mirror of
https://github.com/RPCS3/llvm.git
synced 2025-02-13 23:00:33 +00:00
3273c8937b
block sequence when recovering from unanalyzable control flow constructs, *always* use the function sequence. I'm not sure why I ever went down the path of trying to use the loop sequence, it is fundamentally not the correct sequence to use. We're trying to preserve the incoming layout in the cases of unreasonable control flow, and that is only encoded at the function level. We already have a filter to select *exactly* the sub-set of blocks within the function that we're trying to form into a chain. The resulting code layout is also significantly better because of this. In several places we were ending up with completely unreasonable control flow constructs due to the ordering chosen by the loop structure for its internal storage. This change removes a completely wasteful vector of basic blocks, saving memory allocation in the common case even though it costs us CPU in the fairly rare case of unnatural loops. Finally, it fixes the latest crasher reduced out of GCC's single source. Thanks again to Benjamin Kramer for the reduction, my bugpoint skills failed at it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144627 91177308-0d34-0410-b5e6-96231b3b80d8
396 lines
9.2 KiB
LLVM
396 lines
9.2 KiB
LLVM
; RUN: llc -march=x86 -enable-block-placement < %s | FileCheck %s
|
|
|
|
declare void @error(i32 %i, i32 %a, i32 %b)
|
|
|
|
define i32 @test_ifchains(i32 %i, i32* %a, i32 %b) {
|
|
; Test a chain of ifs, where the block guarded by the if is error handling code
|
|
; that is not expected to run.
|
|
; CHECK: test_ifchains:
|
|
; CHECK: %entry
|
|
; CHECK: %else1
|
|
; CHECK: %else2
|
|
; CHECK: %else3
|
|
; CHECK: %else4
|
|
; CHECK: %exit
|
|
; CHECK: %then1
|
|
; CHECK: %then2
|
|
; CHECK: %then3
|
|
; CHECK: %then4
|
|
; CHECK: %then5
|
|
|
|
entry:
|
|
%gep1 = getelementptr i32* %a, i32 1
|
|
%val1 = load i32* %gep1
|
|
%cond1 = icmp ugt i32 %val1, 1
|
|
br i1 %cond1, label %then1, label %else1, !prof !0
|
|
|
|
then1:
|
|
call void @error(i32 %i, i32 1, i32 %b)
|
|
br label %else1
|
|
|
|
else1:
|
|
%gep2 = getelementptr i32* %a, i32 2
|
|
%val2 = load i32* %gep2
|
|
%cond2 = icmp ugt i32 %val2, 2
|
|
br i1 %cond2, label %then2, label %else2, !prof !0
|
|
|
|
then2:
|
|
call void @error(i32 %i, i32 1, i32 %b)
|
|
br label %else2
|
|
|
|
else2:
|
|
%gep3 = getelementptr i32* %a, i32 3
|
|
%val3 = load i32* %gep3
|
|
%cond3 = icmp ugt i32 %val3, 3
|
|
br i1 %cond3, label %then3, label %else3, !prof !0
|
|
|
|
then3:
|
|
call void @error(i32 %i, i32 1, i32 %b)
|
|
br label %else3
|
|
|
|
else3:
|
|
%gep4 = getelementptr i32* %a, i32 4
|
|
%val4 = load i32* %gep4
|
|
%cond4 = icmp ugt i32 %val4, 4
|
|
br i1 %cond4, label %then4, label %else4, !prof !0
|
|
|
|
then4:
|
|
call void @error(i32 %i, i32 1, i32 %b)
|
|
br label %else4
|
|
|
|
else4:
|
|
%gep5 = getelementptr i32* %a, i32 3
|
|
%val5 = load i32* %gep5
|
|
%cond5 = icmp ugt i32 %val5, 3
|
|
br i1 %cond5, label %then5, label %exit, !prof !0
|
|
|
|
then5:
|
|
call void @error(i32 %i, i32 1, i32 %b)
|
|
br label %exit
|
|
|
|
exit:
|
|
ret i32 %b
|
|
}
|
|
|
|
define i32 @test_loop_cold_blocks(i32 %i, i32* %a) {
|
|
; Check that we sink cold loop blocks after the hot loop body.
