; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
; RUN: opt < %s -passes=correlated-propagation -S | FileCheck %s
define void @test1(i32 %n) {
; CHECK-LABEL: define void @test1(
; CHECK-SAME: i32 [[N:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_COND:.*]]
; CHECK: [[FOR_COND]]:
; CHECK-NEXT: [[A:%.*]] = phi i32 [ [[N]], %[[ENTRY]] ], [ [[SHR:%.*]], %[[FOR_BODY:.*]] ]
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[A]], 1
; CHECK-NEXT: br i1 [[CMP]], label %[[FOR_BODY]], label %[[FOR_END:.*]]
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[SHR]] = lshr i32 [[A]], 5
; CHECK-NEXT: br label %[[FOR_COND]]
; CHECK: [[FOR_END]]:
; CHECK-NEXT: ret void
;
entry:
br label %for.cond
for.cond: ; preds = %for.body, %entry
%a = phi i32 [ %n, %entry ], [ %shr, %for.body ]
%cmp = icmp sgt i32 %a, 1
br i1 %cmp, label %for.body, label %for.end
for.body: ; preds = %for.cond
%shr = ashr i32 %a, 5
br label %for.cond
for.end: ; preds = %for.cond
ret void
}
;; Negative test to show transform doesn't happen unless n > 0.
define void @test2(i32 %n) {
; CHECK-LABEL: define void @test2(
; CHECK-SAME: i32 [[N:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_COND:.*]]
; CHECK: [[FOR_COND]]:
; CHECK-NEXT: [[A:%.*]] = phi i32 [ [[N]], %[[ENTRY]] ], [ [[SHR:%.*]], %[[FOR_BODY:.*]] ]
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[A]], -2
; CHECK-NEXT: br i1 [[CMP]], label %[[FOR_BODY]], label %[[FOR_END:.*]]
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[SHR]] = ashr i32 [[A]], 2
; CHECK-NEXT: br label %[[FOR_COND]]
; CHECK: [[FOR_END]]:
; CHECK-NEXT: ret void
;
entry:
br label %for.cond
for.cond: ; preds = %for.body, %entry
%a = phi i32 [ %n, %entry ], [ %shr, %for.body ]
%cmp = icmp sgt i32 %a, -2
br i1 %cmp, label %for.body, label %for.end
for.body: ; preds = %for.cond
%shr = ashr i32 %a, 2
br label %for.cond
for.end: ; preds = %for.cond
ret void
}
;; Non looping test case.
define void @test3(i32 %n) {
; CHECK-LABEL: define void @test3(
; CHECK-SAME: i32 [[N:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[N]], 0
; CHECK-NEXT: br i1 [[CMP]], label %[[BB:.*]], label %[[EXIT:.*]]
; CHECK: [[BB]]:
; CHECK-NEXT: [[SHR:%.*]] = lshr exact i32 [[N]], 4
; CHECK-NEXT: br label %[[EXIT]]
; CHECK: [[EXIT]]:
; CHECK-NEXT: ret void
;
entry:
%cmp = icmp sgt i32 %n, 0
br i1 %cmp, label %bb, label %exit
bb:
%shr = ashr exact i32 %n, 4
br label %exit
exit:
ret void
}
; looping case where loop has exactly one block
; at the point of ashr, we know that the operand is always greater than 0,
; because of the guard before it, so we can transform it to lshr.
declare void @llvm.experimental.guard(i1,...)
define void @test4(i32 %n) {
; CHECK-LABEL: define void @test4(
; CHECK-SAME: i32 [[N:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[N]], 0
; CHECK-NEXT: br i1 [[CMP]], label %[[LOOP:.*]], label %[[EXIT:.*]]
; CHECK: [[LOOP]]:
; CHECK-NEXT: [[A:%.*]] = phi i32 [ [[N]], %[[ENTRY]] ], [ [[SHR:%.*]], %[[LOOP]] ]
; CHECK-NEXT: [[COND:%.*]] = icmp sgt i32 [[A]], 2
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 [[COND]]) [ "deopt"() ]
; CHECK-NEXT: [[SHR]] = lshr i32 [[A]], 1
; CHECK-NEXT: br i1 [[COND]], label %[[LOOP]], label %[[EXIT]]
; CHECK: [[EXIT]]:
; CHECK-NEXT: ret void
;
entry:
%cmp = icmp sgt i32 %n, 0
br i1 %cmp, label %loop, label %exit
loop:
%a = phi i32 [ %n, %entry ], [ %shr, %loop ]
%cond = icmp sgt i32 %a, 2
call void(i1,...) @llvm.experimental.guard(i1 %cond) [ "deopt"() ]
%shr = ashr i32 %a, 1
br i1 %cond, label %loop, label %exit
exit:
ret void
}
; same test as above with assume instead of guard.
