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      1 ; RUN: llc -mtriple=powerpc64le-unknown-linux-gnu -mcpu=pwr8 %s -o - | FileCheck %s --check-prefix=CHECK --check-prefix=ENABLE
      2 ; RUN: llc -mtriple=powerpc64le-unknown-linux-gnu %s -o - -enable-shrink-wrap=false |  FileCheck %s --check-prefix=CHECK --check-prefix=DISABLE
      3 ;
      4 ; Note: Lots of tests use inline asm instead of regular calls.
      5 ; This allows to have a better control on what the allocation will do.
      6 ; Otherwise, we may have spill right in the entry block, defeating
      7 ; shrink-wrapping. Moreover, some of the inline asm statement (nop)
      8 ; are here to ensure that the related paths do not end up as critical
      9 ; edges.
     10 
     11 
     12 ; Initial motivating example: Simple diamond with a call just on one side.
     13 ; CHECK-LABEL: foo:
     14 ;
     15 ; Compare the arguments and return
     16 ; No prologue needed.
     17 ; ENABLE: cmpw 0, 3, 4
     18 ; ENABLE-NEXT: bgelr 0
     19 ;
     20 ; Prologue code.
     21 ;  At a minimum, we save/restore the link register. Other registers may be saved
     22 ;  as well. 
     23 ; CHECK: mflr 
     24 ;
     25 ; Compare the arguments and jump to exit.
     26 ; After the prologue is set.
     27 ; DISABLE: cmpw 0, 3, 4
     28 ; DISABLE-NEXT: bge 0, .[[EXIT_LABEL:LBB[0-9_]+]]
     29 ;
     30 ; Store %a on the stack
     31 ; CHECK: stw 3, {{[0-9]+([0-9]+)}}
     32 ; Set the alloca address in the second argument.
     33 ; CHECK-NEXT: addi 4, 1, {{[0-9]+}}
     34 ; Set the first argument to zero.
     35 ; CHECK-NEXT: li 3, 0
     36 ; CHECK-NEXT: bl doSomething
     37 ;
     38 ; With shrink-wrapping, epilogue is just after the call.
     39 ; Restore the link register and return.
     40 ; Note that there could be other epilog code before the link register is 
     41 ; restored but we will not check for it here.
     42 ; ENABLE: mtlr
     43 ; ENABLE-NEXT: blr
     44 ;
     45 ; DISABLE: [[EXIT_LABEL]]:
     46 ;
     47 ; Without shrink-wrapping, epilogue is in the exit block.
     48 ; Epilogue code. (What we pop does not matter.)
     49 ; DISABLE: mtlr {{[0-9]+}}
     50 ; DISABLE-NEXT: blr
     51 ;
     52 
     53 define i32 @foo(i32 %a, i32 %b) {
     54   %tmp = alloca i32, align 4
     55   %tmp2 = icmp slt i32 %a, %b
     56   br i1 %tmp2, label %true, label %false
     57 
     58 true:
     59   store i32 %a, i32* %tmp, align 4
     60   %tmp4 = call i32 @doSomething(i32 0, i32* %tmp)
     61   br label %false
     62 
     63 false:
     64   %tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %0 ]
     65   ret i32 %tmp.0
     66 }
     67 
     68 ; Function Attrs: optsize
     69 declare i32 @doSomething(i32, i32*)
     70 
     71 
     72 
     73 ; Check that we do not perform the restore inside the loop whereas the save
     74 ; is outside.
     75 ; CHECK-LABEL: freqSaveAndRestoreOutsideLoop:
     76 ;
     77 ; Shrink-wrapping allows to skip the prologue in the else case.
     78 ; ENABLE: cmplwi 0, 3, 0
     79 ; ENABLE: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
     80 ;
     81 ; Prologue code.
     82 ; Make sure we save the link register
     83 ; CHECK: mflr {{[0-9]+}}
     84 ;
     85 ; DISABLE: cmplwi 0, 3, 0
     86 ; DISABLE: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
     87 ;
     88 ; Loop preheader
     89 ; CHECK-DAG: li [[SUM:[0-9]+]], 0
     90 ; CHECK-DAG: li [[IV:[0-9]+]], 10
     91 ; 
     92 ; Loop body
     93 ; CHECK: .[[LOOP:LBB[0-9_]+]]: # %for.body
     94 ; CHECK: bl something
     95 ; CHECK-DAG: addi [[IV]], [[IV]], -1
     96 ; CHECK-DAG: add [[SUM]], 3, [[SUM]] 
     97 ; CHECK-NEXT: cmplwi [[IV]], 0
     98 ; CHECK-NEXT: bne 0, .[[LOOP]]
     99 ;
    100 ; Next BB.
    101 ; CHECK: slwi 3, [[SUM]], 3
    102 ;
    103 ; Jump to epilogue.
