; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=indvars -S | FileCheck %s
; PR31181: It may be necessary to drop nuw/nsw flags when moving from a
; pre-increment comparison to a post-increment comparison.
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
@a = global i32 0
define i32 @test_drop_nuw() {
; CHECK-LABEL: @test_drop_nuw(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[STOREMERGE:%.*]] = phi i32 [ -2, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[LOOP]] ]
; CHECK-NEXT: store i32 [[STOREMERGE]], ptr @a, align 4
; CHECK-NEXT: [[INC]] = add nsw i32 [[STOREMERGE]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[INC]], 0
; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: ret i32 0
;
entry:
br label %loop
loop:
%storemerge = phi i32 [ -2, %entry ], [ %inc, %loop ]
store i32 %storemerge, ptr @a
%cmp = icmp slt i32 %storemerge, -1
%inc = add nuw nsw i32 %storemerge, 1
br i1 %cmp, label %loop, label %exit
exit:
ret i32 0
}
define i32 @test_drop_nsw() {
; CHECK-LABEL: @test_drop_nsw(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[STOREMERGE:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[LOOP]] ]
; CHECK-NEXT: store i32 [[STOREMERGE]], ptr @a, align 4
; CHECK-NEXT: [[INC]] = add nuw i32 [[STOREMERGE]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[INC]], -2147483648
; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: ret i32 0
;
entry:
br label %loop
loop:
%storemerge = phi i32 [ 0, %entry ], [ %inc, %loop ]
store i32 %storemerge, ptr @a
%cmp = icmp ult i32 %storemerge, 2147483647
%inc = add nuw nsw i32 %storemerge, 1
br i1 %cmp, label %loop, label %exit
exit:
ret i32 0
}
define i32 @test_no_drop_nuw() {
; CHECK-LABEL: @test_no_drop_nuw(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[STOREMERGE:%.*]] = phi i32 [ -3, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[LOOP]] ]
; CHECK-NEXT: store i32 [[STOREMERGE]], ptr @a, align 4
; CHECK-NEXT: [[INC]] = add nuw nsw i32 [[STOREMERGE]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[INC]], -1
; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: ret i32 0
;
entry:
br label %loop
loop:
%storemerge = phi i32 [ -3, %entry ], [ %inc, %loop ]
store i32 %storemerge, ptr @a
%cmp = icmp slt i32 %storemerge, -2
%inc = add nuw nsw i32 %storemerge, 1
br i1 %cmp, label %loop, label %exit
exit:
ret i32 0
}
define i32 @test_no_drop_nsw() {
; CHECK-LABEL: @test_no_drop_nsw(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[STOREMERGE:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[LOOP]] ]
; CHECK-NEXT: store i32 [[STOREMERGE]], ptr @a, align 4
; CHECK-NEXT: [[INC]] = add nuw nsw i32 [[STOREMERGE]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[INC]], 2147483647
; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: ret i32 0
;
entry:
br label %loop
loop:
%storemerge = phi i32 [ 0, %entry ], [ %inc, %loop ]
store i32 %storemerge, ptr @a
%cmp = icmp ult i32 %storemerge, 2147483646
%inc = add nuw nsw i32 %storemerge, 1
br i1 %cmp, label %loop, label %exit
exit:
ret i32 0
}
define i32 @test_no_add_nuw() {
; CHECK-LABEL: @test_no_add_nuw(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[STOREMERGE:%.*]] = phi i32 [ -1, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[LOOP]] ]
; CHECK-NEXT: store i32 [[STOREMERGE]], ptr @a, align 4
; CHECK-NEXT: [[INC]] = add nsw i32 [[STOREMERGE]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[INC]], 10
; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: ret i32 0
;
entry:
br label %loop
loop:
%storemerge = phi i32 [ -1, %entry ], [ %inc, %loop ]
store i32 %storemerge, ptr @a
%cmp = icmp slt i32 %storemerge, 9
%inc = add i32 %storemerge, 1
br i1 %cmp, label %loop, label %exit
exit:
ret i32 0
}
define i32 @test_drop_nsw_var_lim(i32 %lim) {
; CHECK-LABEL: @test_drop_nsw_var_lim(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[LIM:%.*]], -1
; CHECK-NEXT: br i1 [[C]], label [[LOOP_PREHEADER:%.*]], label [[EXIT:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[LIM]], 1
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[STOREMERGE:%.*]] = phi i32 [ [[INC:%.*]], [[LOOP]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: store i32 [[STOREMERGE]], ptr @a, align 4
; CHECK-NEXT: [[INC]] = add nuw i32 [[STOREMERGE]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[INC]], [[TMP0]]
; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT_LOOPEXIT:%.*]]
; CHECK: exit.loopexit:
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 0
;
entry:
%c = icmp ult i32 %lim, -1
br i1 %c, label %loop, label %exit
loop:
%storemerge = phi i32 [ 0, %entry ], [ %inc, %loop ]
store i32 %storemerge, ptr @a
%cmp = icmp ult i32 %storemerge, %lim
%inc = add nuw nsw i32 %storemerge, 1
br i1 %cmp, label %loop, label %exit
exit:
ret i32 0
}
; Adopted from D30446.
