llvm/test/CodeGen/ARM/arm-shrink-wrapping.ll - toolchain/llvm-project - Gitiles

 ; RUN: llc %s -o - -enable-shrink-wrap=true -ifcvt-fn-start=1 -ifcvt-fn-stop=0 -mtriple=armv7-apple-ios \
 ; RUN:      | FileCheck %s --check-prefix=CHECK --check-prefix=ARM --check-prefix=ENABLE --check-prefix=ARM-ENABLE
 ; RUN: llc %s -o - -enable-shrink-wrap=false -ifcvt-fn-start=1 -ifcvt-fn-stop=0 -mtriple=armv7-apple-ios \
 ; RUN:      | FileCheck %s --check-prefix=CHECK --check-prefix=ARM --check-prefix=DISABLE --check-prefix=ARM-DISABLE
 ; RUN: llc %s -o - -enable-shrink-wrap=true -ifcvt-fn-start=1 -ifcvt-fn-stop=0 -mtriple=thumbv7-apple-ios \
 ; RUN:      | FileCheck %s --check-prefix=CHECK --check-prefix=THUMB --check-prefix=ENABLE --check-prefix=THUMB-ENABLE
 ; RUN: llc %s -o - -enable-shrink-wrap=false -ifcvt-fn-start=1 -ifcvt-fn-stop=0 -mtriple=thumbv7-apple-ios \
 ; RUN:      | FileCheck %s --check-prefix=CHECK --check-prefix=THUMB --check-prefix=DISABLE --check-prefix=THUMB-DISABLE

 ;
 ; Note: Lots of tests use inline asm instead of regular calls.
 ; This allows to have a better control on what the allocation will do.
 ; Otherwise, we may have spill right in the entry block, defeating
 ; shrink-wrapping. Moreover, some of the inline asm statements (nop)
 ; are here to ensure that the related paths do not end up as critical
 ; edges.
 ; Also disable the late if-converter as it makes harder to reason on
 ; the diffs.

 ; Initial motivating example: Simple diamond with a call just on one side.
 ; CHECK-LABEL: foo:
 ;
 ; Compare the arguments and jump to exit.
 ; No prologue needed.
 ; ENABLE: cmp r0, r1
 ; ENABLE-NEXT: bge [[EXIT_LABEL:LBB[0-9_]+]]
 ;
 ; Prologue code.
 ; CHECK: push {r7, lr}
 ; CHECK-NEXT: mov r7, sp
 ;;
 ; Compare the arguments and jump to exit.
 ; After the prologue is set.
 ; DISABLE: sub sp
 ; DISABLE: cmp r0, r1
 ; DISABLE-NEXT: bge [[EXIT_LABEL:LBB[0-9_]+]]
 ;
 ; Store %a in the alloca.
 ; ARM-ENABLE: push {r0}
 ; THUMB-ENABLE: str r0, [sp, #-4]
 ; DISABLE: str r0, [sp]
 ; Set the alloca address in the second argument.
 ; CHECK-NEXT: mov r1, sp
 ; Set the first argument to zero.
 ; CHECK-NEXT: mov{{s?}} r0, #0
 ; CHECK-NEXT: bl{{x?}} _doSomething
 ;
 ; With shrink-wrapping, epilogue is just after the call.
 ; ARM-ENABLE-NEXT: mov sp, r7
 ; THUMB-ENABLE-NEXT: add sp, #4
 ; ENABLE-NEXT: pop{{(\.w)?}} {r7, lr}
 ;
 ; CHECK: [[EXIT_LABEL]]:
 ;
 ; Without shrink-wrapping, epilogue is in the exit block.
 ; Epilogue code. (What we pop does not matter.)
 ; ARM-DISABLE: mov sp, r7
 ; THUMB-DISABLE: add sp,
 ; DISABLE-NEXT: pop {r7, pc}
 ;
 ; ENABLE-NEXT: bx lr
 define i32 @foo(i32 %a, i32 %b) "no-frame-pointer-elim"="true" {
   %tmp = alloca i32, align 4
   %tmp2 = icmp slt i32 %a, %b
   br i1 %tmp2, label %true, label %false

 true:
   store i32 %a, i32* %tmp, align 4
   %tmp4 = call i32 @doSomething(i32 0, i32* %tmp)
   br label %false

 false:
   %tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %0 ]
   ret i32 %tmp.0
 }

 ; Function Attrs: optsize
 declare i32 @doSomething(i32, i32*)