|
|
; CHECK: test_loop_cold_blocks:
|
|
; CHECK: %entry
|
|
; CHECK: %body1
|
|
; CHECK: %body2
|
|
; CHECK: %body3
|
|
; CHECK: %unlikely1
|
|
; CHECK: %unlikely2
|
|
; CHECK: %exit
|
|
|
|
entry:
|
|
br label %body1
|
|
|
|
body1:
|
|
%iv = phi i32 [ 0, %entry ], [ %next, %body3 ]
|
|
%base = phi i32 [ 0, %entry ], [ %sum, %body3 ]
|
|
%unlikelycond1 = icmp slt i32 %base, 42
|
|
br i1 %unlikelycond1, label %unlikely1, label %body2, !prof !0
|
|
|
|
unlikely1:
|
|
call void @error(i32 %i, i32 1, i32 %base)
|
|
br label %body2
|
|
|
|
body2:
|
|
%unlikelycond2 = icmp sgt i32 %base, 21
|
|
br i1 %unlikelycond2, label %unlikely2, label %body3, !prof !0
|
|
|
|
unlikely2:
|
|
call void @error(i32 %i, i32 2, i32 %base)
|
|
br label %body3
|
|
|
|
body3:
|
|
%arrayidx = getelementptr inbounds i32* %a, i32 %iv
|
|
%0 = load i32* %arrayidx
|
|
%sum = add nsw i32 %0, %base
|
|
%next = add i32 %iv, 1
|
|
%exitcond = icmp eq i32 %next, %i
|
|
br i1 %exitcond, label %exit, label %body1
|
|
|
|
exit:
|
|
ret i32 %sum
|
|
}
|
|
|
|
!0 = metadata !{metadata !"branch_weights", i32 4, i32 64}
|
|
|
|
define i32 @test_loop_early_exits(i32 %i, i32* %a) {
|
|
; Check that we sink early exit blocks out of loop bodies.
|
|
; CHECK: test_loop_early_exits:
|
|
; CHECK: %entry
|
|
; CHECK: %body1
|
|
; CHECK: %body2
|
|
; CHECK: %body3
|
|
; CHECK: %body4
|
|
; CHECK: %exit
|
|
; CHECK: %bail1
|
|
; CHECK: %bail2
|
|
; CHECK: %bail3
|
|
|
|
entry:
|
|
br label %body1
|
|
|
|
body1:
|
|
%iv = phi i32 [ 0, %entry ], [ %next, %body4 ]
|
|
%base = phi i32 [ 0, %entry ], [ %sum, %body4 ]
|
|
%bailcond1 = icmp eq i32 %base, 42
|
|
br i1 %bailcond1, label %bail1, label %body2
|
|
|
|
bail1:
|
|
ret i32 -1
|
|
|
|
body2:
|
|
%bailcond2 = icmp eq i32 %base, 43
|
|
br i1 %bailcond2, label %bail2, label %body3
|
|
|
|
bail2:
|
|
ret i32 -2
|
|
|
|
body3:
|
|
%bailcond3 = icmp eq i32 %base, 44
|
|
br i1 %bailcond3, label %bail3, label %body4
|
|
|
|
bail3:
|
|
ret i32 -3
|
|
|
|
body4:
|
|
%arrayidx = getelementptr inbounds i32* %a, i32 %iv
|
|
%0 = load i32* %arrayidx
|
|
%sum = add nsw i32 %0, %base
|
|
%next = add i32 %iv, 1
|
|
%exitcond = icmp eq i32 %next, %i
|
|
br i1 %exitcond, label %exit, label %body1
|
|
|
|
exit:
|
|
ret i32 %sum
|
|
}
|
|
|
|
define i32 @test_loop_align(i32 %i, i32* %a) {
|
|
; Check that we provide basic loop body alignment with the block placement
|
|
; pass.
|
|
; CHECK: test_loop_align:
|
|
; CHECK: %entry
|
|
; CHECK: .align [[ALIGN:[0-9]+]],
|
|
; CHECK-NEXT: %body
|
|
; CHECK: %exit
|
|
|
|
entry:
|
|
br label %body
|
|
|
|
body:
|
|
%iv = phi i32 [ 0, %entry ], [ %next, %body ]
|
|
%base = phi i32 [ 0, %entry ], [ %sum, %body ]
|
|
%arrayidx = getelementptr inbounds i32* %a, i32 %iv
|
|
%0 = load i32* %arrayidx
|
|
%sum = add nsw i32 %0, %base
|
|
%next = add i32 %iv, 1
|
|
%exitcond = icmp eq i32 %next, %i
|
|
br i1 %exitcond, label %exit, label %body
|
|
|
|
exit:
|
|
ret i32 %sum
|
|
}
|
|
|
|
define i32 @test_nested_loop_align(i32 %i, i32* %a, i32* %b) {
|
|
; Check that we provide nested loop body alignment.
