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| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -simplifycfg -instcombine < %s -simplifycfg-merge-cond-stores=true -simplifycfg-merge-cond-stores-aggressively=false -phi-node-folding-threshold=2 -S | FileCheck %s
; This test should succeed and end up if-converted.
define void @test_simple(i32* %p, i32 %a, i32 %b) {
; CHECK-LABEL: @test_simple(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X1:%.*]] = icmp ne i32 [[A:%.*]], 0
; CHECK-NEXT: [[X2:%.*]] = icmp eq i32 [[B:%.*]], 0
; CHECK-NEXT: [[TMP0:%.*]] = xor i1 [[X2]], true
; CHECK-NEXT: [[TMP1:%.*]] = or i1 [[X1]], [[TMP0]]
; CHECK-NEXT: br i1 [[TMP1]], label [[TMP2:%.*]], label [[TMP3:%.*]]
; CHECK: 2:
; CHECK-NEXT: [[NOT_X2:%.*]] = xor i1 [[X2]], true
; CHECK-NEXT: [[SPEC_SELECT:%.*]] = zext i1 [[NOT_X2]] to i32
; CHECK-NEXT: store i32 [[SPEC_SELECT]], i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[TMP3]]
; CHECK: 3:
; CHECK-NEXT: ret void
;
entry:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %fallthrough, label %yes1
yes1:
store i32 0, i32* %p
br label %fallthrough
fallthrough:
%x2 = icmp eq i32 %b, 0
br i1 %x2, label %end, label %yes2
yes2:
store i32 1, i32* %p
br label %end
end:
ret void
}
; This is the same as test_simple, but the branch target order has been swapped
define void @test_simple_commuted(i32* %p, i32 %a, i32 %b) {
; CHECK-LABEL: @test_simple_commuted(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X1:%.*]] = icmp eq i32 [[A:%.*]], 0
; CHECK-NEXT: [[X2:%.*]] = icmp eq i32 [[B:%.*]], 0
; CHECK-NEXT: [[TMP0:%.*]] = or i1 [[X1]], [[X2]]
; CHECK-NEXT: br i1 [[TMP0]], label [[TMP1:%.*]], label [[TMP2:%.*]]
; CHECK: 1:
; CHECK-NEXT: [[SPEC_SELECT:%.*]] = zext i1 [[X2]] to i32
; CHECK-NEXT: store i32 [[SPEC_SELECT]], i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[TMP2]]
; CHECK: 2:
; CHECK-NEXT: ret void
;
entry:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %yes1, label %fallthrough
yes1:
store i32 0, i32* %p
br label %fallthrough
fallthrough:
%x2 = icmp eq i32 %b, 0
br i1 %x2, label %yes2, label %end
yes2:
store i32 1, i32* %p
br label %end
end:
ret void
}
; This test should entirely fold away, leaving one large basic block.