 ; Check that we do not perform the restore inside the loop whereas the save
 ; is outside.
 ; CHECK-LABEL: freqSaveAndRestoreOutsideLoop:
 ;
 ; Shrink-wrapping allows to skip the prologue in the else case.
 ; ARM-ENABLE: cmp r0, #0
 ; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; Prologue code.
 ; Make sure we save the CSR used in the inline asm: r4.
 ; CHECK: push {r4, r7, lr}
 ; CHECK-NEXT: add r7, sp, #4
 ;
 ; ARM-DISABLE: cmp r0, #0
 ; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-DISABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; SUM is in r0 because it is coalesced with the second
 ; argument on the else path.
 ; CHECK: mov{{s?}} [[SUM:r0]], #0
 ; CHECK-NEXT: mov{{s?}} [[IV:r[0-9]+]], #10
 ;
 ; Next BB.
 ; CHECK: [[LOOP:LBB[0-9_]+]]: @ %for.body
 ; CHECK: mov{{(\.w)?}} [[TMP:r[0-9]+]], #1
 ; ARM: subs [[IV]], [[IV]], #1
 ; THUMB: subs [[IV]], #1
 ; ARM-NEXT: add [[SUM]], [[TMP]], [[SUM]]
 ; THUMB-NEXT: add [[SUM]], [[TMP]]
 ; CHECK-NEXT: bne [[LOOP]]
 ;
 ; Next BB.
 ; SUM << 3.
 ; CHECK: lsl{{s?}} [[SUM]], [[SUM]], #3
 ; ENABLE-NEXT: pop {r4, r7, pc}
 ;
 ; Duplicated epilogue.
 ; DISABLE: pop {r4, r7, pc}
 ;
 ; CHECK: [[ELSE_LABEL]]: @ %if.else
 ; Shift second argument by one and store into returned register.
 ; CHECK: lsl{{s?}} r0, r1, #1
 ; DISABLE-NEXT: pop {r4, r7, pc}
 ;
 ; ENABLE-NEXT: bx lr
 define i32 @freqSaveAndRestoreOutsideLoop(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" {
 entry:
   %tobool = icmp eq i32 %cond, 0
   br i1 %tobool, label %if.else, label %for.preheader

 for.preheader:
   tail call void asm "nop", ""()
   br label %for.body

 for.body:                                         ; preds = %entry, %for.body
   %i.05 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
   %sum.04 = phi i32 [ %add, %for.body ], [ 0, %for.preheader ]
   %call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
   %add = add nsw i32 %call, %sum.04
   %inc = add nuw nsw i32 %i.05, 1
   %exitcond = icmp eq i32 %inc, 10
   br i1 %exitcond, label %for.end, label %for.body

 for.end:                                          ; preds = %for.body
   %shl = shl i32 %add, 3
   br label %if.end

 if.else:                                          ; preds = %entry
   %mul = shl nsw i32 %N, 1
   br label %if.end

 if.end:                                           ; preds = %if.else, %for.end
   %sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
   ret i32 %sum.1
 }

 declare i32 @something(...)

 ; Check that we do not perform the shrink-wrapping inside the loop even
 ; though that would be legal. The cost model must prevent that.
 ; CHECK-LABEL: freqSaveAndRestoreOutsideLoop2:
 ; Prologue code.
 ; Make sure we save the CSR used in the inline asm: r4.
 ; CHECK: push {r4
 ; CHECK: mov{{s?}} [[SUM:r0]], #0
 ; CHECK-NEXT: mov{{s?}} [[IV:r[0-9]+]], #10
 ; CHECK: nop
 ; Next BB.
 ; CHECK: [[LOOP_LABEL:LBB[0-9_]+]]: @ %for.body
 ; CHECK: mov{{(\.w)?}} [[TMP:r[0-9]+]], #1
 ; ARM: subs [[IV]], [[IV]], #1
 ; THUMB: subs [[IV]], #1
 ; ARM: add [[SUM]], [[TMP]], [[SUM]]
 ; THUMB: add [[SUM]], [[TMP]]
 ; CHECK-NEXT: bne [[LOOP_LABEL]]
 ; Next BB.
 ; CHECK: @ %for.exit
 ; CHECK: nop
 ; CHECK: pop {r4
 define i32 @freqSaveAndRestoreOutsideLoop2(i32 %cond) "no-frame-pointer-elim"="true" {
 entry:
   br label %for.preheader

 for.preheader:
   tail call void asm "nop", ""()
   br label %for.body

 for.body:                                         ; preds = %for.body, %entry
   %i.04 = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]
   %sum.03 = phi i32 [ 0, %for.preheader ], [ %add, %for.body ]
   %call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
   %add = add nsw i32 %call, %sum.03
   %inc = add nuw nsw i32 %i.04, 1
   %exitcond = icmp eq i32 %inc, 10
   br i1 %exitcond, label %for.exit, label %for.body

 for.exit:
   tail call void asm "nop", ""()
   br label %for.end

 for.end:                                          ; preds = %for.body
   ret i32 %add
 }

