/
loop-predication.ll
838 lines (755 loc) · 37.9 KB
/
loop-predication.ll
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -indvars -indvars-predicate-loops=1 -S | FileCheck %s
declare void @prevent_merging()
; Base case
define i32 @test1(i32* %array, i32 %length, i32 %n) {
; CHECK-LABEL: @test1(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: [[UMAX:%.*]] = call i32 @llvm.umax.i32(i32 [[N:%.*]], i32 1)
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[UMAX]], -1
; CHECK-NEXT: [[UMIN:%.*]] = call i32 @llvm.umin.i32(i32 [[LENGTH:%.*]], i32 [[TMP0]])
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[LENGTH]], [[UMIN]]
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: br i1 [[TMP1]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%within.bounds = icmp ult i32 %i, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64
%array.i = load i32, i32* %array.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc, %array.i
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit: ; preds = %guarded, %entry
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
; Has side effect which must be reflected
define i32 @neg_store(i32* %array, i32 %length, i32 %n) {
; CHECK-LABEL: @neg_store(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[I]], [[LENGTH:%.*]]
; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]]
; CHECK-NEXT: store i32 0, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N:%.*]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%within.bounds = icmp ult i32 %i, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64
%array.i = load i32, i32* %array.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc, %array.i
store i32 0, i32* %array.i.ptr
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit: ; preds = %guarded, %entry
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
declare void @maythrow()
; May exit through implicit exception edge
define i32 @neg_implicit_exit(i32* %array, i32 %length, i32 %n) {
; CHECK-LABEL: @neg_implicit_exit(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: call void @maythrow()
; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[I]], [[LENGTH:%.*]]
; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N:%.*]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ]
call void @maythrow()
%within.bounds = icmp ult i32 %i, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64
%array.i = load i32, i32* %array.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc, %array.i
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit: ; preds = %guarded, %entry
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
; Base case, but in LFTR form (just for sanity checking)
define i32 @test2(i32* %array, i32 %length, i32 %n) {
; CHECK-LABEL: @test2(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[N:%.*]], -1
; CHECK-NEXT: [[UMIN:%.*]] = call i32 @llvm.umin.i32(i32 [[LENGTH:%.*]], i32 [[TMP0]])
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[LENGTH]], [[UMIN]]
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: br i1 [[TMP1]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ne i32 [[I_NEXT]], [[N]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%within.bounds = icmp ne i32 %i, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64
%array.i = load i32, i32* %array.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc, %array.i
%i.next = add nuw i32 %i, 1
%continue = icmp ne i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit: ; preds = %guarded, %entry
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
; br (and rcheck1, rcheck2)
define i32 @two_range_checks(i32* %array.1, i32 %length.1, i32* %array.2, i32 %length.2, i32 %n) {
; CHECK-LABEL: @two_range_checks(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: [[UMIN:%.*]] = call i32 @llvm.umin.i32(i32 [[LENGTH_2:%.*]], i32 [[LENGTH_1:%.*]])
; CHECK-NEXT: [[UMIN1:%.*]] = call i32 @llvm.umin.i32(i32 [[LENGTH_2]], i32 [[LENGTH_1]])
; CHECK-NEXT: [[UMAX:%.*]] = call i32 @llvm.umax.i32(i32 [[N:%.*]], i32 1)
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[UMAX]], -1
; CHECK-NEXT: [[UMIN2:%.*]] = call i32 @llvm.umin.i32(i32 [[UMIN1]], i32 [[TMP0]])
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[UMIN]], [[UMIN2]]
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: br i1 [[TMP1]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_1_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_1:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_1_I:%.*]] = load i32, i32* [[ARRAY_1_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_1:%.*]] = add i32 [[LOOP_ACC]], [[ARRAY_1_I]]