    104 ; DISABLE: b .[[EPILOG_BB:LBB[0-9_]+]]
    105 ;
    106 ; DISABLE: .[[ELSE_LABEL]]: # %if.else
    107 ; Shift second argument by one and store into returned register.
    108 ; DISABLE: slwi 3, 4, 1
    109 ; DISABLE: .[[EPILOG_BB]]: # %if.end
    110 ;
    111 ; Epilogue code.
    112 ; CHECK: mtlr {{[0-9]+}}
    113 ; CHECK-NEXT: blr
    114 ;
    115 ; ENABLE: .[[ELSE_LABEL]]: # %if.else
    116 ; Shift second argument by one and store into returned register.
    117 ; ENABLE: slwi 3, 4, 1
    118 ; ENABLE-NEXT: blr
    119 define i32 @freqSaveAndRestoreOutsideLoop(i32 %cond, i32 %N) {
    120 entry:
    121   %tobool = icmp eq i32 %cond, 0
    122   br i1 %tobool, label %if.else, label %for.preheader
    123 
    124 for.preheader:
    125   tail call void asm "nop", ""()
    126   br label %for.body
    127 
    128 for.body:                                         ; preds = %entry, %for.body
    129   %i.05 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
    130   %sum.04 = phi i32 [ %add, %for.body ], [ 0, %for.preheader ]
    131   %call = tail call i32 bitcast (i32 (...)* @something to i32 ()*)()
    132   %add = add nsw i32 %call, %sum.04
    133   %inc = add nuw nsw i32 %i.05, 1
    134   %exitcond = icmp eq i32 %inc, 10
    135   br i1 %exitcond, label %for.end, label %for.body
    136 
    137 for.end:                                          ; preds = %for.body
    138   %shl = shl i32 %add, 3
    139   br label %if.end
    140 
    141 if.else:                                          ; preds = %entry
    142   %mul = shl nsw i32 %N, 1
    143   br label %if.end
    144 
    145 if.end:                                           ; preds = %if.else, %for.end
    146   %sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
    147   ret i32 %sum.1
    148 }
    149 
    150 declare i32 @something(...)
    151 
    152 ; Check that we do not perform the shrink-wrapping inside the loop even
    153 ; though that would be legal. The cost model must prevent that.
    154 ; CHECK-LABEL: freqSaveAndRestoreOutsideLoop2:
    155 ; Prologue code.
    156 ; Make sure we save the link register before the call
    157 ; CHECK: mflr {{[0-9]+}}
    158 ;
    159 ; Loop preheader
    160 ; CHECK-DAG: li [[SUM:[0-9]+]], 0
    161 ; CHECK-DAG: li [[IV:[0-9]+]], 10
    162 ; 
    163 ; Loop body
    164 ; CHECK: .[[LOOP:LBB[0-9_]+]]: # %for.body
    165 ; CHECK: bl something
    166 ; CHECK-DAG: addi [[IV]], [[IV]], -1
    167 ; CHECK-DAG: add [[SUM]], 3, [[SUM]] 
    168 ; CHECK-NEXT: cmplwi [[IV]], 0
    169 ; CHECK-NEXT: bne 0, .[[LOOP]]
    170 ;
    171 ; Next BB
    172 ; CHECK: %for.exit
    173 ; CHECK: mtlr {{[0-9]+}}
    174 ; CHECK-NEXT: blr
    175 define i32 @freqSaveAndRestoreOutsideLoop2(i32 %cond) {
    176 entry:
    177   br label %for.preheader
    178 
    179 for.preheader:
    180   tail call void asm "nop", ""()
    181   br label %for.body
    182 
    183 for.body:                                         ; preds = %for.body, %entry
    184   %i.04 = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]
    185   %sum.03 = phi i32 [ 0, %for.preheader ], [ %add, %for.body ]
    186   %call = tail call i32 bitcast (i32 (...)* @something to i32 ()*)()
    187   %add = add nsw i32 %call, %sum.03
    188   %inc = add nuw nsw i32 %i.04, 1
    189   %exitcond = icmp eq i32 %inc, 10
    190   br i1 %exitcond, label %for.exit, label %for.body
    191 
    192 for.exit:
    193   tail call void asm "nop", ""()
    194   br label %for.end
    195 
    196 for.end:                                          ; preds = %for.body
    197   ret i32 %add
    198 }
    199 
    200 
    201 ; Check with a more complex case that we do not have save within the loop and
    202 ; restore outside.
    203 ; CHECK-LABEL: loopInfoSaveOutsideLoop:
    204 ;
    205 ; ENABLE: cmplwi 0, 3, 0
    206 ; ENABLE-NEXT: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
    207 ;
    208 ; Prologue code.