define void @test_recursive(i32* %p, i32 %a, i32 %b, i32 %c, i32 %d) {
; CHECK-LABEL: @test_recursive(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = or i32 [[B:%.*]], [[A:%.*]]
; CHECK-NEXT: [[X4:%.*]] = icmp eq i32 [[D:%.*]], 0
; CHECK-NEXT: [[TMP1:%.*]] = or i32 [[TMP0]], [[C:%.*]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i32 [[TMP1]], 0
; CHECK-NEXT: [[TMP3:%.*]] = xor i1 [[X4]], true
; CHECK-NEXT: [[TMP4:%.*]] = or i1 [[TMP2]], [[TMP3]]
; CHECK-NEXT: br i1 [[TMP4]], label [[TMP5:%.*]], label [[TMP6:%.*]]
; CHECK: 5:
; CHECK-NEXT: [[X3:%.*]] = icmp eq i32 [[C]], 0
; CHECK-NEXT: [[X2:%.*]] = icmp ne i32 [[B]], 0
; CHECK-NEXT: [[SPEC_SELECT:%.*]] = zext i1 [[X2]] to i32
; CHECK-NEXT: [[SPEC_SELECT1:%.*]] = select i1 [[X3]], i32 [[SPEC_SELECT]], i32 2
; CHECK-NEXT: [[SPEC_SELECT2:%.*]] = select i1 [[X4]], i32 [[SPEC_SELECT1]], i32 3
; CHECK-NEXT: store i32 [[SPEC_SELECT2]], i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[TMP6]]
; CHECK: 6:
; CHECK-NEXT: ret void
;
entry:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %fallthrough, label %yes1
yes1:
store i32 0, i32* %p
br label %fallthrough
fallthrough:
%x2 = icmp eq i32 %b, 0
br i1 %x2, label %next, label %yes2
yes2:
store i32 1, i32* %p
br label %next
next:
%x3 = icmp eq i32 %c, 0
br i1 %x3, label %fallthrough2, label %yes3
yes3:
store i32 2, i32* %p
br label %fallthrough2
fallthrough2:
%x4 = icmp eq i32 %d, 0
br i1 %x4, label %end, label %yes4
yes4:
store i32 3, i32* %p
br label %end
end:
ret void
}
; The code in each diamond is too large - it won't be if-converted so our
; heuristics should say no.
define void @test_not_ifconverted(i32* %p, i32 %a, i32 %b) {
; CHECK-LABEL: @test_not_ifconverted(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X1:%.*]] = icmp eq i32 [[A:%.*]], 0
; CHECK-NEXT: br i1 [[X1]], label [[FALLTHROUGH:%.*]], label [[YES1:%.*]]
; CHECK: yes1:
; CHECK-NEXT: [[Y1:%.*]] = or i32 [[B:%.*]], 55
; CHECK-NEXT: [[Y2:%.*]] = add i32 [[Y1]], 24
; CHECK-NEXT: [[Y3:%.*]] = and i32 [[Y2]], 67
; CHECK-NEXT: store i32 [[Y3]], i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[FALLTHROUGH]]
; CHECK: fallthrough:
; CHECK-NEXT: [[X2:%.*]] = icmp eq i32 [[B]], 0
; CHECK-NEXT: br i1 [[X2]], label [[END:%.*]], label [[YES2:%.*]]
; CHECK: yes2:
; CHECK-NEXT: [[Z1:%.*]] = or i32 [[A]], 55
; CHECK-NEXT: [[Z2:%.*]] = add i32 [[Z1]], 24
; CHECK-NEXT: [[Z3:%.*]] = and i32 [[Z2]], 67
; CHECK-NEXT: store i32 [[Z3]], i32* [[P]], align 4
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: ret void
;
entry:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %fallthrough, label %yes1
yes1:
%y1 = or i32 %b, 55
%y2 = add i32 %y1, 24
%y3 = and i32 %y2, 67
store i32 %y3, i32* %p
br label %fallthrough
fallthrough:
%x2 = icmp eq i32 %b, 0
br i1 %x2, label %end, label %yes2
yes2:
%z1 = or i32 %a, 55
%z2 = add i32 %z1, 24
%z3 = and i32 %z2, 67
store i32 %z3, i32* %p
br label %end
end:
ret void
}
; The store to %p clobbers the previous store, so if-converting this would
; be illegal.
define void @test_aliasing1(i32* %p, i32 %a, i32 %b) {
; CHECK-LABEL: @test_aliasing1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X1:%.*]] = icmp eq i32 [[A:%.*]], 0
; CHECK-NEXT: br i1 [[X1]], label [[FALLTHROUGH:%.*]], label [[YES1:%.*]]
; CHECK: yes1:
; CHECK-NEXT: store i32 0, i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[FALLTHROUGH]]
; CHECK: fallthrough:
; CHECK-NEXT: [[Y1:%.*]] = load i32, i32* [[P]], align 4
; CHECK-NEXT: [[X2:%.*]] = icmp eq i32 [[Y1]], 0
; CHECK-NEXT: br i1 [[X2]], label [[END:%.*]], label [[YES2:%.*]]
; CHECK: yes2:
; CHECK-NEXT: store i32 1, i32* [[P]], align 4
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: ret void
;
entry:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %fallthrough, label %yes1
yes1:
store i32 0, i32* %p
br label %fallthrough
fallthrough:
%y1 = load i32, i32* %p
%x2 = icmp eq i32 %y1, 0
br i1 %x2, label %end, label %yes2
yes2:
store i32 1, i32* %p
br label %end
end:
ret void
}
; The load from %q aliases with %p, so if-converting this would be illegal.