; CHECK-NEXT: [[ARRAY_2_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_2:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_2_I:%.*]] = load i32, i32* [[ARRAY_2_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC_1]], [[ARRAY_2_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%within.bounds.1 = icmp ult i32 %i, %length.1
%within.bounds.2 = icmp ult i32 %i, %length.2
%within.bounds = and i1 %within.bounds.1, %within.bounds.2
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.1.i.ptr = getelementptr inbounds i32, i32* %array.1, i64 %i.i64
%array.1.i = load i32, i32* %array.1.i.ptr, align 4
%loop.acc.1 = add i32 %loop.acc, %array.1.i
%array.2.i.ptr = getelementptr inbounds i32, i32* %array.2, i64 %i.i64
%array.2.i = load i32, i32* %array.2.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc.1, %array.2.i
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit: ; preds = %guarded, %entry
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
define i32 @three_range_checks(i32* %array.1, i32 %length.1, i32* %array.2, i32 %length.2, i32* %array.3, i32 %length.3, i32 %n) {
; CHECK-LABEL: @three_range_checks(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: [[UMIN:%.*]] = call i32 @llvm.umin.i32(i32 [[LENGTH_3:%.*]], i32 [[LENGTH_2:%.*]])
; CHECK-NEXT: [[UMIN1:%.*]] = call i32 @llvm.umin.i32(i32 [[UMIN]], i32 [[LENGTH_1:%.*]])
; CHECK-NEXT: [[UMIN2:%.*]] = call i32 @llvm.umin.i32(i32 [[LENGTH_3]], i32 [[LENGTH_2]])
; CHECK-NEXT: [[UMIN3:%.*]] = call i32 @llvm.umin.i32(i32 [[UMIN2]], i32 [[LENGTH_1]])
; CHECK-NEXT: [[UMAX:%.*]] = call i32 @llvm.umax.i32(i32 [[N:%.*]], i32 1)
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[UMAX]], -1
; CHECK-NEXT: [[UMIN4:%.*]] = call i32 @llvm.umin.i32(i32 [[UMIN3]], i32 [[TMP0]])
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[UMIN1]], [[UMIN4]]
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: br i1 [[TMP1]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_1_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_1:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_1_I:%.*]] = load i32, i32* [[ARRAY_1_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_1:%.*]] = add i32 [[LOOP_ACC]], [[ARRAY_1_I]]
; CHECK-NEXT: [[ARRAY_2_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_2:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_2_I:%.*]] = load i32, i32* [[ARRAY_2_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_2:%.*]] = add i32 [[LOOP_ACC_1]], [[ARRAY_2_I]]
; CHECK-NEXT: [[ARRAY_3_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_3:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_3_I:%.*]] = load i32, i32* [[ARRAY_3_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC_2]], [[ARRAY_3_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%within.bounds.1 = icmp ult i32 %i, %length.1
%within.bounds.2 = icmp ult i32 %i, %length.2
%within.bounds.3 = icmp ult i32 %i, %length.3
%within.bounds.1.and.2 = and i1 %within.bounds.1, %within.bounds.2
%within.bounds = and i1 %within.bounds.1.and.2, %within.bounds.3
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.1.i.ptr = getelementptr inbounds i32, i32* %array.1, i64 %i.i64
%array.1.i = load i32, i32* %array.1.i.ptr, align 4
%loop.acc.1 = add i32 %loop.acc, %array.1.i
%array.2.i.ptr = getelementptr inbounds i32, i32* %array.2, i64 %i.i64
%array.2.i = load i32, i32* %array.2.i.ptr, align 4
%loop.acc.2 = add i32 %loop.acc.1, %array.2.i
%array.3.i.ptr = getelementptr inbounds i32, i32* %array.3, i64 %i.i64
%array.3.i = load i32, i32* %array.3.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc.2, %array.3.i
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit: ; preds = %guarded, %entry
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
; Analogous to the above, but with two distinct branches (on different conditions)
define i32 @distinct_checks(i32* %array.1, i32 %length.1, i32* %array.2, i32 %length.2, i32* %array.3, i32 %length.3, i32 %n) {
; CHECK-LABEL: @distinct_checks(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: [[UMIN:%.*]] = call i32 @llvm.umin.i32(i32 [[LENGTH_2:%.*]], i32 [[LENGTH_1:%.*]])
; CHECK-NEXT: [[UMAX:%.*]] = call i32 @llvm.umax.i32(i32 [[N:%.*]], i32 1)
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[UMAX]], -1