 ; Check with a more complex case that we do not have save within the loop and
 ; restore outside.
 ; CHECK-LABEL: loopInfoSaveOutsideLoop:
 ;
 ; ARM-ENABLE: cmp r0, #0
 ; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; Prologue code.
 ; Make sure we save the CSR used in the inline asm: r4.
 ; CHECK: push {r4, r7, lr}
 ; CHECK-NEXT: add r7, sp, #4
 ;
 ; ARM-DISABLE: cmp r0, #0
 ; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-DISABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; SUM is in r0 because it is coalesced with the second
 ; argument on the else path.
 ; CHECK: mov{{s?}} [[SUM:r0]], #0
 ; CHECK-NEXT: mov{{s?}} [[IV:r[0-9]+]], #10
 ;
 ; Next BB.
 ; CHECK: [[LOOP:LBB[0-9_]+]]: @ %for.body
 ; CHECK: mov{{(\.w)?}} [[TMP:r[0-9]+]], #1
 ; ARM: subs [[IV]], [[IV]], #1
 ; THUMB: subs [[IV]], #1
 ; ARM-NEXT: add [[SUM]], [[TMP]], [[SUM]]
 ; THUMB-NEXT: add [[SUM]], [[TMP]]
 ; CHECK-NEXT: bne [[LOOP]]
 ;
 ; Next BB.
 ; SUM << 3.
 ; CHECK: lsl{{s?}} [[SUM]], [[SUM]], #3
 ; ENABLE: pop {r4, r7, pc}
 ;
 ; Duplicated epilogue.
 ; DISABLE: pop {r4, r7, pc}
 ;
 ; CHECK: [[ELSE_LABEL]]: @ %if.else
 ; Shift second argument by one and store into returned register.
 ; CHECK: lsl{{s?}} r0, r1, #1
 ; DISABLE-NEXT: pop {r4, r7, pc}
 ;
 ; ENABLE-NEXT: bx lr
 define i32 @loopInfoSaveOutsideLoop(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" {
 entry:
   %tobool = icmp eq i32 %cond, 0
   br i1 %tobool, label %if.else, label %for.preheader

 for.preheader:
   tail call void asm "nop", ""()
   br label %for.body

 for.body:                                         ; preds = %entry, %for.body
   %i.05 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
   %sum.04 = phi i32 [ %add, %for.body ], [ 0, %for.preheader ]
   %call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
   %add = add nsw i32 %call, %sum.04
   %inc = add nuw nsw i32 %i.05, 1
   %exitcond = icmp eq i32 %inc, 10
   br i1 %exitcond, label %for.end, label %for.body

 for.end:                                          ; preds = %for.body
   tail call void asm "nop", "~{r4}"()
   %shl = shl i32 %add, 3
   br label %if.end

 if.else:                                          ; preds = %entry
   %mul = shl nsw i32 %N, 1
   br label %if.end

 if.end:                                           ; preds = %if.else, %for.end
   %sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
   ret i32 %sum.1
 }

 declare void @somethingElse(...)

