mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-10-19 11:02:59 +02:00
2a20a3f170
The cost of predicating a diamond is only the instructions that are not shared between the two branches. Additionally If a predicate clobbering instruction occurs in the shared portion of the branches (e.g. a cond move), it may still be possible to if convert the sub-cfg. This change handles these two facts by rescanning the non-shared portion of a diamond sub-cfg to recalculate both the predication cost and whether both blocks are pred-clobbering. Fixed 2 bugs before recommitting. Branch instructions must be compared and found identical before diamond conversion. Also, predicate-clobbering instructions in the shared prefix disqualifies a potential diamond conversion. Includes tests for both. llvm-svn: 279670
37 lines
1.2 KiB
LLVM
37 lines
1.2 KiB
LLVM
; RUN: llc -O2 -o - %s | FileCheck %s
|
|
target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
|
|
target triple = "thumbv7-unknown-linux-gnueabihf"
|
|
|
|
; Function Attrs: argmemonly nounwind
|
|
declare void @llvm.lifetime.start(i64, i8* nocapture) #0
|
|
|
|
; Function Attrs: nounwind
|
|
declare void @_ZNSaIcEC2Ev() unnamed_addr #0 align 2
|
|
|
|
declare void @_ZNSsC1EPKcRKSaIcE() unnamed_addr #0
|
|
|
|
; It isn't valid to If-Convert the following function, even though the calls
|
|
; are in common. The calls clobber the predicate info.
|
|
; CHECK: cbnz r{{[0-9]+}}, .LBB0_2
|
|
; CHECK: BB#1
|
|
; CHECK: .LBB0_2
|
|
; Function Attrs: nounwind
|
|
define hidden void @_ZN4llvm14DOTGraphTraitsIPNS_13ScheduleDAGMIEE17getEdgeAttributesEPKNS_5SUnitENS_13SUnitIteratorEPKNS_11ScheduleDAGE() #0 align 2 {
|
|
br i1 undef, label %1, label %2
|
|
|
|
; <label>:1: ; preds = %0
|
|
call void @_ZNSaIcEC2Ev() #0
|
|
call void @_ZNSsC1EPKcRKSaIcE()
|
|
br label %3
|
|
|
|
; <label>:2: ; preds = %0
|
|
call void @llvm.lifetime.start(i64 1, i8* undef) #0
|
|
call void @_ZNSaIcEC2Ev() #0
|
|
br label %3
|
|
|
|
; <label>:3: ; preds = %2, %1
|
|
ret void
|
|
}
|
|
|
|
attributes #0 = { nounwind }
|