_IV_NEXT]] = add nuw nsw i32 [[INNER_IV]], 1
284; CHECK-NEXT:    [[INNER_COND:%.*]] = icmp ult i32 [[INNER_IV_NEXT]], 31
285; CHECK-NEXT:    br i1 [[INNER_COND]], label [[INNER_LOOP]], label [[RANGE_CHECK_BLOCK:%.*]]
286; CHECK:       exit.loopexit:
287; CHECK-NEXT:    br label [[EXIT:%.*]]
288; CHECK:       exit.loopexit1:
289; CHECK-NEXT:    br label [[EXIT]]
290; CHECK:       exit:
291; CHECK-NEXT:    ret void
292; CHECK:       range_check_block:
293; CHECK-NEXT:    [[RANGE_CHECK:%.*]] = icmp slt i32 [[IV]], [[N]]
294; CHECK-NEXT:    br i1 true, label [[LOOP_LATCH]], label [[DEOPT_LOOPEXIT2:%.*]]
295; CHECK:       loop_latch:
296; CHECK-NEXT:    [[IV_NEXT]] = add i32 [[IV]], 1
297; CHECK-NEXT:    [[LOOP_COND:%.*]] = icmp ult i32 [[IV_NEXT]], 400
298; CHECK-NEXT:    [[TMP4:%.*]] = icmp ult i32 [[IV_NEXT]], [[EXIT_MAINLOOP_AT]]
299; CHECK-NEXT:    br i1 [[TMP4]], label [[LOOP_HEADER]], label [[MAIN_EXIT_SELECTOR:%.*]]
300; CHECK:       main.exit.selector:
301; CHECK-NEXT:    [[IV_NEXT_LCSSA:%.*]] = phi i32 [ [[IV_NEXT]], [[LOOP_LATCH]] ]
302; CHECK-NEXT:    [[IV_LCSSA:%.*]] = phi i32 [ [[IV]], [[LOOP_LATCH]] ]
303; CHECK-NEXT:    [[TMP5:%.*]] = icmp ult i32 [[IV_NEXT_LCSSA]], 400
304; CHECK-NEXT:    br i1 [[TMP5]], label [[MAIN_PSEUDO_EXIT]], label [[EXIT]]
305; CHECK:       main.pseudo.exit:
306; CHECK-NEXT:    [[IV_COPY:%.*]] = phi i32 [ 2, [[ENTRY:%.*]] ], [ [[IV_NEXT_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
307; CHECK-NEXT:    [[IV_PREV_COPY:%.*]] = phi i32 [ 1, [[ENTRY]] ], [ [[IV_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
308; CHECK-NEXT:    [[INDVAR_END:%.*]] = phi i32 [ 2, [[ENTRY]] ], [ [[IV_NEXT_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
309; CHECK-NEXT:    br label [[POSTLOOP:%.*]]
310; CHECK:       deopt.loopexit:
311; CHECK-NEXT:    br label [[DEOPT:%.*]]
312; CHECK:       deopt.loopexit2:
313; CHECK-NEXT:    br label [[DEOPT]]
314; CHECK:       deopt:
315; CHECK-NEXT:    ret void
316; CHECK:       postloop:
317; CHECK-NEXT:    br label [[LOOP_HEADER_POSTLOOP:%.*]]
318; CHECK:       loop_header.postloop:
319; CHECK-NEXT:    [[IV_POSTLOOP:%.*]] = phi i32 [ [[IV_COPY]], [[POSTLOOP]] ], [ [[IV_NEXT_POSTLOOP:%.*]], [[LOOP_LATCH_POSTLOOP:%.*]] ]
320; CHECK-NEXT:    [[IV_PREV_POSTLOOP:%.*]] = phi i32 [ [[IV_PREV_COPY]], [[POSTLOOP]] ], [ [[IV_POSTLOOP]], [[LOOP_LATCH_POSTLOOP]] ]
321; CHECK-NEXT:    [[TMP2_POSTLOOP:%.*]] = icmp sgt i32 [[IV_PREV_POSTLOOP]], -1
322; CHECK-NEXT:    br i1 [[TMP2_POSTLOOP]], label [[LOOP_HEADER_SPLIT_US_POSTLOOP:%.*]], label [[EXIT_LOOPEXIT:%.*]]
323; CHECK:       loop_header.split.us.postloop:
324; CHECK-NEXT:    br label [[INNER_LOOP_POSTLOOP:%.*]]
325; CHECK:       inner_loop.postloop:
326; CHECK-NEXT:    [[INNER_IV_POSTLOOP:%.*]] = phi i32 [ 1, [[LOOP_HEADER_SPLIT_US_POSTLOOP]] ], [ [[INNER_IV_NEXT_POSTLOOP:%.*]], [[INNER_LOOP_POSTLOOP]] ]
327; CHECK-NEXT:    [[INNER_IV_NEXT_POSTLOOP]] = add nuw nsw i32 [[INNER_IV_POSTLOOP]], 1
328; CHECK-NEXT:    [[INNER_COND_POSTLOOP:%.*]] = icmp ult i32 [[INNER_IV_NEXT_POSTLOOP]], 31