 ; Check with a more complex case that we do not have restore within the loop and
 ; save outside.
 ; CHECK-LABEL: loopInfoRestoreOutsideLoop:
 ;
 ; ARM-ENABLE: cmp r0, #0
 ; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; Prologue code.
 ; Make sure we save the CSR used in the inline asm: r4.
 ; CHECK: push {r4, r7, lr}
 ; CHECK-NEXT: add r7, sp, #4
 ;
 ; ARM-DISABLE: cmp r0, #0
 ; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-DISABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; SUM is in r0 because it is coalesced with the second
 ; argument on the else path.
 ; CHECK: mov{{s?}} [[SUM:r0]], #0
 ; CHECK-NEXT: mov{{s?}} [[IV:r[0-9]+]], #10
 ;
 ; Next BB.
 ; CHECK: [[LOOP:LBB[0-9_]+]]: @ %for.body
 ; CHECK: mov{{(\.w)?}} [[TMP:r[0-9]+]], #1
 ; ARM: subs [[IV]], [[IV]], #1
 ; THUMB: subs [[IV]], #1
 ; ARM-NEXT: add [[SUM]], [[TMP]], [[SUM]]
 ; THUMB-NEXT: add [[SUM]], [[TMP]]
 ; CHECK-NEXT: bne [[LOOP]]
 ;
 ; Next BB.
 ; SUM << 3.
 ; CHECK: lsl{{s?}} [[SUM]], [[SUM]], #3
 ; ENABLE-NEXT: pop {r4, r7, pc}
 ;
 ; Duplicated epilogue.
 ; DISABLE: pop {r4, r7, pc}
 ;
 ; CHECK: [[ELSE_LABEL]]: @ %if.else
 ; Shift second argument by one and store into returned register.
 ; CHECK: lsl{{s?}} r0, r1, #1
 ; DISABLE-NEXT: pop {r4, r7, pc}
 ;
 ; ENABLE-NEXT: bx lr
 define i32 @loopInfoRestoreOutsideLoop(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" #0 {
 entry:
   %tobool = icmp eq i32 %cond, 0
   br i1 %tobool, label %if.else, label %if.then

 if.then:                                          ; preds = %entry
   tail call void asm "nop", "~{r4}"()
   br label %for.body

 for.body:                                         ; preds = %for.body, %if.then
   %i.05 = phi i32 [ 0, %if.then ], [ %inc, %for.body ]
   %sum.04 = phi i32 [ 0, %if.then ], [ %add, %for.body ]
   %call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
   %add = add nsw i32 %call, %sum.04
   %inc = add nuw nsw i32 %i.05, 1
   %exitcond = icmp eq i32 %inc, 10
   br i1 %exitcond, label %for.end, label %for.body

 for.end:                                          ; preds = %for.body
   %shl = shl i32 %add, 3
   br label %if.end

 if.else:                                          ; preds = %entry
   %mul = shl nsw i32 %N, 1
   br label %if.end

 if.end:                                           ; preds = %if.else, %for.end
   %sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
   ret i32 %sum.1
 }

 ; Check that we handle function with no frame information correctly.
 ; CHECK-LABEL: emptyFrame:
 ; CHECK: @ %entry
 ; CHECK-NEXT: mov{{s?}} r0, #0
 ; CHECK-NEXT: bx lr
 define i32 @emptyFrame() {
 entry:
   ret i32 0
 }

 ; Check that we handle inline asm correctly.
 ; CHECK-LABEL: inlineAsm:
 ;
 ; ARM-ENABLE: cmp r0, #0
 ; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; Prologue code.
 ; Make sure we save the CSR used in the inline asm: r4.
 ; CHECK: push {r4, r7, lr}
 ; CHECK-NEXT: add r7, sp, #4
 ;
 ; ARM-DISABLE: cmp r0, #0
 ; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-DISABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; CHECK: mov{{s?}} [[IV:r[0-9]+]], #10
 ;
 ; Next BB.
 ; CHECK: [[LOOP:LBB[0-9_]+]]: @ %for.body
 ; ARM: subs [[IV]], [[IV]], #1
 ; THUMB: subs [[IV]], #1
 ; CHECK: add{{(\.w)?}} r4, r4, #1
 ; CHECK: bne [[LOOP]]
 ;
 ; Next BB.
 ; CHECK: mov{{s?}} r0, #0
 ;
 ; Duplicated epilogue.
 ; DISABLE: pop {r4, r7, pc}
 ;
 ; CHECK: [[ELSE_LABEL]]: @ %if.else
 ; Shift second argument by one and store into returned register.
 ; CHECK: lsl{{s?}} r0, r1, #1
 ; DISABLE-NEXT: pop {r4, r7, pc}
 ;
 ; ENABLE-NEXT: bx lr
 define i32 @inlineAsm(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" {
 entry:
   %tobool = icmp eq i32 %cond, 0
   br i1 %tobool, label %if.else, label %for.preheader

 for.preheader:
   tail call void asm "nop", ""()
   br label %for.body

 for.body:                                         ; preds = %entry, %for.body
   %i.03 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
   tail call void asm sideeffect "add r4, #1", "~{r4}"()
   %inc = add nuw nsw i32 %i.03, 1
   %exitcond = icmp eq i32 %inc, 10
   br i1 %exitcond, label %for.exit, label %for.body

 for.exit:
   tail call void asm "nop", ""()
   br label %if.end

 if.else:                                          ; preds = %entry
   %mul = shl nsw i32 %N, 1
   br label %if.end

 if.end:                                           ; preds = %for.body, %if.else
   %sum.0 = phi i32 [ %mul, %if.else ], [ 0, %for.exit ]
   ret i32 %sum.0
 }

