forked from OSchip/llvm-project
140 lines
3.9 KiB
YAML
140 lines
3.9 KiB
YAML
# RUN: llc -run-pass=branch-folder %s -o - | FileCheck %s
|
|
|
|
# PR33980
|
|
|
|
# Don't form conditional tail calls when the original conditional branch has
|
|
# the same true and false destination. Otherwise, when we remove the tail call
|
|
# successor we will also remove the fallthrough successor from the CFG.
|
|
|
|
# CHECK: body: |
|
|
# CHECK: bb.0.entry:
|
|
# CHECK: successors: %bb.1(0x40000000)
|
|
# CHECK: liveins: $edi
|
|
# CHECK: CMP32ri8 killed $edi, 2, implicit-def $eflags
|
|
# CHECK: TCRETURNdi64cc @mergeable_conditional_tailcall
|
|
|
|
# This was the unconditional branch to a dead MBB that we left behind before
|
|
# this bug was fixed.
|
|
# CHECK-NOT: JMP_1 %bb.-1
|
|
|
|
--- |
|
|
; ModuleID = 't.ll'
|
|
source_filename = "t.ll"
|
|
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
|
|
target triple = "x86_64--linux"
|
|
|
|
@static_local_guard = external global i64, align 8
|
|
|
|
; Function Attrs: optsize
|
|
define void @f(i32 %arg) #0 {
|
|
entry:
|
|
switch i32 %arg, label %sw.epilog [
|
|
i32 0, label %sw.bb
|
|
i32 1, label %sw.bb
|
|
i32 2, label %sw.bb2
|
|
]
|
|
|
|
sw.bb: ; preds = %entry, %entry
|
|
%tmp = load atomic i8, i8* bitcast (i64* @static_local_guard to i8*) acquire, align 8
|
|
%guard.uninitialized.i = icmp eq i8 %tmp, 0
|
|
br i1 %guard.uninitialized.i, label %init.check.i, label %return, !prof !0
|
|
|
|
init.check.i: ; preds = %sw.bb
|
|
tail call void @initialize_static_local(i64* nonnull @static_local_guard)
|
|
ret void
|
|
|
|
sw.bb2: ; preds = %entry
|
|
tail call void @mergeable_conditional_tailcall()
|
|
ret void
|
|
|
|
sw.epilog: ; preds = %entry
|
|
tail call void @mergeable_conditional_tailcall()
|
|
ret void
|
|
|
|
return: ; preds = %sw.bb
|
|
ret void
|
|
}
|
|
|
|
declare void @mergeable_conditional_tailcall()
|
|
|
|
declare void @initialize_static_local(i64*)
|
|
|
|
; Function Attrs: nounwind
|
|
declare void @llvm.stackprotector(i8*, i8**) #1
|
|
|
|
attributes #0 = { optsize }
|
|
attributes #1 = { nounwind }
|
|
|
|
!0 = !{!"branch_weights", i32 1, i32 1048575}
|
|
|
|
...
|
|
---
|
|
name: f
|
|
alignment: 0
|
|
exposesReturnsTwice: false
|
|
legalized: false
|
|
regBankSelected: false
|
|
selected: false
|
|
tracksRegLiveness: true
|
|
registers:
|
|
liveins:
|
|
- { reg: '$edi', virtual-reg: '' }
|
|
frameInfo:
|
|
isFrameAddressTaken: false
|
|
isReturnAddressTaken: false
|
|
hasStackMap: false
|
|
hasPatchPoint: false
|
|
stackSize: 0
|
|
offsetAdjustment: 0
|
|
maxAlignment: 0
|
|
adjustsStack: false
|
|
hasCalls: false
|
|
stackProtector: ''
|
|
maxCallFrameSize: 0
|
|
hasOpaqueSPAdjustment: false
|
|
hasVAStart: false
|
|
hasMustTailInVarArgFunc: false
|
|
savePoint: ''
|
|
restorePoint: ''
|
|
fixedStack:
|
|
stack:
|
|
constants:
|
|
body: |
|
|
bb.0.entry:
|
|
successors: %bb.2(0x40000000), %bb.1(0x40000000)
|
|
liveins: $edi
|
|
|
|
CMP32ri8 killed $edi, 2, implicit-def $eflags
|
|
JB_1 %bb.2, implicit $eflags
|
|
JMP_1 %bb.1
|
|
|
|
bb.1.entry:
|
|
successors: %bb.4(0x40000000), %bb.5(0x40000000)
|
|
liveins: $eflags
|
|
|
|
JE_1 %bb.4, implicit killed $eflags
|
|
JMP_1 %bb.5
|
|
|
|
bb.2.sw.bb:
|
|
successors: %bb.3(0x00000800), %bb.6(0x7ffff800)
|
|
|
|
$al = ACQUIRE_MOV8rm $rip, 1, $noreg, @static_local_guard, $noreg :: (volatile load acquire 1 from `i8* bitcast (i64* @static_local_guard to i8*)`, align 8)
|
|
TEST8rr killed $al, $al, implicit-def $eflags
|
|
JNE_1 %bb.6, implicit killed $eflags
|
|
JMP_1 %bb.3
|
|
|
|
bb.3.init.check.i:
|
|
dead $edi = MOV32ri64 @static_local_guard, implicit-def $rdi
|
|
TCRETURNdi64 @initialize_static_local, 0, csr_64, implicit $rsp, implicit $rdi
|
|
|
|
bb.4.sw.bb2:
|
|
TCRETURNdi64 @mergeable_conditional_tailcall, 0, csr_64, implicit $rsp
|
|
|
|
bb.5.sw.epilog:
|
|
TCRETURNdi64 @mergeable_conditional_tailcall, 0, csr_64, implicit $rsp
|
|
|
|
bb.6.return:
|
|
RET 0
|
|
|
|
...
|