191 lines
4.0 KiB
LLVM
191 lines
4.0 KiB
LLVM
|
; RUN: opt < %s -loop-unroll -S | FileCheck %s
|
||
|
|
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
|
||
|
|
|
||
|
|
; This test shows how unrolling an inner loop could break LCSSA for an outer
|
||
|
|
; loop, and there is no cheap way to recover it.
|
||
|
|
;
|
||
|
|
; In this case the inner loop, L3, is being unrolled. It only runs one
|
||
|
|
; iteration, so unrolling basically means replacing
|
||
|
|
; br i1 true, label %exit, label %L3_header
|
||
|
|
; with
|
||
|
|
; br label %exit
|
||
|
|
;
|
||
|
|
; However, this change messes up the loops structure: for instance, block
|
||
|
|
; L3_body no longer belongs to L2. It becomes an exit block for L2, so LCSSA
|
||
|
|
; phis for definitions in L2 should now be placed there. In particular, we need
|
||
|
|
; to insert such a definition for %y1.
|
||
|
|
|
||
|
|
; CHECK-LABEL: @foo1
|
||
|
|
define void @foo1() {
|
||
|
|
entry:
|
||
|
|
br label %L1_header
|
||
|
|
|
||
|
|
L1_header:
|
||
|
|
br label %L2_header
|
||
|
|
|
||
|
|
L2_header:
|
||
|
|
%y1 = phi i64 [ undef, %L1_header ], [ %x.lcssa, %L2_latch ]
|
||
|
|
br label %L3_header
|
||
|
|
|
||
|
|
L3_header:
|
||
|
|
%y2 = phi i64 [ 0, %L3_latch ], [ %y1, %L2_header ]
|
||
|
|
%x = add i64 undef, -1
|
||
|
|
br i1 true, label %L2_latch, label %L3_body
|
||
|
|
|
||
|
|
L2_latch:
|
||
|
|
%x.lcssa = phi i64 [ %x, %L3_header ]
|
||
|
|
br label %L2_header
|
||
|
|
|
||
|
|
; CHECK: L3_body:
|
||
|
|
; CHECK-NEXT: %y1.lcssa = phi i64 [ %y1, %L3_header ]
|
||
|
|
L3_body:
|
||
|
|
store i64 %y1, i64* undef
|
||
|
|
br i1 false, label %L3_latch, label %L1_latch
|
||
|
|
|
||
|
|
L3_latch:
|
||
|
|
br i1 true, label %exit, label %L3_header
|
||
|
|
|
||
|
|
L1_latch:
|
||
|
|
%y.lcssa = phi i64 [ %y2, %L3_body ]
|
||
|
|
br label %L1_header
|
||
|
|
|
||
|
|
exit:
|
||
|
|
ret void
|
||
|
|
}
|
||
|
|
|
||
|
|
; Additional tests for some corner cases.
|
||
|
|
;
|
||
|
|
; CHECK-LABEL: @foo2
|
||
|
|
define void @foo2() {
|
||
|
|
entry:
|
||
|
|
br label %L1_header
|
||
|
|
|
||
|
|
L1_header:
|
||
|
|
br label %L2_header
|
||
|
|
|
||
|
|
L2_header:
|
||
|
|
%a = phi i64 [ undef, %L1_header ], [ %dec_us, %L3_header ]
|
||
|
|
br label %L3_header
|
||
|
|
|
||
|
|
L3_header:
|
||
|
|
%b = phi i64 [ 0, %L3_latch ], [ %a, %L2_header ]
|
||
|
|
%dec_us = add i64 undef, -1
|
||
|
|
br i1 true, label %L2_header, label %L3_break_to_L1
|
||
|
|
|
||
|
|
; CHECK: L3_break_to_L1:
|
||
|
|
; CHECK-NEXT: %a.lcssa = phi i64 [ %a, %L3_header ]
|
||
|
|
L3_break_to_L1:
|
||
|
|
br i1 false, label %L3_latch, label %L1_latch
|
||
|
|
|
||
|
|
L1_latch:
|
||
|
|
%b_lcssa = phi i64 [ %b, %L3_break_to_L1 ]
|
||
|
|
br label %L1_header
|
||
|
|
|
||
|
|
L3_latch:
|
||
|
|
br i1 true, label %Exit, label %L3_header
|
||
|
|