; We switch from %iv to %iv2 and need to change nsw to nuw in the process.
define i32 @switch_to_different_iv_post_inc(ptr %ptr, i1 %always_false) {
; CHECK-LABEL: @switch_to_different_iv_post_inc(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[FOR_COND:%.*]]
; CHECK: for.cond:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ -2147483648, [[ENTRY:%.*]] ], [ [[IV_INC:%.*]], [[ALWAYS_TAKEN:%.*]] ]
; CHECK-NEXT: [[IV2:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[IV2_INC:%.*]], [[ALWAYS_TAKEN]] ]
; CHECK-NEXT: store i32 [[IV]], ptr [[PTR:%.*]], align 4
; CHECK-NEXT: br i1 [[ALWAYS_FALSE:%.*]], label [[NEVER_TAKEN:%.*]], label [[ALWAYS_TAKEN]]
; CHECK: never_taken:
; CHECK-NEXT: store volatile i32 [[IV2]], ptr [[PTR]], align 4
; CHECK-NEXT: br label [[ALWAYS_TAKEN]]
; CHECK: always_taken:
; CHECK-NEXT: [[IV_INC]] = add nsw i32 [[IV]], 1
; CHECK-NEXT: [[IV2_INC]] = add nuw i32 [[IV2]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV2_INC]], -2147483627
; CHECK-NEXT: br i1 [[EXITCOND]], label [[FOR_COND]], label [[FOR_END:%.*]]
; CHECK: for.end:
; CHECK-NEXT: ret i32 0
;
entry:
br label %for.cond
for.cond:
%iv = phi i32 [ -2147483648, %entry ], [ %iv.inc, %always_taken ]
%iv2 = phi i32 [ 0, %entry ], [ %iv2.inc, %always_taken ]
store i32 %iv, ptr %ptr
br i1 %always_false, label %never_taken, label %always_taken
never_taken:
store volatile i32 %iv2, ptr %ptr
br label %always_taken
always_taken:
%iv.inc = add nsw i32 %iv, 1
%iv2.inc = add nuw nsw i32 %iv2, 1
%cmp = icmp slt i32 %iv, 20
br i1 %cmp, label %for.cond, label %for.end
for.end:
ret i32 0
}
; Same as previous test case, but with exit block and loop latch being distinct
; blocks requiring the use of pre-increment.
define i32 @switch_to_different_iv_pre_inc(ptr %ptr, i1 %always_false) {
; CHECK-LABEL: @switch_to_different_iv_pre_inc(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[FOR_COND:%.*]]
; CHECK: for.cond:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ -2147483648, [[ENTRY:%.*]] ], [ [[IV_INC:%.*]], [[ALWAYS_TAKEN:%.*]] ]
; CHECK-NEXT: [[IV2:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[IV2_INC:%.*]], [[ALWAYS_TAKEN]] ]
; CHECK-NEXT: store i32 [[IV]], ptr [[PTR:%.*]], align 4
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV2]], -2147483628
; CHECK-NEXT: br i1 [[EXITCOND]], label [[FOR_BODY:%.*]], label [[FOR_END:%.*]]
; CHECK: for.body:
; CHECK-NEXT: br i1 [[ALWAYS_FALSE:%.*]], label [[NEVER_TAKEN:%.*]], label [[ALWAYS_TAKEN]]
; CHECK: never_taken:
; CHECK-NEXT: store volatile i32 [[IV2]], ptr [[PTR]], align 4
; CHECK-NEXT: br label [[ALWAYS_TAKEN]]
; CHECK: always_taken:
; CHECK-NEXT: [[IV_INC]] = add nsw i32 [[IV]], 1
; CHECK-NEXT: [[IV2_INC]] = add nuw i32 [[IV2]], 1
; CHECK-NEXT: br label [[FOR_COND]]
; CHECK: for.end:
; CHECK-NEXT: ret i32 0
;
entry:
br label %for.cond
for.cond:
%iv = phi i32 [ -2147483648, %entry ], [ %iv.inc, %always_taken ]
%iv2 = phi i32 [ 0, %entry ], [ %iv2.inc, %always_taken ]
store i32 %iv, ptr %ptr
%cmp = icmp slt i32 %iv, 20
br i1 %cmp, label %for.body, label %for.end
for.body:
br i1 %always_false, label %never_taken, label %always_taken
never_taken:
store volatile i32 %iv2, ptr %ptr