329; CHECK-NEXT:    br i1 [[INNER_COND_POSTLOOP]], label [[INNER_LOOP_POSTLOOP]], label [[RANGE_CHECK_BLOCK_POSTLOOP:%.*]]
330; CHECK:       range_check_block.postloop:
331; CHECK-NEXT:    [[RANGE_CHECK_POSTLOOP:%.*]] = icmp slt i32 [[IV_POSTLOOP]], [[N]]
332; CHECK-NEXT:    br i1 [[RANGE_CHECK_POSTLOOP]], label [[LOOP_LATCH_POSTLOOP]], label [[DEOPT_LOOPEXIT:%.*]]
333; CHECK:       loop_latch.postloop:
334; CHECK-NEXT:    [[IV_NEXT_POSTLOOP]] = add i32 [[IV_POSTLOOP]], 1
335; CHECK-NEXT:    [[LOOP_COND_POSTLOOP:%.*]] = icmp ult i32 [[IV_NEXT_POSTLOOP]], 400
336; CHECK-NEXT:    br i1 [[LOOP_COND_POSTLOOP]], label [[LOOP_HEADER_POSTLOOP]], label [[EXIT_LOOPEXIT]], !llvm.loop [[LOOP6:![0-9]+]], !loop_constrainer.loop.clone [[META5]]
337;
338
339entry:
340  %n = load i32, ptr %p
341  br label %loop_header
342
343loop_header:                            ; preds = %loop_latch, %entry
344  %iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
345  %iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
346  %tmp2 = icmp sgt i32 %iv.prev, -1
347  br i1 %tmp2, label %loop_header.split.us, label %exit
348
349loop_header.split.us:                   ; preds = %loop_header
350  br label %inner_loop
351
352inner_loop:                                   ; preds = %inner_loop, %loop_header.split.us
353  %inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
354  %inner_iv_next = add nuw nsw i32 %inner_iv, 1
355  %inner_cond = icmp ult i32 %inner_iv_next, 31
356  br i1 %inner_cond, label %inner_loop, label %range_check_block
357
358exit:                                            ; preds = %loop_latch, %loop_header
359  ret void
360
361range_check_block:                                          ; preds = %inner_loop
362  %range_check = icmp slt i32 %iv, %n
363  br i1 %range_check, label %loop_latch, label %deopt
364
365loop_latch:                                         ; preds = %range_check_block
366  %iv_next = add i32 %iv, 1
367  %loop_cond = icmp ult i32 %iv_next, 400
368  br i1 %loop_cond, label %loop_header, label %exit
369
370deopt:                                          ; preds = %range_check_block
371  ret void
372}
373
374; Same as test_04, but range guarantees that %n is positive. So we can safely
375; intersect ranges (with insertion of postloop).
376
377define void @test_05(ptr %p) {
378; CHECK-LABEL: define void @test_05
379; CHECK-SAME: (ptr [[P:%.*]]) {
380; CHECK-NEXT:  entry:
381; CHECK-NEXT:    [[N:%.*]] = load i32, ptr [[P]], align 4, !range [[RNG7:![0-9]+]]
382; CHECK-NEXT:    [[EXIT_MAINLOOP_AT:%.*]] = call i32 @llvm.umax.i32(i32 [[N]], i32 2)
383; CHECK-NEXT:    [[TMP0:%.*]] = icmp ult i32 2, [[EXIT_MAINLOOP_AT]]
384; CHECK-NEXT:    br i1 [[TMP0]], label [[LOOP_HEADER_PREHEADER:%.*]], label [[MAIN_PSEUDO_EXIT:%.*]]
385; CHECK:       loop_header.preheader:
386; CHECK-NEXT:    br label [[LOOP_HEADER:%.*]]
387; CHECK:       loop_header:
388; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ], [ 2, [[LOOP_HEADER_PREHEADER]] ]
389; CHECK-NEXT:    [[IV_PREV:%.*]] = phi i32 [ [[IV]], [[LOOP_LATCH]] ], [ 1, [[LOOP_HEADER_PREHEADER]] ]
390; CHECK-NEXT:    [[TMP2:%.*]] = icmp sgt i32 [[IV_PREV]], -1