    209 ; Make sure we save the link register 
    210 ; CHECK: mflr {{[0-9]+}}
    211 ;
    212 ; DISABLE: cmplwi 0, 3, 0
    213 ; DISABLE-NEXT: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
    214 ;
    215 ; Loop preheader
    216 ; CHECK-DAG: li [[SUM:[0-9]+]], 0
    217 ; CHECK-DAG: li [[IV:[0-9]+]], 10
    218 ; 
    219 ; Loop body
    220 ; CHECK: .[[LOOP:LBB[0-9_]+]]: # %for.body
    221 ; CHECK: bl something
    222 ; CHECK-DAG: addi [[IV]], [[IV]], -1
    223 ; CHECK-DAG: add [[SUM]], 3, [[SUM]] 
    224 ; CHECK-NEXT: cmplwi [[IV]], 0
    225 ; CHECK-NEXT: bne 0, .[[LOOP]]
    226 ; 
    227 ; Next BB
    228 ; CHECK: bl somethingElse 
    229 ; CHECK: slwi 3, [[SUM]], 3
    230 ;
    231 ; Jump to epilogue
    232 ; DISABLE: b .[[EPILOG_BB:LBB[0-9_]+]]
    233 ;
    234 ; DISABLE: .[[ELSE_LABEL]]: # %if.else
    235 ; Shift second argument by one and store into returned register.
    236 ; DISABLE: slwi 3, 4, 1
    237 ;
    238 ; DISABLE: .[[EPILOG_BB]]: # %if.end
    239 ; Epilog code
    240 ; CHECK: mtlr {{[0-9]+}}
    241 ; CHECK-NEXT: blr
    242 ; 
    243 ; ENABLE: .[[ELSE_LABEL]]: # %if.else
    244 ; Shift second argument by one and store into returned register.
    245 ; ENABLE: slwi 3, 4, 1
    246 ; ENABLE-NEXT: blr
    247 define i32 @loopInfoSaveOutsideLoop(i32 %cond, i32 %N) {
    248 entry:
    249   %tobool = icmp eq i32 %cond, 0
    250   br i1 %tobool, label %if.else, label %for.preheader
    251 
    252 for.preheader:
    253   tail call void asm "nop", ""()
    254   br label %for.body
    255 
    256 for.body:                                         ; preds = %entry, %for.body
    257   %i.05 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
    258   %sum.04 = phi i32 [ %add, %for.body ], [ 0, %for.preheader ]
    259   %call = tail call i32 bitcast (i32 (...)* @something to i32 ()*)()
    260   %add = add nsw i32 %call, %sum.04
    261   %inc = add nuw nsw i32 %i.05, 1
    262   %exitcond = icmp eq i32 %inc, 10
    263   br i1 %exitcond, label %for.end, label %for.body
    264 
    265 for.end:                                          ; preds = %for.body
    266   tail call void bitcast (void (...)* @somethingElse to void ()*)()
    267   %shl = shl i32 %add, 3
    268   br label %if.end
    269 
    270 if.else:                                          ; preds = %entry
    271   %mul = shl nsw i32 %N, 1
    272   br label %if.end
    273 
    274 if.end:                                           ; preds = %if.else, %for.end
    275   %sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
    276   ret i32 %sum.1
    277 }
    278 
    279 declare void @somethingElse(...)
    280 
    281 ; Check with a more complex case that we do not have restore within the loop and
    282 ; save outside.
    283 ; CHECK-LABEL: loopInfoRestoreOutsideLoop:
    284 ;
    285 ; ENABLE: cmplwi 0, 3, 0
    286 ; ENABLE-NEXT: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
    287 ;
    288 ; Prologue code.
    289 ; Make sure we save the link register
    290 ; CHECK: mflr {{[0-9]+}}
    291 ;
    292 ; DISABLE: cmplwi 0, 3, 0
    293 ; DISABLE-NEXT: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
    294 ;
    295 ; CHECK: bl somethingElse
    296 ;
    297 ; Loop preheader
    298 ; CHECK-DAG: li [[SUM:[0-9]+]], 0
    299 ; CHECK-DAG: li [[IV:[0-9]+]], 10
    300 ; 
    301 ; Loop body
    302 ; CHECK: .[[LOOP:LBB[0-9_]+]]: # %for.body
    303 ; CHECK: bl something
    304 ; CHECK-DAG: addi [[IV]], [[IV]], -1
    305 ; CHECK-DAG: add [[SUM]], 3, [[SUM]] 
    306 ; CHECK-NEXT: cmplwi [[IV]], 0
    307 ; CHECK-NEXT: bne 0, .[[LOOP]]
    308 ;
    309 ; Next BB. 
    310 ; slwi 3, [[SUM]], 3
    311 ;
    312 ; DISABLE: b .[[EPILOG_BB:LBB[0-9_]+]]
    313 ;
    314 ; DISABLE: .[[ELSE_LABEL]]: # %if.else
    315 ; Shift second argument by one and store into returned register.