|
|
; CHECK: test_nested_loop_align:
|
|
; CHECK: %entry
|
|
; CHECK: .align [[ALIGN]],
|
|
; CHECK-NEXT: %loop.body.1
|
|
; CHECK: .align [[ALIGN]],
|
|
; CHECK-NEXT: %inner.loop.body
|
|
; CHECK-NOT: .align
|
|
; CHECK: %exit
|
|
|
|
entry:
|
|
br label %loop.body.1
|
|
|
|
loop.body.1:
|
|
%iv = phi i32 [ 0, %entry ], [ %next, %loop.body.2 ]
|
|
%arrayidx = getelementptr inbounds i32* %a, i32 %iv
|
|
%bidx = load i32* %arrayidx
|
|
br label %inner.loop.body
|
|
|
|
inner.loop.body:
|
|
%inner.iv = phi i32 [ 0, %loop.body.1 ], [ %inner.next, %inner.loop.body ]
|
|
%base = phi i32 [ 0, %loop.body.1 ], [ %sum, %inner.loop.body ]
|
|
%scaled_idx = mul i32 %bidx, %iv
|
|
%inner.arrayidx = getelementptr inbounds i32* %b, i32 %scaled_idx
|
|
%0 = load i32* %inner.arrayidx
|
|
%sum = add nsw i32 %0, %base
|
|
%inner.next = add i32 %iv, 1
|
|
%inner.exitcond = icmp eq i32 %inner.next, %i
|
|
br i1 %inner.exitcond, label %loop.body.2, label %inner.loop.body
|
|
|
|
loop.body.2:
|
|
%next = add i32 %iv, 1
|
|
%exitcond = icmp eq i32 %next, %i
|
|
br i1 %exitcond, label %exit, label %loop.body.1
|
|
|
|
exit:
|
|
ret i32 %sum
|
|
}
|
|
|
|
define void @unnatural_cfg1() {
|
|
; Test that we can handle a loop with an inner unnatural loop at the end of
|
|
; a function. This is a gross CFG reduced out of the single source GCC.
|
|
; CHECK: unnatural_cfg1
|
|
; CHECK: %entry
|
|
; CHECK: %loop.body1
|
|
; CHECK: %loop.body2
|
|
; CHECK: %loop.body3
|
|
|
|
entry:
|
|
br label %loop.header
|
|
|
|
loop.header:
|
|
br label %loop.body1
|
|
|
|
loop.body1:
|
|
br i1 undef, label %loop.body3, label %loop.body2
|
|
|
|
loop.body2:
|
|
%ptr = load i32** undef, align 4
|
|
br label %loop.body3
|
|
|
|
loop.body3:
|
|
%myptr = phi i32* [ %ptr2, %loop.body5 ], [ %ptr, %loop.body2 ], [ undef, %loop.body1 ]
|
|
%bcmyptr = bitcast i32* %myptr to i32*
|
|
%val = load i32* %bcmyptr, align 4
|
|
%comp = icmp eq i32 %val, 48
|
|
br i1 %comp, label %loop.body4, label %loop.body5
|
|
|
|
loop.body4:
|
|
br i1 undef, label %loop.header, label %loop.body5
|
|
|
|
loop.body5:
|
|
%ptr2 = load i32** undef, align 4
|
|
br label %loop.body3
|
|
}
|
|
|
|
define void @unnatural_cfg2() {
|
|
; Test that we can handle a loop with a nested natural loop *and* an unnatural
|
|
; loop. This was reduced from a crash on block placement when run over
|
|
; single-source GCC.
|
|
; CHECK: unnatural_cfg2
|
|
; CHECK: %entry
|
|
; CHECK: %loop.header
|
|
; CHECK: %loop.body1
|
|
; CHECK: %loop.body2
|
|
; CHECK: %loop.body3
|
|
; CHECK: %loop.inner1.begin
|
|
; The end block is folded with %loop.body3...