391; CHECK-NEXT:    br i1 true, label [[LOOP_HEADER_SPLIT_US:%.*]], label [[EXIT_LOOPEXIT1:%.*]]
392; CHECK:       loop_header.split.us:
393; CHECK-NEXT:    br label [[INNER_LOOP:%.*]]
394; CHECK:       inner_loop:
395; CHECK-NEXT:    [[INNER_IV:%.*]] = phi i32 [ 1, [[LOOP_HEADER_SPLIT_US]] ], [ [[INNER_IV_NEXT:%.*]], [[INNER_LOOP]] ]
396; CHECK-NEXT:    [[INNER_IV_NEXT]] = add nuw nsw i32 [[INNER_IV]], 1
397; CHECK-NEXT:    [[INNER_COND:%.*]] = icmp ult i32 [[INNER_IV_NEXT]], 31
398; CHECK-NEXT:    br i1 [[INNER_COND]], label [[INNER_LOOP]], label [[RANGE_CHECK_BLOCK:%.*]]
399; CHECK:       exit.loopexit:
400; CHECK-NEXT:    br label [[EXIT:%.*]]
401; CHECK:       exit.loopexit1:
402; CHECK-NEXT:    br label [[EXIT]]
403; CHECK:       exit:
404; CHECK-NEXT:    ret void
405; CHECK:       range_check_block:
406; CHECK-NEXT:    [[RANGE_CHECK:%.*]] = icmp slt i32 [[IV]], [[N]]
407; CHECK-NEXT:    br i1 true, label [[LOOP_LATCH]], label [[DEOPT_LOOPEXIT2:%.*]]
408; CHECK:       loop_latch:
409; CHECK-NEXT:    [[IV_NEXT]] = add i32 [[IV]], 1
410; CHECK-NEXT:    [[LOOP_COND:%.*]] = icmp ult i32 [[IV_NEXT]], 400
411; CHECK-NEXT:    [[TMP1:%.*]] = icmp ult i32 [[IV_NEXT]], [[EXIT_MAINLOOP_AT]]
412; CHECK-NEXT:    br i1 [[TMP1]], label [[LOOP_HEADER]], label [[MAIN_EXIT_SELECTOR:%.*]]
413; CHECK:       main.exit.selector:
414; CHECK-NEXT:    [[IV_NEXT_LCSSA:%.*]] = phi i32 [ [[IV_NEXT]], [[LOOP_LATCH]] ]
415; CHECK-NEXT:    [[IV_LCSSA:%.*]] = phi i32 [ [[IV]], [[LOOP_LATCH]] ]
416; CHECK-NEXT:    [[TMP2:%.*]] = icmp ult i32 [[IV_NEXT_LCSSA]], 400
417; CHECK-NEXT:    br i1 [[TMP2]], label [[MAIN_PSEUDO_EXIT]], label [[EXIT]]
418; CHECK:       main.pseudo.exit:
419; CHECK-NEXT:    [[IV_COPY:%.*]] = phi i32 [ 2, [[ENTRY:%.*]] ], [ [[IV_NEXT_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
420; CHECK-NEXT:    [[IV_PREV_COPY:%.*]] = phi i32 [ 1, [[ENTRY]] ], [ [[IV_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
421; CHECK-NEXT:    [[INDVAR_END:%.*]] = phi i32 [ 2, [[ENTRY]] ], [ [[IV_NEXT_LCSSA]], [[MAIN_EXIT_SELECTOR]] ]
422; CHECK-NEXT:    br label [[POSTLOOP:%.*]]
423; CHECK:       deopt.loopexit:
424; CHECK-NEXT:    br label [[DEOPT:%.*]]
425; CHECK:       deopt.loopexit2:
426; CHECK-NEXT:    br label [[DEOPT]]
427; CHECK:       deopt:
428; CHECK-NEXT:    ret void
429; CHECK:       postloop:
430; CHECK-NEXT:    br label [[LOOP_HEADER_POSTLOOP:%.*]]
431; CHECK:       loop_header.postloop:
432; CHECK-NEXT:    [[IV_POSTLOOP:%.*]] = phi i32 [ [[IV_COPY]], [[POSTLOOP]] ], [ [[IV_NEXT_POSTLOOP:%.*]], [[LOOP_LATCH_POSTLOOP:%.*]] ]
433; CHECK-NEXT:    [[IV_PREV_POSTLOOP:%.*]] = phi i32 [ [[IV_PREV_COPY]], [[POSTLOOP]] ], [ [[IV_POSTLOOP]], [[LOOP_LATCH_POSTLOOP]] ]
434; CHECK-NEXT:    [[TMP2_POSTLOOP:%.*]] = icmp sgt i32 [[IV_PREV_POSTLOOP]], -1
435; CHECK-NEXT:    br i1 [[TMP2_POSTLOOP]], label [[LOOP_HEADER_SPLIT_US_POSTLOOP:%.*]], label [[EXIT_LOOPEXIT:%.*]]
436; CHECK:       loop_header.split.us.postloop:
437; CHECK-NEXT:    br label [[INNER_LOOP_POSTLOOP:%.*]]
438; CHECK:       inner_loop.postloop:
439; CHECK-NEXT:    [[INNER_IV_POSTLOOP:%.*]] = phi i32 [ 1, [[LOOP_HEADER_SPLIT_US_POSTLOOP]] ], [ [[INNER_IV_NEXT_POSTLOOP:%.*]], [[INNER_LOOP_POSTLOOP]] ]
440; CHECK-NEXT:    [[INNER_IV_NEXT_POSTLOOP]] = add nuw nsw i32 [[INNER_IV_POSTLOOP]], 1
441; CHECK-NEXT:    [[INNER_COND_POSTLOOP:%.*]] = icmp ult i32 [[INNER_IV_NEXT_POSTLOOP]], 31
442; CHECK-NEXT:    br i1 [[INNER_COND_POSTLOOP]], label [[INNER_LOOP_POSTLOOP]], label [[RANGE_CHECK_BLOCK_POSTLOOP:%.*]]
443; CHECK:       range_check_block.postloop:
444; CHECK-NEXT:    [[RANGE_CHECK_POSTLOOP:%.*]] = icmp slt i32 [[IV_POSTLOOP]], [[N]]
445; CHECK-NEXT:    br i1 [[RANGE_CHECK_POSTLOOP]], label [[LOOP_LATCH_POSTLOOP]], label [[DEOPT_LOOPEXIT:%.*]]
446; CHECK:       loop_latch.postloop:
447; CHECK-NEXT:    [[IV_NEXT_POSTLOOP]] = add i32 [[IV_POSTLOOP]], 1
448; CHECK-NEXT:    [[LOOP_COND_POSTLOOP:%.*]] = icmp ult i32 [[IV_NEXT_POSTLOOP]], 400
449; CHECK-NEXT:    br i1 [[LOOP_COND_POSTLOOP]], label [[LOOP_HEADER_POSTLOOP]], label [[EXIT_LOOPEXIT]], !llvm.loop [[LOOP8:![0-9]+]], !loop_constrainer.loop.clone [[META5]]
450;
451
452entry:
453  %n = load i32, ptr %p, !range !0
454  br label %loop_header
455
456loop_header:                            ; preds = %loop_latch, %entry
457  %iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
458  %iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
459  %tmp2 = icmp sgt i32 %iv.prev, -1
460  br i1 %tmp2, label %loop_header.split.us, label %exit
461
462loop_header.split.us:                   ; preds = %loop_header
463  br label %inner_loop
464
465inner_loop:                                   ; preds = %inner_loop, %loop_header.split.us
466  %inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
467  %inner_iv_next = add nuw nsw i32 %inner_iv, 1
468  %inner_cond = icmp ult i32 %inner_iv_next, 31
469  br i1 %inner_cond, label %inner_loop, label %range_check_block
470
471exit:                                            ; preds = %loop_latch, %loop_header
472  ret void
473
474range_check_block:                                          ; preds = %inner_loop
475  %range_check = icmp slt i32 %iv, %n
476  br i1 %range_check, label %loop_latch, label %deopt
477
478loop_latch:                                         ; preds = %range_check_block
479  %iv_next = add i32 %iv, 1
480  %loop_cond = icmp ult i32 %iv_next, 400
481  br i1 %loop_cond, label %loop_header, label %exit
482
483deopt:                                          ; preds = %range_check_block
484  ret void
485}
486
487!0 = !{i32 0, i32 50}
488;.
489; CHECK: [[LOOP0]] = distinct !{[[LOOP0]], [[META1:![0-9]+]], [[META2:![0-9]+]], [[META3:![0-9]+]], [[META4:![0-9]+]]}
490; CHECK: [[META1]] = !{!"llvm.loop.unroll.disable"}
491; CHECK: [[META2]] = !{!"llvm.loop.vectorize.enable", i1 false}
492; CHECK: [[META3]] = !{!"llvm.loop.licm_versioning.disable"}
493; CHECK: [[META4]] = !{!"llvm.loop.distribute.enable", i1 false}
494; CHECK: [[META5]] = !{}
495; CHECK: [[LOOP6]] = distinct !{[[LOOP6]], [[META1]], [[META2]], [[META3]], [[META4]]}
496; CHECK: [[RNG7]] = !{i32 0, i32 50}
497; CHECK: [[LOOP8]] = distinct !{[[LOOP8]], [[META1]], [[META2]], [[META3]], [[META4]]}
498;.
499