    316 ; DISABLE: slwi 3, 4, 1
    317 ; DISABLE: .[[EPILOG_BB]]: # %if.end
    318 ;
    319 ; Epilogue code.
    320 ; CHECK: mtlr {{[0-9]+}}
    321 ; CHECK-NEXT: blr
    322 ;
    323 ; ENABLE: .[[ELSE_LABEL]]: # %if.else
    324 ; Shift second argument by one and store into returned register.
    325 ; ENABLE: slwi 3, 4, 1
    326 ; ENABLE-NEXT: blr
    327 define i32 @loopInfoRestoreOutsideLoop(i32 %cond, i32 %N) #0 {
    328 entry:
    329   %tobool = icmp eq i32 %cond, 0
    330   br i1 %tobool, label %if.else, label %if.then
    331 
    332 if.then:                                          ; preds = %entry
    333   tail call void bitcast (void (...)* @somethingElse to void ()*)()
    334   br label %for.body
    335 
    336 for.body:                                         ; preds = %for.body, %if.then
    337   %i.05 = phi i32 [ 0, %if.then ], [ %inc, %for.body ]
    338   %sum.04 = phi i32 [ 0, %if.then ], [ %add, %for.body ]
    339   %call = tail call i32 bitcast (i32 (...)* @something to i32 ()*)()
    340   %add = add nsw i32 %call, %sum.04
    341   %inc = add nuw nsw i32 %i.05, 1
    342   %exitcond = icmp eq i32 %inc, 10
    343   br i1 %exitcond, label %for.end, label %for.body
    344 
    345 for.end:                                          ; preds = %for.body
    346   %shl = shl i32 %add, 3
    347   br label %if.end
    348 
    349 if.else:                                          ; preds = %entry
    350   %mul = shl nsw i32 %N, 1
    351   br label %if.end
    352 
    353 if.end:                                           ; preds = %if.else, %for.end
    354   %sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
    355   ret i32 %sum.1
    356 }
    357 
    358 ; Check that we handle function with no frame information correctly.
    359 ; CHECK-LABEL: emptyFrame:
    360 ; CHECK: # %entry
    361 ; CHECK-NEXT: li 3, 0
    362 ; CHECK-NEXT: blr
    363 define i32 @emptyFrame() {
    364 entry:
    365   ret i32 0
    366 }
    367 
    368 
    369 ; Check that we handle inline asm correctly.
    370 ; CHECK-LABEL: inlineAsm:
    371 ;
    372 ; ENABLE: cmplwi 0, 3, 0
    373 ; ENABLE-NEXT: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
    374 ;
    375 ; Prologue code.
    376 ; Make sure we save the CSR used in the inline asm: r14
    377 ; ENABLE-DAG: li [[IV:[0-9]+]], 10
    378 ; ENABLE-DAG: std 14, -[[STACK_OFFSET:[0-9]+]](1) # 8-byte Folded Spill
    379 ;
    380 ; DISABLE: std 14, -[[STACK_OFFSET:[0-9]+]](1) # 8-byte Folded Spill
    381 ; DISABLE: cmplwi 0, 3, 0
    382 ; DISABLE-NEXT: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
    383 ; DISABLE: li [[IV:[0-9]+]], 10
    384 ;
    385 ; CHECK: nop
    386 ; CHECK: mtctr [[IV]]
    387 ;
    388 ; CHECK: .[[LOOP_LABEL:LBB[0-9_]+]]: # %for.body
    389 ; Inline asm statement.
    390 ; CHECK: addi 14, 14, 1
    391 ; CHECK: bdnz .[[LOOP_LABEL]]
    392 ;
    393 ; Epilogue code.
    394 ; CHECK: li 3, 0
    395 ; CHECK-DAG: ld 14, -[[STACK_OFFSET]](1) # 8-byte Folded Reload
    396 ; CHECK: nop
    397 ; CHECK: blr
    398 ;
    399 ; CHECK: [[ELSE_LABEL]]
    400 ; CHECK-NEXT: slwi 3, 4, 1
    401 ; DISABLE: ld 14, -[[STACK_OFFSET]](1) # 8-byte Folded Reload
    402 ; CHECK-NEXT blr
    403 ; 
    404 define i32 @inlineAsm(i32 %cond, i32 %N) {
    405 entry:
    406   %tobool = icmp eq i32 %cond, 0
    407   br i1 %tobool, label %if.else, label %for.preheader
    408 
    409 for.preheader:
    410   tail call void asm "nop", ""()
    411   br label %for.body
    412 
    413 for.body:                                         ; preds = %entry, %for.body
    414   %i.03 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
    415   tail call void asm "addi 14, 14, 1", "~{r14}"()
    416   %inc = add nuw nsw i32 %i.03, 1
    417   %exitcond = icmp eq i32 %inc, 10
    418   br i1 %exitcond, label %for.exit, label %for.body
    419 
    420 for.exit:
    421   tail call void asm "nop", ""()
    422   br label %if.end
    423 
    424 if.else:                                          ; preds = %entry
    425   %mul = shl nsw i32 %N, 1
    426   br label %if.end
    427 
    428 if.end:                                           ; preds = %for.body, %if.else
    429   %sum.0 = phi i32 [ %mul, %if.else ], [ 0, %for.exit ]
    430   ret i32 %sum.0
    431 }
    432 
    433 
    434 ; Check that we handle calls to variadic functions correctly.