; CHECK-NEXT: [[UMIN1:%.*]] = call i32 @llvm.umin.i32(i32 [[UMIN]], i32 [[TMP0]])
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[LENGTH_1]], [[UMIN1]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i32 [[LENGTH_2]], [[UMIN1]]
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED1:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED1]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: br i1 [[TMP1]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_1_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_1:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_1_I:%.*]] = load i32, i32* [[ARRAY_1_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_1:%.*]] = add i32 [[LOOP_ACC]], [[ARRAY_1_I]]
; CHECK-NEXT: br i1 [[TMP2]], label [[GUARDED1]], label [[DEOPT2:%.*]], !prof !0
; CHECK: deopt2:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded1:
; CHECK-NEXT: [[ARRAY_3_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_3:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_3_I:%.*]] = load i32, i32* [[ARRAY_3_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC_1]], [[ARRAY_3_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED1]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded4, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded1 ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded1 ], [ 0, %loop.preheader ]
%within.bounds.1 = icmp ult i32 %i, %length.1
br i1 %within.bounds.1, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.1.i.ptr = getelementptr inbounds i32, i32* %array.1, i64 %i.i64
%array.1.i = load i32, i32* %array.1.i.ptr, align 4
%loop.acc.1 = add i32 %loop.acc, %array.1.i
%within.bounds.2 = icmp ult i32 %i, %length.2
br i1 %within.bounds.2, label %guarded1, label %deopt2, !prof !0
deopt2: ; preds = %guarded
call void @prevent_merging()
ret i32 -1
guarded1: ; preds = %guarded1
%array.3.i.ptr = getelementptr inbounds i32, i32* %array.3, i64 %i.i64
%array.3.i = load i32, i32* %array.3.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc.1, %array.3.i
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit:
%result = phi i32 [ %loop.acc.next, %guarded1 ]
ret i32 %result
}
define i32 @duplicate_checks(i32* %array.1, i32* %array.2, i32* %array.3, i32 %length, i32 %n) {
; CHECK-LABEL: @duplicate_checks(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: [[UMAX:%.*]] = call i32 @llvm.umax.i32(i32 [[N:%.*]], i32 1)
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[UMAX]], -1
; CHECK-NEXT: [[UMIN:%.*]] = call i32 @llvm.umin.i32(i32 [[LENGTH:%.*]], i32 [[TMP0]])
; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[LENGTH]], [[UMIN]]
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED1:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED1]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: br i1 [[TMP1]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_1_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_1:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_1_I:%.*]] = load i32, i32* [[ARRAY_1_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_1:%.*]] = add i32 [[LOOP_ACC]], [[ARRAY_1_I]]
; CHECK-NEXT: br i1 true, label [[GUARDED1]], label [[DEOPT2:%.*]], !prof !0
; CHECK: deopt2:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded1:
; CHECK-NEXT: [[ARRAY_3_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_3:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_3_I:%.*]] = load i32, i32* [[ARRAY_3_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC_1]], [[ARRAY_3_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED1]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded4, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded1 ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded1 ], [ 0, %loop.preheader ]
%within.bounds.1 = icmp ult i32 %i, %length
br i1 %within.bounds.1, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.1.i.ptr = getelementptr inbounds i32, i32* %array.1, i64 %i.i64
%array.1.i = load i32, i32* %array.1.i.ptr, align 4
%loop.acc.1 = add i32 %loop.acc, %array.1.i
%within.bounds.2 = icmp ult i32 %i, %length
br i1 %within.bounds.2, label %guarded1, label %deopt2, !prof !0
deopt2: ; preds = %guarded
call void @prevent_merging()
ret i32 -1
guarded1: ; preds = %guarded1
%array.3.i.ptr = getelementptr inbounds i32, i32* %array.3, i64 %i.i64
%array.3.i = load i32, i32* %array.3.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc.1, %array.3.i
