llvm-6502/test/Transforms/StructurizeCFG/nested-loop-order.ll
Tom Stellard 7c038bc15f StructurizeCFG: Use a reverse post-order traversal
We were previously doing a post-order traversal and operating on the
list in reverse, however this would occasionaly cause backedges for
loops to be visited before some of the other blocks in the loop.

We know use a reverse post-order traversal, which avoids this issue.

The reverse post-order traversal is not completely ideal, so we need
to manually fixup the list to ensure that inner loop backedges are
visited before outer loop backedges.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228186 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 20:49:44 +00:00

80 lines
2.5 KiB
LLVM

; RUN: opt -S -structurizecfg %s -o - | FileCheck %s
define void @main(float addrspace(1)* %out) {
; CHECK: main_body:
; CHECK: br label %LOOP.outer
main_body:
br label %LOOP.outer
; CHECK: LOOP.outer:
; CHECK: br label %LOOP
LOOP.outer: ; preds = %ENDIF28, %main_body
%temp8.0.ph = phi float [ 0.000000e+00, %main_body ], [ %tmp35, %ENDIF28 ]
%temp4.0.ph = phi i32 [ 0, %main_body ], [ %tmp20, %ENDIF28 ]
br label %LOOP
; CHECK: LOOP:
; br i1 %{{[0-9]+}}, label %ENDIF, label %Flow
LOOP: ; preds = %IF29, %LOOP.outer
%temp4.0 = phi i32 [ %temp4.0.ph, %LOOP.outer ], [ %tmp20, %IF29 ]
%tmp20 = add i32 %temp4.0, 1
%tmp22 = icmp sgt i32 %tmp20, 3
br i1 %tmp22, label %ENDLOOP, label %ENDIF
; CHECK: Flow3
; CHECK: br i1 %{{[0-9]+}}, label %ENDLOOP, label %LOOP.outer
; CHECK: ENDLOOP:
; CHECK: ret void
ENDLOOP: ; preds = %ENDIF28, %IF29, %LOOP
%temp8.1 = phi float [ %temp8.0.ph, %LOOP ], [ %temp8.0.ph, %IF29 ], [ %tmp35, %ENDIF28 ]
%tmp23 = icmp eq i32 %tmp20, 3
%.45 = select i1 %tmp23, float 0.000000e+00, float 1.000000e+00
store float %.45, float addrspace(1)* %out
ret void
; CHECK: ENDIF:
; CHECK: br i1 %tmp31, label %IF29, label %Flow1
ENDIF: ; preds = %LOOP
%tmp31 = icmp sgt i32 %tmp20, 1
br i1 %tmp31, label %IF29, label %ENDIF28
; CHECK: Flow:
; CHECK br i1 %{{[0-9]+}}, label %Flow, label %LOOP
; CHECK: IF29:
; CHECK: br label %Flow1
IF29: ; preds = %ENDIF
%tmp32 = icmp sgt i32 %tmp20, 2
br i1 %tmp32, label %ENDLOOP, label %LOOP
; CHECK: Flow1:
; CHECK: br label %Flow
; CHECK: Flow2:
; CHECK: br i1 %{{[0-9]+}}, label %ENDIF28, label %Flow3
; CHECK: ENDIF28:
; CHECK: br label %Flow3
ENDIF28: ; preds = %ENDIF
%tmp35 = fadd float %temp8.0.ph, 1.0
%tmp36 = icmp sgt i32 %tmp20, 2
br i1 %tmp36, label %ENDLOOP, label %LOOP.outer
}
; Function Attrs: nounwind readnone
declare <4 x float> @llvm.SI.vs.load.input(<16 x i8>, i32, i32) #1
; Function Attrs: readnone
declare float @llvm.AMDIL.clamp.(float, float, float) #2
declare void @llvm.SI.export(i32, i32, i32, i32, i32, float, float, float, float)
attributes #0 = { "ShaderType"="1" "enable-no-nans-fp-math"="true" "unsafe-fp-math"="true" }
attributes #1 = { nounwind readnone }
attributes #2 = { readnone }
!0 = !{!1, !1, i64 0, i32 1}
!1 = !{!"const", null}