define void @test_aliasing2(i32* %p, i32* %q, i32 %a, i32 %b) {
; CHECK-LABEL: @test_aliasing2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X1:%.*]] = icmp eq i32 [[A:%.*]], 0
; CHECK-NEXT: br i1 [[X1]], label [[FALLTHROUGH:%.*]], label [[YES1:%.*]]
; CHECK: yes1:
; CHECK-NEXT: store i32 0, i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[FALLTHROUGH]]
; CHECK: fallthrough:
; CHECK-NEXT: [[Y1:%.*]] = load i32, i32* [[Q:%.*]], align 4
; CHECK-NEXT: [[X2:%.*]] = icmp eq i32 [[Y1]], 0
; CHECK-NEXT: br i1 [[X2]], label [[END:%.*]], label [[YES2:%.*]]
; CHECK: yes2:
; CHECK-NEXT: store i32 1, i32* [[P]], align 4
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: ret void
;
entry:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %fallthrough, label %yes1
yes1:
store i32 0, i32* %p
br label %fallthrough
fallthrough:
%y1 = load i32, i32* %q
%x2 = icmp eq i32 %y1, 0
br i1 %x2, label %end, label %yes2
yes2:
store i32 1, i32* %p
br label %end
end:
ret void
}
declare void @f()
; This should get if-converted.
define i32 @test_diamond_simple(i32* %p, i32* %q, i32 %a, i32 %b) {
; CHECK-LABEL: @test_diamond_simple(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X1:%.*]] = icmp eq i32 [[A:%.*]], 0
; CHECK-NEXT: [[Z2:%.*]] = select i1 [[X1]], i32 [[B:%.*]], i32 0
; CHECK-NEXT: [[X2:%.*]] = icmp eq i32 [[B]], 0
; CHECK-NEXT: [[Z4:%.*]] = select i1 [[X2]], i32 [[Z2]], i32 3
; CHECK-NEXT: [[TMP0:%.*]] = or i32 [[A]], [[B]]
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[TMP0]], 0
; CHECK-NEXT: br i1 [[TMP1]], label [[TMP3:%.*]], label [[TMP2:%.*]]
; CHECK: 2:
; CHECK-NEXT: [[SIMPLIFYCFG_MERGE:%.*]] = select i1 [[X2]], i32 [[Z2]], i32 1
; CHECK-NEXT: store i32 [[SIMPLIFYCFG_MERGE]], i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[TMP3]]
; CHECK: 3:
; CHECK-NEXT: ret i32 [[Z4]]
;
entry:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %no1, label %yes1
yes1:
store i32 0, i32* %p
br label %fallthrough
no1:
%z1 = add i32 %a, %b
br label %fallthrough
fallthrough:
%z2 = phi i32 [ %z1, %no1 ], [ 0, %yes1 ]
%x2 = icmp eq i32 %b, 0
br i1 %x2, label %no2, label %yes2
yes2:
store i32 1, i32* %p
br label %end
no2:
%z3 = sub i32 %z2, %b
br label %end
end:
%z4 = phi i32 [ %z3, %no2 ], [ 3, %yes2 ]
ret i32 %z4
}
; Now there is a call to f() in the bottom branch. The store in the first
; branch would now be reordered with respect to the call if we if-converted,
; so we must not.