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit:
%result = phi i32 [ %loop.acc.next, %guarded1 ]
ret i32 %result
}
define i32 @provably_taken(i32* %array, i32* %length.ptr) {
; CHECK-LABEL: @provably_taken(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: br i1 false, label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i32 [[I]], 1
; CHECK-NEXT: br i1 true, label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader:
%length = load i32, i32* %length.ptr, !range !2
br label %loop
loop: ; preds = %guarded, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%within.bounds = icmp ult i32 %i, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64
%array.i = load i32, i32* %array.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc, %array.i
%i.next = add nuw i32 %i, 1
%continue = icmp slt i32 %i.next, 200
br i1 %continue, label %loop, label %exit
exit: ; preds = %guarded
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
; Non-latch exits can still be predicated
define i32 @unconditional_latch(i32* %a, i32 %length) {
; CHECK-LABEL: @unconditional_latch(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: br i1 false, label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: br label [[LOOP]]
;
loop.preheader:
br label %loop
loop: ; preds = %guarded, %loop.preheader
%i = phi i32 [ %i.next, %guarded ], [ 400, %loop.preheader ]
%within.bounds = icmp ult i32 %i, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
%i.next = add i32 %i, 1
br label %loop
}
; Side effect in loop must run proper number of times
define i32 @unconditional_latch_with_side_effect(i32* %a, i32 %length) {
; CHECK-LABEL: @unconditional_latch_with_side_effect(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED:%.*]] ], [ 400, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[I]], [[LENGTH:%.*]]
; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: store volatile i32 0, i32* [[A:%.*]], align 4
; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1
; CHECK-NEXT: br label [[LOOP]]
;
loop.preheader:
br label %loop
loop: ; preds = %guarded, %loop.preheader
%i = phi i32 [ %i.next, %guarded ], [ 400, %loop.preheader ]
%within.bounds = icmp ult i32 %i, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded: ; preds = %loop
store volatile i32 0, i32* %a
%i.next = add i32 %i, 1
br label %loop
}
; Demonstrate that this approach works with IVs of different steps, and types
; This version uses a manually lftred exit condition to work around an issue described
; in detail on next test.
define i32 @different_ivs(i32* %array, i32 %length, i32 %n) {
; CHECK-LABEL: @different_ivs(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: [[N64:%.*]] = zext i32 [[N:%.*]] to i64
; CHECK-NEXT: [[UMAX:%.*]] = call i64 @llvm.umax.i64(i64 [[N64]], i64 1)
; CHECK-NEXT: [[TMP0:%.*]] = add nsw i64 [[UMAX]], -1
; CHECK-NEXT: [[TMP1:%.*]] = zext i32 [[LENGTH:%.*]] to i64
; CHECK-NEXT: [[UMIN:%.*]] = call i64 @llvm.umin.i64(i64 [[TMP0]], i64 [[TMP1]])
; CHECK-NEXT: [[TMP2:%.*]] = zext i32 [[LENGTH]] to i64
; CHECK-NEXT: [[TMP3:%.*]] = icmp ne i64 [[TMP2]], [[UMIN]]
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i64 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: br i1 [[TMP3]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I]]
; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i64 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i64 [[I_NEXT]], [[N64]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
loop.preheader:
%j.start = sub nuw nsw i32 %length, 1
%n64 = zext i32 %n to i64
br label %loop
loop:
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i64 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%j = phi i32 [ %j.next, %guarded ], [ %j.start, %loop.preheader ]
%within.bounds = icmp ne i32 %j, -1
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt:
call void @prevent_merging()
ret i32 -1
guarded:
%array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i
%array.i = load i32, i32* %array.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc, %array.i
%i.next = add nuw i64 %i, 1
%j.next = sub nuw i32 %j, 1
%continue = icmp ult i64 %i.next, %n64
br i1 %continue, label %loop, label %exit
exit:
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
; TODO: We're failing to compute an exit count for the bounds check.
; From some quick analysis, it looks like we don't handle -1 step
; in howManyLessThans. Should be a simple fix.