|
||
|
|
Exit:
|
||
|
|
ret void
|
||
|
|
}
|
||
|
|
|
||
|
|
; CHECK-LABEL: @foo3
|
||
|
|
define void @foo3() {
|
||
|
|
entry:
|
||
|
|
br label %L1_header
|
||
|
|
|
||
|
|
L1_header:
|
||
|
|
%a = phi i8* [ %b, %L1_latch ], [ null, %entry ]
|
||
|
|
br i1 undef, label %L2_header, label %L1_latch
|
||
|
|
|
||
|
|
L2_header:
|
||
|
|
br i1 undef, label %L2_latch, label %L1_latch
|
||
|
|
|
||
|
|
; CHECK: L2_latch:
|
||
|
|
; CHECK-NEXT: %a.lcssa = phi i8* [ %a, %L2_header ]
|
||
|
|
L2_latch:
|
||
|
|
br i1 true, label %L2_exit, label %L2_header
|
||
|
|
|
||
|
|
L1_latch:
|
||
|
|
%b = phi i8* [ undef, %L1_header ], [ null, %L2_header ]
|
||
|
|
br label %L1_header
|
||
|
|
|
||
|
|
L2_exit:
|
||
|
|
%a_lcssa1 = phi i8* [ %a, %L2_latch ]
|
||
|
|
br label %Exit
|
||
|
|
|
||
|
|
Exit:
|
||
|
|
%a_lcssa2 = phi i8* [ %a_lcssa1, %L2_exit ]
|
||
|
|
ret void
|
||
|
|
}
|
||
|
|
|
||
|
|
; PR26688
|
||
|
|
; CHECK-LABEL: @foo4
|
||
|
|
define i8 @foo4() {
|
||
|
|
entry:
|
||
|
|
br label %L1_header
|
||
|
|
|
||
|
|
L1_header:
|
||
|
|
%x = icmp eq i32 1, 0
|
||
|
|
br label %L2_header
|
||
|
|
|
||
|
|
L2_header:
|
||
|
|
br label %L3_header
|
||
|
|
|
||
|
|
L3_header:
|
||
|
|
br i1 true, label %L2_header, label %L3_exiting
|
||
|
|
|
||
|
|
L3_exiting:
|
||
|
|
br i1 true, label %L3_body, label %L1_latch
|
||
|
|
|
||
|
|
; CHECK: L3_body:
|
||
|
|
; CHECK-NEXT: %x.lcssa = phi i1
|
||
|
|
L3_body:
|
||
|
|
br i1 %x, label %L3_latch, label %L3_latch
|
||
|
|
|
||
|
|
L3_latch:
|
||
|
|
br i1 false, label %L3_header, label %exit
|
||
|
|
|
||
|
|
L1_latch:
|
||
|
|
br label %L1_header
|
||
|
|
|
||
|
|
exit:
|
||
|
|
ret i8 0
|
||
|
|
}
|
||
|
|
|
||
|
|
; CHECK-LABEL: @foo5
|
||
|
|
define void @foo5() {
|
||
|
|
entry:
|
||
|
|
br label %outer
|
||
|
|
|
||
|
|
outer:
|
||
|
|
br label %inner1
|
||
|
|
|
||
|
|
; CHECK: inner1:
|
||
|
|
; CHECK-NOT: br i1 true
|
||
|
|
; CHECK: br label %inner2_indirect_exit
|
||
|
|
inner1:
|
||
|
|
br i1 true, label %inner2_indirect_exit.preheader, label %inner1
|
||
|
|
|
||
|
|
inner2_indirect_exit.preheader:
|
||
|
|
br label %inner2_indirect_exit
|
||
|
|
|
||
|
|
inner2_indirect_exit:
|
||
|
|
%a = phi i32 [ %b, %inner2_latch ], [ undef, %inner2_indirect_exit.preheader ]
|
||
|
|
indirectbr i8* undef, [label %inner2_latch, label %inner3, label %outer_latch]
|
||
|
|
|
||
|
|
inner2_latch:
|
||
|
|
%b = load i32, i32* undef, align 8
|
||
|
|
br label %inner2_indirect_exit
|
||
|
|
|
||
|
|
inner3:
|
||
|
|
%a.lcssa = phi i32 [ %a.lcssa, %inner3 ], [ %a, %inner2_indirect_exit ]
|
||
|
|
br i1 true, label %outer_latch.loopexit, label %inner3
|
||
|
|
|
||
|
|
outer_latch.loopexit:
|
||
|
|
%a.lcssa.lcssa = phi i32 [ %a.lcssa, %inner3 ]
|
||
|
|
br label %outer_latch
|
||
|
|
|
||
|
|
outer_latch:
|
||
|
|
br label %outer
|
||
|
|
}
|