declare void @llvm.assume(i1)
define void @test5(i32 %n) {
; CHECK-LABEL: define void @test5(
; CHECK-SAME: i32 [[N:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[N]], 0
; CHECK-NEXT: br i1 [[CMP]], label %[[LOOP:.*]], label %[[EXIT:.*]]
; CHECK: [[LOOP]]:
; CHECK-NEXT: [[A:%.*]] = phi i32 [ [[N]], %[[ENTRY]] ], [ [[SHR:%.*]], %[[LOOP]] ]
; CHECK-NEXT: [[COND:%.*]] = icmp ugt i32 [[A]], 4
; CHECK-NEXT: call void @llvm.assume(i1 [[COND]])
; CHECK-NEXT: [[SHR]] = lshr i32 [[A]], 1
; CHECK-NEXT: [[LOOPCOND:%.*]] = icmp ugt i32 [[SHR]], 8
; CHECK-NEXT: br i1 [[LOOPCOND]], label %[[LOOP]], label %[[EXIT]]
; CHECK: [[EXIT]]:
; CHECK-NEXT: ret void
;
entry:
%cmp = icmp sgt i32 %n, 0
br i1 %cmp, label %loop, label %exit
loop:
%a = phi i32 [ %n, %entry ], [ %shr, %loop ]
%cond = icmp sgt i32 %a, 4
call void @llvm.assume(i1 %cond)
%shr = ashr i32 %a, 1
%loopcond = icmp sgt i32 %shr, 8
br i1 %loopcond, label %loop, label %exit
exit:
ret void
}
; check that ashr of -1 or 0 is optimized away
define i32 @test6(i32 %f, i32 %g) {
; CHECK-LABEL: define i32 @test6(
; CHECK-SAME: i32 [[F:%.*]], i32 [[G:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[F]], 1
; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[TMP0]], 2
; CHECK-NEXT: tail call void @llvm.assume(i1 [[TMP1]])
; CHECK-NEXT: ret i32 [[F]]
;
entry:
%0 = add i32 %f, 1
%1 = icmp ult i32 %0, 2
tail call void @llvm.assume(i1 %1)
%shr = ashr i32 %f, %g
ret i32 %shr
}
; same test as above with different numbers
define i32 @test7(i32 %f, i32 %g) {
; CHECK-LABEL: define i32 @test7(
; CHECK-SAME: i32 [[F:%.*]], i32 [[G:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; CHECK-NEXT: [[TMP0:%.*]] = and i32 [[F]], -2
; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i32 [[TMP0]], 6
; CHECK-NEXT: tail call void @llvm.assume(i1 [[TMP1]])
; CHECK-NEXT: [[SUB:%.*]] = add nsw i32 [[F]], -7
; CHECK-NEXT: ret i32 [[SUB]]
;
entry:
%0 = and i32 %f, -2
%1 = icmp eq i32 %0, 6
tail call void @llvm.assume(i1 %1)
%sub = add nsw i32 %f, -7
%shr = ashr i32 %sub, %g
ret i32 %shr
}
; check that ashr of -2 or 1 is not optimized away
define i32 @test8(i32 %f, i32 %g, i1 %s) {
; CHECK-LABEL: define i32 @test8(
; CHECK-SAME: i32 [[F:%.*]], i32 [[G:%.*]], i1 [[S:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*:]]
; CHECK-NEXT: [[TMP0:%.*]] = ashr i32 -2, [[F]]
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 1, [[G]]
; CHECK-NEXT: [[TMP2:%.*]] = select i1 [[S]], i32 [[TMP0]], i32 [[TMP1]]
; CHECK-NEXT: ret i32 [[TMP2]]
;
entry:
%0 = ashr i32 -2, %f
%1 = ashr i32 1, %g
%2 = select i1 %s, i32 %0, i32 %1
ret i32 %2
}
define i32 @may_including_undef(i1 %c.1, i1 %c.2) {
; CHECK-LABEL: define i32 @may_including_undef(
; CHECK-SAME: i1 [[C_1:%.*]], i1 [[C_2:%.*]]) {
; CHECK-NEXT: br i1 [[C_1]], label %[[TRUE_1:.*]], label %[[FALSE:.*]]
; CHECK: [[TRUE_1]]:
; CHECK-NEXT: br i1 [[C_2]], label %[[TRUE_2:.*]], label %[[EXIT:.*]]
; CHECK: [[TRUE_2]]:
; CHECK-NEXT: br label %[[EXIT]]
; CHECK: [[FALSE]]:
; CHECK-NEXT: br label %[[EXIT]]
; CHECK: [[EXIT]]:
; CHECK-NEXT: [[P:%.*]] = phi i32 [ 2, %[[TRUE_1]] ], [ 4, %[[TRUE_2]] ], [ undef, %[[FALSE]] ]
; CHECK-NEXT: [[R:%.*]] = ashr i32 [[P]], 1
; CHECK-NEXT: ret i32 [[R]]
;
br i1 %c.1, label %true.1, label %false
true.1:
br i1 %c.2, label %true.2, label %exit
true.2:
br label %exit
false:
br label %exit
exit:
%p = phi i32 [ 2, %true.1 ], [ 4, %true.2], [ undef, %false ]
%r = ashr i32 %p, 1
ret i32 %r
}
Codebase Browser
llvm