define i32 @different_ivs2(i32* %array, i32 %length, i32 %n) {
; CHECK-LABEL: @different_ivs2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[POS_LENGTH:%.*]] = icmp sgt i32 [[LENGTH:%.*]], 0
; CHECK-NEXT: br i1 [[POS_LENGTH]], label [[LOOP_PREHEADER:%.*]], label [[EXIT:%.*]]
; CHECK: loop.preheader:
; CHECK-NEXT: [[J_START:%.*]] = sub nuw nsw i32 [[LENGTH]], 1
; CHECK-NEXT: [[N64:%.*]] = zext i32 [[N:%.*]] to i64
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[I:%.*]] = phi i64 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[J:%.*]] = phi i32 [ [[J_NEXT:%.*]], [[GUARDED]] ], [ [[J_START]], [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[J]], [[LENGTH]]
; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded:
; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I]]
; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i64 [[I]], 1
; CHECK-NEXT: [[J_NEXT]] = sub nuw i32 [[J]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i64 [[I_NEXT]], [[N64]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT_LOOPEXIT:%.*]]
; CHECK: exit.loopexit:
; CHECK-NEXT: [[LOOP_ACC_NEXT_LCSSA:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ]
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_ACC_NEXT_LCSSA]], [[EXIT_LOOPEXIT]] ]
; CHECK-NEXT: ret i32 [[RESULT]]
;
entry:
%pos_length = icmp sgt i32 %length, 0
br i1 %pos_length, label %loop.preheader, label %exit
loop.preheader:
%j.start = sub nuw nsw i32 %length, 1
%n64 = zext i32 %n to i64
br label %loop
loop:
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i64 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%j = phi i32 [ %j.next, %guarded ], [ %j.start, %loop.preheader ]
%within.bounds = icmp ult i32 %j, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt:
call void @prevent_merging()
ret i32 -1
guarded:
%array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i
%array.i = load i32, i32* %array.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc, %array.i
%i.next = add nuw i64 %i, 1
%j.next = sub nuw i32 %j, 1
%continue = icmp ult i64 %i.next, %n64
br i1 %continue, label %loop, label %exit
exit:
%result = phi i32 [ %loop.acc.next, %guarded ], [0, %entry]
ret i32 %result
}
; If we have a dominating exit (exit1) which can't be itself rewritten, we
; can't rewrite a later exit (exit2). Doing so would cause the loop to exit
; from the exit2 when it should have exited from exit1.
define i32 @neg_dominating_exit(i32* %array, i32 %length, i32 %length2, i32 %n) {
; CHECK-LABEL: @neg_dominating_exit(
; CHECK-NEXT: loop.preheader:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED2:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ]
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED2]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[I]], [[LENGTH:%.*]]
; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC]], [[LOOP]] ]
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 [[RESULT]]
; CHECK: guarded:
; CHECK-NEXT: [[WITHIN_BOUNDS2:%.*]] = icmp ult i32 [[I]], [[LENGTH2:%.*]]
; CHECK-NEXT: br i1 [[WITHIN_BOUNDS2]], label [[GUARDED2]], label [[DEOPT2:%.*]], !prof !0
; CHECK: deopt2:
; CHECK-NEXT: call void @prevent_merging()
; CHECK-NEXT: ret i32 -1
; CHECK: guarded2:
; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]]
; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4
; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]]
; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1
; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N:%.*]]
; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[RESULT2:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED2]] ]
; CHECK-NEXT: ret i32 [[RESULT2]]
;
loop.preheader: ; preds = %entry
br label %loop
loop: ; preds = %guarded, %loop.preheader
%loop.acc = phi i32 [ %loop.acc.next, %guarded2 ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded2 ], [ 0, %loop.preheader ]
%within.bounds = icmp ult i32 %i, %length
br i1 %within.bounds, label %guarded, label %deopt, !prof !0
deopt: ; preds = %loop
%result = phi i32 [ %loop.acc, %loop ]
call void @prevent_merging()
ret i32 %result
guarded: ; preds = %loop
%within.bounds2 = icmp ult i32 %i, %length2
br i1 %within.bounds2, label %guarded2, label %deopt2, !prof !0
deopt2: ; preds = %loop
call void @prevent_merging()
ret i32 -1
guarded2: ; preds = %loop
%i.i64 = zext i32 %i to i64
%array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64
%array.i = load i32, i32* %array.i.ptr, align 4
%loop.acc.next = add i32 %loop.acc, %array.i
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit: ; preds = %guarded, %entry
%result2 = phi i32 [ %loop.acc.next, %guarded2 ]
ret i32 %result2
}
declare i32 @llvm.experimental.deoptimize.i32(...)
!0 = !{!"branch_weights", i32 1048576, i32 1}
!1 = !{i32 1, i32 -2147483648}
!2 = !{i32 0, i32 50}