br label %always_taken
always_taken:
%iv.inc = add nsw i32 %iv, 1
%iv2.inc = add nuw nsw i32 %iv2, 1
br label %for.cond
for.end:
ret i32 0
}
define i32 @switch_to_different_iv_first_poison(ptr %ptr, i1 %always_false) {
; CHECK-LABEL: @switch_to_different_iv_first_poison(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[FOR_COND:%.*]]
; CHECK: for.cond:
; CHECK-NEXT: [[IV2:%.*]] = phi i32 [ -1, [[ENTRY:%.*]] ], [ [[IV2_INC:%.*]], [[ALWAYS_TAKEN:%.*]] ]
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ -2147483648, [[ENTRY]] ], [ [[IV_INC:%.*]], [[ALWAYS_TAKEN]] ]
; CHECK-NEXT: store i32 [[IV]], ptr [[PTR:%.*]], align 4
; CHECK-NEXT: br i1 [[ALWAYS_FALSE:%.*]], label [[NEVER_TAKEN:%.*]], label [[ALWAYS_TAKEN]]
; CHECK: never_taken:
; CHECK-NEXT: store volatile i32 [[IV2]], ptr [[PTR]], align 4
; CHECK-NEXT: br label [[ALWAYS_TAKEN]]
; CHECK: always_taken:
; CHECK-NEXT: [[IV2_INC]] = add nuw nsw i32 [[IV2]], 1
; CHECK-NEXT: [[IV_INC]] = add nsw i32 [[IV]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV2_INC]], -2147483628
; CHECK-NEXT: br i1 [[EXITCOND]], label [[FOR_COND]], label [[FOR_END:%.*]]
; CHECK: for.end:
; CHECK-NEXT: ret i32 0
;
entry:
br label %for.cond
for.cond:
%iv2 = phi i32 [ -1, %entry ], [ %iv2.inc, %always_taken ]
%iv = phi i32 [ -2147483648, %entry ], [ %iv.inc, %always_taken ]
store i32 %iv, ptr %ptr
br i1 %always_false, label %never_taken, label %always_taken
never_taken:
store volatile i32 %iv2, ptr %ptr
br label %always_taken
always_taken:
%iv2.inc = add nuw nsw i32 %iv2, 1
%iv.inc = add nsw i32 %iv, 1
%cmp = icmp slt i32 %iv, 20
br i1 %cmp, label %for.cond, label %for.end
for.end:
ret i32 0
}
define i32 @switch_to_different_iv_second_poison(ptr %ptr, i1 %always_false) {
; CHECK-LABEL: @switch_to_different_iv_second_poison(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[FOR_COND:%.*]]
; CHECK: for.cond:
; CHECK-NEXT: [[IV2:%.*]] = phi i32 [ -2, [[ENTRY:%.*]] ], [ [[IV2_INC:%.*]], [[ALWAYS_TAKEN:%.*]] ]
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ -2147483648, [[ENTRY]] ], [ [[IV_INC:%.*]], [[ALWAYS_TAKEN]] ]
; CHECK-NEXT: store i32 [[IV]], ptr [[PTR:%.*]], align 4
; CHECK-NEXT: br i1 [[ALWAYS_FALSE:%.*]], label [[NEVER_TAKEN:%.*]], label [[ALWAYS_TAKEN]]
; CHECK: never_taken:
; CHECK-NEXT: store volatile i32 [[IV2]], ptr [[PTR]], align 4
; CHECK-NEXT: br label [[ALWAYS_TAKEN]]
; CHECK: always_taken:
; CHECK-NEXT: [[IV2_INC]] = add nsw i32 [[IV2]], 1
; CHECK-NEXT: [[IV_INC]] = add nsw i32 [[IV]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[IV2_INC]], -2147483629
; CHECK-NEXT: br i1 [[EXITCOND]], label [[FOR_COND]], label [[FOR_END:%.*]]
; CHECK: for.end:
; CHECK-NEXT: ret i32 0
;
entry:
br label %for.cond
for.cond:
%iv2 = phi i32 [ -2, %entry ], [ %iv2.inc, %always_taken ]
%iv = phi i32 [ -2147483648, %entry ], [ %iv.inc, %always_taken ]
store i32 %iv, ptr %ptr
br i1 %always_false, label %never_taken, label %always_taken
never_taken:
store volatile i32 %iv2, ptr %ptr
br label %always_taken
always_taken:
%iv2.inc = add nuw nsw i32 %iv2, 1
%iv.inc = add nsw i32 %iv, 1
%cmp = icmp slt i32 %iv, 20
br i1 %cmp, label %for.cond, label %for.end
for.end:
ret i32 0
}