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; RUN: opt -S -loop-unswitch < %s | FileCheck %s
; RUN: opt -S -loop-unswitch -enable-mssa-loop-dependency=true -verify-memoryssa < %s | FileCheck %s
declare void @llvm.experimental.guard(i1, ...)
define void @f_0(i32 %n, i32* %ptr, i1 %c) {
; CHECK-LABEL: @f_0(
; CHECK: loop.us:
; CHECK-NOT: guard
; CHECK: loop:
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 false) [ "deopt"() ]
entry:
br label %loop
loop:
%iv = phi i32 [ 0, %entry ], [ %iv.inc, %loop ]
%iv.inc = add i32 %iv, 1
call void(i1, ...) @llvm.experimental.guard(i1 %c) [ "deopt"() ]
store volatile i32 0, i32* %ptr
%becond = icmp ult i32 %iv.inc, %n
br i1 %becond, label %leave, label %loop
leave:
ret void
}
define void @f_1(i32 %n, i32* %ptr, i1 %c_0, i1 %c_1) {
; CHECK-LABEL: @f_1(
; CHECK: loop.us.us:
; CHECK-NOT: guard
; CHECK: loop.us:
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 false) [ "deopt"(i32 2) ]
; CHECK-NOT: guard
; CHECK: loop.us1:
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 false) [ "deopt"(i32 1) ]
; CHECK-NOT: guard
; CHECK: loop:
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 false) [ "deopt"(i32 1) ]
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 false) [ "deopt"(i32 2) ]
entry:
br label %loop
loop:
%iv = phi i32 [ 0, %entry ], [ %iv.inc, %loop ]
%iv.inc = add i32 %iv, 1
call void(i1, ...) @llvm.experimental.guard(i1 %c_0) [ "deopt"(i32 1) ]
store volatile i32 0, i32* %ptr
call void(i1, ...) @llvm.experimental.guard(i1 %c_1) [ "deopt"(i32 2) ]
%becond = icmp ult i32 %iv.inc, %n
br i1 %becond, label %leave, label %loop
leave:
ret void
}
; Basic negative test
define void @f_3(i32 %n, i32* %ptr, i1* %c_ptr) {
; CHECK-LABEL: @f_3(
; CHECK-NOT: loop.us:
entry:
br label %loop
loop:
%iv = phi i32 [ 0, %entry ], [ %iv.inc, %loop ]
%iv.inc = add i32 %iv, 1
%c = load volatile i1, i1* %c_ptr
call void(i1, ...) @llvm.experimental.guard(i1 %c) [ "deopt"() ]
store volatile i32 0, i32* %ptr
%becond = icmp ult i32 %iv.inc, %n
br i1 %becond, label %leave, label %loop
leave:
ret void
}
define void @f_4(i32 %n, i32* %ptr, i1 %c) {
; CHECK-LABEL: @f_4(
;
; Demonstrate that unswitching on one guard can cause another guard to
; be erased (this has implications on what guards we can keep raw
; pointers to).
entry:
br label %loop
loop:
%iv = phi i32 [ 0, %entry ], [ %iv.inc, %loop ]
%iv.inc = add i32 %iv, 1
call void(i1, ...) @llvm.experimental.guard(i1 %c) [ "deopt"(i32 1) ]
store volatile i32 0, i32* %ptr
%neg = xor i1 %c, 1
call void(i1, ...) @llvm.experimental.guard(i1 %neg) [ "deopt"(i32 2) ]
%becond = icmp ult i32 %iv.inc, %n
br i1 %becond, label %leave, label %loop
leave:
ret void
}
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