|
|
; CHECK-NOT: %loop.inner1.end
|
|
; CHECK: %loop.body4
|
|
; CHECK: %loop.inner2.begin
|
|
; The loop.inner2.end block is folded
|
|
; CHECK: %bail
|
|
|
|
entry:
|
|
br label %loop.header
|
|
|
|
loop.header:
|
|
%comp0 = icmp eq i32* undef, null
|
|
br i1 %comp0, label %bail, label %loop.body1
|
|
|
|
loop.body1:
|
|
%val0 = load i32** undef, align 4
|
|
br i1 undef, label %loop.body2, label %loop.inner1.begin
|
|
|
|
loop.body2:
|
|
br i1 undef, label %loop.body4, label %loop.body3
|
|
|
|
loop.body3:
|
|
%ptr1 = getelementptr inbounds i32* %val0, i32 0
|
|
%castptr1 = bitcast i32* %ptr1 to i32**
|
|
%val1 = load i32** %castptr1, align 4
|
|
br label %loop.inner1.begin
|
|
|
|
loop.inner1.begin:
|
|
%valphi = phi i32* [ %val2, %loop.inner1.end ], [ %val1, %loop.body3 ], [ %val0, %loop.body1 ]
|
|
%castval = bitcast i32* %valphi to i32*
|
|
%comp1 = icmp eq i32 undef, 48
|
|
br i1 %comp1, label %loop.inner1.end, label %loop.body4
|
|
|
|
loop.inner1.end:
|
|
%ptr2 = getelementptr inbounds i32* %valphi, i32 0
|
|
%castptr2 = bitcast i32* %ptr2 to i32**
|
|
%val2 = load i32** %castptr2, align 4
|
|
br label %loop.inner1.begin
|
|
|
|
loop.body4.dead:
|
|
br label %loop.body4
|
|
|
|
loop.body4:
|
|
%comp2 = icmp ult i32 undef, 3
|
|
br i1 %comp2, label %loop.inner2.begin, label %loop.end
|
|
|
|
loop.inner2.begin:
|
|
br i1 false, label %loop.end, label %loop.inner2.end
|
|
|
|
loop.inner2.end:
|
|
%comp3 = icmp eq i32 undef, 1769472
|
|
br i1 %comp3, label %loop.end, label %loop.inner2.begin
|
|
|
|
loop.end:
|
|
br label %loop.header
|
|
|
|
bail:
|
|
unreachable
|
|
}
|
|
|
|
define i32 @problematic_switch() {
|
|
; This function's CFG caused overlow in the machine branch probability
|
|
; calculation, triggering asserts. Make sure we don't crash on it.
|
|
; CHECK: problematic_switch
|
|
|
|
entry:
|
|
switch i32 undef, label %exit [
|
|
i32 879, label %bogus
|
|
i32 877, label %step
|
|
i32 876, label %step
|
|
i32 875, label %step
|
|
i32 874, label %step
|
|
i32 873, label %step
|
|
i32 872, label %step
|
|
i32 868, label %step
|
|
i32 867, label %step
|
|
i32 866, label %step
|
|
i32 861, label %step
|
|
i32 860, label %step
|
|
i32 856, label %step
|
|
i32 855, label %step
|
|
i32 854, label %step
|
|
i32 831, label %step
|
|
i32 830, label %step
|
|
i32 829, label %step
|
|
i32 828, label %step
|
|
i32 815, label %step
|
|
i32 814, label %step
|
|
i32 811, label %step
|
|
i32 806, label %step
|
|
i32 805, label %step
|
|
i32 804, label %step
|
|
i32 803, label %step
|
|
i32 802, label %step
|
|
i32 801, label %step
|
|
i32 800, label %step
|
|
i32 799, label %step
|
|
i32 798, label %step
|
|
i32 797, label %step
|
|
i32 796, label %step
|
|
i32 795, label %step
|
|
]
|
|
bogus:
|
|
unreachable
|
|
step:
|
|
br label %exit
|
|
exit:
|
|
%merge = phi i32 [ 3, %step ], [ 6, %entry ]
|
|
ret i32 %merge
|
|
}
|