llvm-project/llvm/test/Transforms/LICM/preheader-safe.ll

70 lines
1.8 KiB
LLVM

; RUN: opt -S -licm < %s | FileCheck %s
declare void @use_nothrow(i64 %a) nounwind
declare void @use(i64 %a)
define void @nothrow(i64 %x, i64 %y, i1* %cond) {
; CHECK-LABEL: nothrow
; CHECK-LABEL: entry
; CHECK: %div = udiv i64 %x, %y
; CHECK-LABEL: loop
; CHECK: call void @use_nothrow(i64 %div)
entry:
br label %loop
loop: ; preds = %entry, %for.inc
%div = udiv i64 %x, %y
call void @use_nothrow(i64 %div)
br label %loop
}
; Negative test
define void @throw_header(i64 %x, i64 %y, i1* %cond) {
; CHECK-LABEL: throw_header
; CHECK-LABEL: loop
; CHECK: %div = udiv i64 %x, %y
; CHECK: call void @use(i64 %div)
entry:
br label %loop
loop: ; preds = %entry, %for.inc
%div = udiv i64 %x, %y
call void @use(i64 %div)
br label %loop
}
; The header is known no throw, but the loop is not. We can
; still lift out of the header.
define void @nothrow_header(i64 %x, i64 %y, i1 %cond) {
; CHECK-LABEL: nothrow_header
; CHECK-LABEL: entry
; CHECK: %div = udiv i64 %x, %y
; CHECK-LABEL: loop
; CHECK: call void @use(i64 %div)
entry:
br label %loop
loop: ; preds = %entry, %for.inc
%div = udiv i64 %x, %y
br i1 %cond, label %loop-if, label %exit
loop-if:
call void @use(i64 %div)
br label %loop
exit:
ret void
}
; Negative test - can't move out of throwing block
define void @nothrow_header_neg(i64 %x, i64 %y, i1 %cond) {
; CHECK-LABEL: nothrow_header_neg
; CHECK-LABEL: entry
; CHECK-LABEL: loop
; CHECK: %div = udiv i64 %x, %y
; CHECK: call void @use(i64 %div)
entry:
br label %loop
loop: ; preds = %entry, %for.inc
br label %loop-if
loop-if:
%div = udiv i64 %x, %y
call void @use(i64 %div)
br label %loop
}