    435 ; CHECK-LABEL: callVariadicFunc:
    436 ;
    437 ; ENABLE: cmplwi 0, 3, 0
    438 ; ENABLE-NEXT: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
    439 ;
    440 ; Prologue code.
    441 ; CHECK: mflr {{[0-9]+}}
    442 ; 
    443 ; DISABLE: cmplwi 0, 3, 0
    444 ; DISABLE-NEXT: beq 0, .[[ELSE_LABEL:LBB[0-9_]+]]
    445 ;
    446 ; Setup of the varags.
    447 ; CHECK: mr 4, 3
    448 ; CHECK-NEXT: mr 5, 3
    449 ; CHECK-NEXT: mr 6, 3
    450 ; CHECK-NEXT: mr 7, 3
    451 ; CHECK-NEXT: mr 8, 3
    452 ; CHECK-NEXT: mr 9, 3
    453 ; CHECK-NEXT: bl someVariadicFunc
    454 ; CHECK: slwi 3, 3, 3
    455 ; DISABLE: b .[[EPILOGUE_BB:LBB[0-9_]+]]
    456 ;
    457 ; ENABLE: mtlr {{[0-9]+}}
    458 ; ENABLE-NEXT: blr
    459 ;
    460 ; CHECK: .[[ELSE_LABEL]]: # %if.else
    461 ; CHECK-NEXT: slwi 3, 4, 1
    462 ; 
    463 ; DISABLE: .[[EPILOGUE_BB]]: # %if.end
    464 ; DISABLE: mtlr
    465 ; CHECK: blr
    466 define i32 @callVariadicFunc(i32 %cond, i32 %N) {
    467 entry:
    468   %tobool = icmp eq i32 %cond, 0
    469   br i1 %tobool, label %if.else, label %if.then
    470 
    471 if.then:                                          ; preds = %entry
    472   %call = tail call i32 (i32, ...) @someVariadicFunc(i32 %N, i32 %N, i32 %N, i32 %N, i32 %N, i32 %N, i32 %N)
    473   %shl = shl i32 %call, 3
    474   br label %if.end
    475 
    476 if.else:                                          ; preds = %entry
    477   %mul = shl nsw i32 %N, 1
    478   br label %if.end
    479 
    480 if.end:                                           ; preds = %if.else, %if.then
    481   %sum.0 = phi i32 [ %shl, %if.then ], [ %mul, %if.else ]
    482   ret i32 %sum.0
    483 }
    484 
    485 declare i32 @someVariadicFunc(i32, ...)
    486 
    487 
    488 
    489 ; Make sure we do not insert unreachable code after noreturn function.
    490 ; Although this is not incorrect to insert such code, it is useless
    491 ; and it hurts the binary size.
    492 ;
    493 ; CHECK-LABEL: noreturn:
    494 ; DISABLE: mflr {{[0-9]+}}
    495 ;
    496 ; CHECK: cmplwi 3, 0
    497 ; CHECK-NEXT: bne{{[-]?}} 0, .[[ABORT:LBB[0-9_]+]]
    498 ;
    499 ; CHECK: li 3, 42
    500 ;
    501 ; DISABLE: mtlr {{[0-9]+}}
    502 ;
    503 ; CHECK-NEXT: blr
    504 ;
    505 ; CHECK: .[[ABORT]]: # %if.abort
    506 ;
    507 ; ENABLE: mflr {{[0-9]+}}
    508 ;
    509 ; CHECK: bl abort
    510 ; ENABLE-NOT: mtlr {{[0-9]+}}
    511 define i32 @noreturn(i8 signext %bad_thing) {
    512 entry:
    513   %tobool = icmp eq i8 %bad_thing, 0
    514   br i1 %tobool, label %if.end, label %if.abort
    515 
    516 if.abort:
    517   tail call void @abort() #0
    518   unreachable
    519 
    520 if.end:
    521   ret i32 42
    522 }
    523 
    524 declare void @abort() #0
    525 
    526 attributes #0 = { noreturn nounwind }
    527 
    528 
    529 ; Make sure that we handle infinite loops properly When checking that the Save
    530 ; and Restore blocks are control flow equivalent, the loop searches for the
    531 ; immediate (post) dominator for the (restore) save blocks. When either the Save
    532 ; or Restore block is located in an infinite loop the only immediate (post)
    533 ; dominator is itself. In this case, we cannot perform shrink wrapping, but we
    534 ; should return gracefully and continue compilation.