define i32 @test_diamond_alias3(i32* %p, i32* %q, i32 %a, i32 %b) {
; CHECK-LABEL: @test_diamond_alias3(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X1:%.*]] = icmp eq i32 [[A:%.*]], 0
; CHECK-NEXT: br i1 [[X1]], label [[NO1:%.*]], label [[YES1:%.*]]
; CHECK: yes1:
; CHECK-NEXT: store i32 0, i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[FALLTHROUGH:%.*]]
; CHECK: no1:
; CHECK-NEXT: call void @f()
; CHECK-NEXT: [[Z1:%.*]] = add i32 [[A]], [[B:%.*]]
; CHECK-NEXT: br label [[FALLTHROUGH]]
; CHECK: fallthrough:
; CHECK-NEXT: [[Z2:%.*]] = phi i32 [ [[Z1]], [[NO1]] ], [ 0, [[YES1]] ]
; CHECK-NEXT: [[X2:%.*]] = icmp eq i32 [[B]], 0
; CHECK-NEXT: br i1 [[X2]], label [[NO2:%.*]], label [[YES2:%.*]]
; CHECK: yes2:
; CHECK-NEXT: store i32 1, i32* [[P]], align 4
; CHECK-NEXT: br label [[END:%.*]]
; CHECK: no2:
; CHECK-NEXT: call void @f()
; CHECK-NEXT: [[Z3:%.*]] = sub i32 [[Z2]], [[B]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[Z4:%.*]] = phi i32 [ [[Z3]], [[NO2]] ], [ 3, [[YES2]] ]
; CHECK-NEXT: ret i32 [[Z4]]
;
entry:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %no1, label %yes1
yes1:
store i32 0, i32* %p
br label %fallthrough
no1:
call void @f()
%z1 = add i32 %a, %b
br label %fallthrough
fallthrough:
%z2 = phi i32 [ %z1, %no1 ], [ 0, %yes1 ]
%x2 = icmp eq i32 %b, 0
br i1 %x2, label %no2, label %yes2
yes2:
store i32 1, i32* %p
br label %end
no2:
call void @f()
%z3 = sub i32 %z2, %b
br label %end
end:
%z4 = phi i32 [ %z3, %no2 ], [ 3, %yes2 ]
ret i32 %z4
}
; This test has an outer if over the two triangles. This requires creating a new BB to hold the store.
define void @test_outer_if(i32* %p, i32 %a, i32 %b, i32 %c) {
; CHECK-LABEL: @test_outer_if(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[X3:%.*]] = icmp eq i32 [[C:%.*]], 0
; CHECK-NEXT: br i1 [[X3]], label [[END:%.*]], label [[CONTINUE:%.*]]
; CHECK: continue:
; CHECK-NEXT: [[X1:%.*]] = icmp ne i32 [[A:%.*]], 0
; CHECK-NEXT: [[X2:%.*]] = icmp eq i32 [[B:%.*]], 0
; CHECK-NEXT: [[TMP0:%.*]] = xor i1 [[X2]], true
; CHECK-NEXT: [[TMP1:%.*]] = or i1 [[X1]], [[TMP0]]
; CHECK-NEXT: br i1 [[TMP1]], label [[TMP2:%.*]], label [[END]]
; CHECK: 2:
; CHECK-NEXT: [[NOT_X2:%.*]] = xor i1 [[X2]], true
; CHECK-NEXT: [[SPEC_SELECT:%.*]] = zext i1 [[NOT_X2]] to i32
; CHECK-NEXT: store i32 [[SPEC_SELECT]], i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: ret void
;
entry:
%x3 = icmp eq i32 %c, 0
br i1 %x3, label %end, label %continue
continue:
%x1 = icmp eq i32 %a, 0
br i1 %x1, label %fallthrough, label %yes1
yes1:
store i32 0, i32* %p
br label %fallthrough
fallthrough:
%x2 = icmp eq i32 %b, 0
br i1 %x2, label %end, label %yes2
yes2:
store i32 1, i32* %p
br label %end
end:
ret void
}
|