    535 ; The only condition for this test is the compilation finishes correctly.
    536 ; 
    537 ; CHECK-LABEL: infiniteloop
    538 ; CHECK: blr
    539 define void @infiniteloop() {
    540 entry:
    541   br i1 undef, label %if.then, label %if.end
    542 
    543 if.then:
    544   %ptr = alloca i32, i32 4
    545   br label %for.body
    546 
    547 for.body:                                         ; preds = %for.body, %entry
    548   %sum.03 = phi i32 [ 0, %if.then ], [ %add, %for.body ]
    549   %call = tail call i32 bitcast (i32 (...)* @something to i32 ()*)()
    550   %add = add nsw i32 %call, %sum.03
    551   store i32 %add, i32* %ptr
    552   br label %for.body
    553 
    554 if.end:
    555   ret void
    556 }
    557 
    558 ; Another infinite loop test this time with a body bigger than just one block.
    559 ; CHECK-LABEL: infiniteloop2
    560 ; CHECK: blr
    561 define void @infiniteloop2() {
    562 entry:
    563   br i1 undef, label %if.then, label %if.end
    564 
    565 if.then:
    566   %ptr = alloca i32, i32 4
    567   br label %for.body
    568 
    569 for.body:                                         ; preds = %for.body, %entry
    570   %sum.03 = phi i32 [ 0, %if.then ], [ %add, %body1 ], [ 1, %body2]
    571   %call = tail call i32 asm "mftb $0, 268", "=r,~{r14}"()
    572   %add = add nsw i32 %call, %sum.03
    573   store i32 %add, i32* %ptr
    574   br i1 undef, label %body1, label %body2
    575 
    576 body1:
    577   tail call void asm sideeffect "nop", "~{r14}"()
    578   br label %for.body
    579 
    580 body2:
    581   tail call void asm sideeffect "nop", "~{r14}"()
    582   br label %for.body
    583 
    584 if.end:
    585   ret void
    586 }
    587 
    588 ; Another infinite loop test this time with two nested infinite loop.
    589 ; CHECK-LABEL: infiniteloop3
    590 ; CHECK: # %end
    591 define void @infiniteloop3() {
    592 entry:
    593   br i1 undef, label %loop2a, label %body
    594 
    595 body:                                             ; preds = %entry
    596   br i1 undef, label %loop2a, label %end
    597 
    598 loop1:                                            ; preds = %loop2a, %loop2b
    599   %var.phi = phi i32* [ %next.phi, %loop2b ], [ %var, %loop2a ]
    600   %next.phi = phi i32* [ %next.load, %loop2b ], [ %next.var, %loop2a ]
    601   %0 = icmp eq i32* %var, null
    602   %next.load = load i32*, i32** undef
    603   br i1 %0, label %loop2a, label %loop2b
    604 
    605 loop2a:                                           ; preds = %loop1, %body, %entry
    606   %var = phi i32* [ null, %body ], [ null, %entry ], [ %next.phi, %loop1 ]
    607   %next.var = phi i32* [ undef, %body ], [ null, %entry ], [ %next.load, %loop1 ]
    608   br label %loop1
    609 
    610 loop2b:                                           ; preds = %loop1
    611   %gep1 = bitcast i32* %var.phi to i32*
    612   %next.ptr = bitcast i32* %gep1 to i32**
    613   store i32* %next.phi, i32** %next.ptr
    614   br label %loop1
    615 
    616 end:
    617   ret void
    618 }
    619 
    620 @columns = external global [0 x i32], align 4
    621 @lock = common global i32 0, align 4
    622 @htindex = common global i32 0, align 4
    623 @stride = common global i32 0, align 4
    624 @ht = common global i32* null, align 8
    625 @he = common global i8* null, align 8
    626 
    627 ; Test for a bug that was caused when save point was equal to restore point.
    628 ; Function Attrs: nounwind
    629 ; CHECK-LABEL: transpose
    630 ;
    631 ; Store of callee-save register saved by shrink wrapping
    632 ; CHECK: std [[CSR:[0-9]+]], -[[STACK_OFFSET:[0-9]+]](1) # 8-byte Folded Spill
    633 ;
    634 ; Reload of callee-save register
    635 ; CHECK: ld [[CSR]], -[[STACK_OFFSET]](1) # 8-byte Folded Reload
    636 ;
    637 ; Ensure no subsequent uses of callee-save register before end of function
    638 ; CHECK-NOT: {{[a-z]+}} [[CSR]]
    639 ; CHECK: blr
    640 define signext i32 @transpose() {
    641 entry:
    642   %0 = load i32, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @columns, i64 0, i64 1), align 4
    643   %shl.i = shl i32 %0, 7
    644   %1 = load i32, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @columns, i64 0, i64 2), align 4
    645   %or.i = or i32 %shl.i, %1
    646   %shl1.i = shl i32 %or.i, 7
    647   %2 = load i32, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @columns, i64 0, i64 3), align 4
    648   %or2.i = or i32 %shl1.i, %2
    649   %3 = load i32, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @columns, i64 0, i64 7), align 4
    650   %shl3.i = shl i32 %3, 7
    651   %4 = load i32, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @columns, i64 0, i64 6), align 4
    652   %or4.i = or i32 %shl3.i, %4
    653   %shl5.i = shl i32 %or4.i, 7
    654   %5 = load i32, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @columns, i64 0, i64 5), align 4
    655   %or6.i = or i32 %shl5.i, %5
    656   %cmp.i = icmp ugt i32 %or2.i, %or6.i
    657   br i1 %cmp.i, label %cond.true.i, label %cond.false.i
    658 
    659 cond.true.i:
    660   %shl7.i = shl i32 %or2.i, 7
    661   %6 = load i32, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @columns, i64 0, i64 4), align 4
    662   %or8.i = or i32 %6, %shl7.i
    663   %conv.i = zext i32 %or8.i to i64
    664   %shl9.i = shl nuw nsw i64 %conv.i, 21
    665   %conv10.i = zext i32 %or6.i to i64
    666   %or11.i = or i64 %shl9.i, %conv10.i
    667   br label %hash.exit
    668 
    669 cond.false.i:
    670   %shl12.i = shl i32 %or6.i, 7
    671   %7 = load i32, i32* getelementptr inbounds ([0 x i32], [0 x i32]* @columns, i64 0, i64 4), align 4
    672   %or13.i = or i32 %7, %shl12.i
    673   %conv14.i = zext i32 %or13.i to i64
    674   %shl15.i = shl nuw nsw i64 %conv14.i, 21
    675   %conv16.i = zext i32 %or2.i to i64
    676   %or17.i = or i64 %shl15.i, %conv16.i
    677   br label %hash.exit
    678 
    679 hash.exit:
    680   %cond.i = phi i64 [ %or11.i, %cond.true.i ], [ %or17.i, %cond.false.i ]
    681   %shr.29.i = lshr i64 %cond.i, 17
    682   %conv18.i = trunc i64 %shr.29.i to i32
    683   store i32 %conv18.i, i32* @lock, align 4
    684   %rem.i = srem i64 %cond.i, 1050011
    685   %conv19.i = trunc i64 %rem.i to i32
    686   store i32 %conv19.i, i32* @htindex, align 4
    687   %rem20.i = urem i32 %conv18.i, 179
    688   %add.i = or i32 %rem20.i, 131072
    689   store i32 %add.i, i32* @stride, align 4
    690   %8 = load i32*, i32** @ht, align 8
    691   %arrayidx = getelementptr inbounds i32, i32* %8, i64 %rem.i
    692   %9 = load i32, i32* %arrayidx, align 4
    693   %cmp1 = icmp eq i32 %9, %conv18.i
    694   br i1 %cmp1, label %if.then, label %if.end
    695 
    696 if.then:
    697   %idxprom.lcssa = phi i64 [ %rem.i, %hash.exit ], [ %idxprom.1, %if.end ], [ %idxprom.2, %if.end.1 ], [ %idxprom.3, %if.end.2 ], [ %idxprom.4, %if.end.3 ], [ %idxprom.5, %if.end.4 ], [ %idxprom.6, %if.end.5 ], [ %idxprom.7, %if.end.6 ]
    698   %10 = load i8*, i8** @he, align 8
    699   %arrayidx3 = getelementptr inbounds i8, i8* %10, i64 %idxprom.lcssa
    700   %11 = load i8, i8* %arrayidx3, align 1
    701   %conv = sext i8 %11 to i32
    702   br label %cleanup
    703 
    704 if.end:
    705   %add = add nsw i32 %add.i, %conv19.i
    706   %cmp4 = icmp sgt i32 %add, 1050010
    707   %sub = add nsw i32 %add, -1050011
    708   %sub.add = select i1 %cmp4, i32 %sub, i32 %add
    709   %idxprom.1 = sext i32 %sub.add to i64
    710   %arrayidx.1 = getelementptr inbounds i32, i32* %8, i64 %idxprom.1
    711   %12 = load i32, i32* %arrayidx.1, align 4
    712   %cmp1.1 = icmp eq i32 %12, %conv18.i
    713   br i1 %cmp1.1, label %if.then, label %if.end.1
    714 
    715 cleanup:
    716   %retval.0 = phi i32 [ %conv, %if.then ], [ -128, %if.end.6 ]
    717   ret i32 %retval.0
    718 
    719 if.end.1:
    720   %add.1 = add nsw i32 %add.i, %sub.add
    721   %cmp4.1 = icmp sgt i32 %add.1, 1050010
    722   %sub.1 = add nsw i32 %add.1, -1050011
    723   %sub.add.1 = select i1 %cmp4.1, i32 %sub.1, i32 %add.1
    724   %idxprom.2 = sext i32 %sub.add.1 to i64
    725   %arrayidx.2 = getelementptr inbounds i32, i32* %8, i64 %idxprom.2
    726   %13 = load i32, i32* %arrayidx.2, align 4
    727   %cmp1.2 = icmp eq i32 %13, %conv18.i
    728   br i1 %cmp1.2, label %if.then, label %if.end.2
    729 
    730 if.end.2:
    731   %add.2 = add nsw i32 %add.i, %sub.add.1
    732   %cmp4.2 = icmp sgt i32 %add.2, 1050010
    733   %sub.2 = add nsw i32 %add.2, -1050011
    734   %sub.add.2 = select i1 %cmp4.2, i32 %sub.2, i32 %add.2
    735   %idxprom.3 = sext i32 %sub.add.2 to i64
    736   %arrayidx.3 = getelementptr inbounds i32, i32* %8, i64 %idxprom.3
    737   %14 = load i32, i32* %arrayidx.3, align 4
    738   %cmp1.3 = icmp eq i32 %14, %conv18.i
    739   br i1 %cmp1.3, label %if.then, label %if.end.3
    740 
    741 if.end.3:
    742   %add.3 = add nsw i32 %add.i, %sub.add.2
    743   %cmp4.3 = icmp sgt i32 %add.3, 1050010
    744   %sub.3 = add nsw i32 %add.3, -1050011
    745   %sub.add.3 = select i1 %cmp4.3, i32 %sub.3, i32 %add.3
    746   %idxprom.4 = sext i32 %sub.add.3 to i64
    747   %arrayidx.4 = getelementptr inbounds i32, i32* %8, i64 %idxprom.4
    748   %15 = load i32, i32* %arrayidx.4, align 4
    749   %cmp1.4 = icmp eq i32 %15, %conv18.i
    750   br i1 %cmp1.4, label %if.then, label %if.end.4
    751 
    752 if.end.4:
    753   %add.4 = add nsw i32 %add.i, %sub.add.3
    754   %cmp4.4 = icmp sgt i32 %add.4, 1050010
    755   %sub.4 = add nsw i32 %add.4, -1050011
    756   %sub.add.4 = select i1 %cmp4.4, i32 %sub.4, i32 %add.4
    757   %idxprom.5 = sext i32 %sub.add.4 to i64
    758   %arrayidx.5 = getelementptr inbounds i32, i32* %8, i64 %idxprom.5
    759   %16 = load i32, i32* %arrayidx.5, align 4
    760   %cmp1.5 = icmp eq i32 %16, %conv18.i
    761   br i1 %cmp1.5, label %if.then, label %if.end.5
    762 
    763 if.end.5:
    764   %add.5 = add nsw i32 %add.i, %sub.add.4
    765   %cmp4.5 = icmp sgt i32 %add.5, 1050010
    766   %sub.5 = add nsw i32 %add.5, -1050011
    767   %sub.add.5 = select i1 %cmp4.5, i32 %sub.5, i32 %add.5
    768   %idxprom.6 = sext i32 %sub.add.5 to i64
    769   %arrayidx.6 = getelementptr inbounds i32, i32* %8, i64 %idxprom.6
    770   %17 = load i32, i32* %arrayidx.6, align 4
    771   %cmp1.6 = icmp eq i32 %17, %conv18.i
    772   br i1 %cmp1.6, label %if.then, label %if.end.6
    773 
    774 if.end.6:
    775   %add.6 = add nsw i32 %add.i, %sub.add.5
    776   %cmp4.6 = icmp sgt i32 %add.6, 1050010
    777   %sub.6 = add nsw i32 %add.6, -1050011
    778   %sub.add.6 = select i1 %cmp4.6, i32 %sub.6, i32 %add.6
    779   %idxprom.7 = sext i32 %sub.add.6 to i64
    780   %arrayidx.7 = getelementptr inbounds i32, i32* %8, i64 %idxprom.7
    781   %18 = load i32, i32* %arrayidx.7, align 4
    782   %cmp1.7 = icmp eq i32 %18, %conv18.i
    783   br i1 %cmp1.7, label %if.then, label %cleanup
    784 }
    785