 ; Check that we handle calls to variadic functions correctly.
 ; CHECK-LABEL: callVariadicFunc:
 ;
 ; ARM-ENABLE: cmp r0, #0
 ; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; Prologue code.
 ; CHECK: push {r7, lr}
 ; CHECK-NEXT: mov r7, sp
 ; CHECK-NEXT: sub sp, {{(sp, )?}}#12
 ;
 ; ARM-DISABLE: cmp r0, #0
 ; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
 ; THUMB-DISABLE-NEXT: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
 ;
 ; Setup of the varags.
 ; CHECK: mov r0, r1
 ; CHECK-NEXT: mov r2, r1
 ; CHECK-NEXT: mov r3, r1
 ; ARM-NEXT: str r1, [sp]
 ; ARM-NEXT: str r1, [sp, #4]
 ; THUMB-NEXT: strd r1, r1, [sp]
 ; CHECK-NEXT: str r1, [sp, #8]
 ; CHECK-NEXT: bl{{x?}} _someVariadicFunc
 ; CHECK-NEXT: lsl{{s?}} r0, r0, #3
 ; ARM-NEXT: mov sp, r7
 ; THUMB-NEXT: add sp, #12
 ; CHECK-NEXT: pop {r7, pc}
 ;
 ; CHECK: [[ELSE_LABEL]]: @ %if.else
 ; Shift second argument by one and store into returned register.
 ; CHECK: lsl{{s?}} r0, r1, #1
 ;
 ; Epilogue code.
 ; ENABLE-NEXT: bx lr
 ;
 ; ARM-DISABLE-NEXT: mov sp, r7
 ; THUMB-DISABLE-NEXT: add sp, #12
 ; DISABLE-NEXT: pop {r7, pc}
 define i32 @callVariadicFunc(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" {
 entry:
   %tobool = icmp eq i32 %cond, 0
   br i1 %tobool, label %if.else, label %if.then

 if.then:                                          ; preds = %entry
   %call = tail call i32 (i32, ...) @someVariadicFunc(i32 %N, i32 %N, i32 %N, i32 %N, i32 %N, i32 %N, i32 %N)
   %shl = shl i32 %call, 3
   br label %if.end

 if.else:                                          ; preds = %entry
   %mul = shl nsw i32 %N, 1
   br label %if.end

 if.end:                                           ; preds = %if.else, %if.then
   %sum.0 = phi i32 [ %shl, %if.then ], [ %mul, %if.else ]
   ret i32 %sum.0
 }

 declare i32 @someVariadicFunc(i32, ...)

 ; Make sure we do not insert unreachable code after noreturn function.
 ; Although this is not incorrect to insert such code, it is useless
 ; and it hurts the binary size.
 ;
 ; CHECK-LABEL: noreturn:
 ; DISABLE: push
 ; ARM-ENABLE: cmp r0, #0
 ; ARM-DISABLE: cmp r0, #0
 ; ARM-ENABLE: bne [[ABORT:LBB[0-9_]+]]
 ; ARM-DISABLE: bne [[ABORT:LBB[0-9_]+]]
 ; THUMB-ENABLE: cbnz r0,  [[ABORT:LBB[0-9_]+]]
 ; THUMB-DISABLE: cbnz r0,  [[ABORT:LBB[0-9_]+]]

 ;
 ; CHECK: mov{{s?}} r0, #42
 ;
 ; ENABLE-NEXT: bx lr
 ;
 ; DISABLE-NEXT: pop
 ;;
 ; CHECK: [[ABORT]]: @ %if.abort
 ;
 ; ENABLE: push
 ;
 ; CHECK: bl{{x?}} _abort
 ; ENABLE-NOT: pop
 define i32 @noreturn(i8 signext %bad_thing) "no-frame-pointer-elim"="true" {
 entry:
   %tobool = icmp eq i8 %bad_thing, 0
   br i1 %tobool, label %if.end, label %if.abort

 if.abort:
   %call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
   tail call void @abort() #0
   unreachable

 if.end:
   ret i32 42
 }

 declare void @abort() #0

 attributes #0 = { noreturn nounwind }

 ; Make sure that we handle infinite loops properly When checking that the Save
 ; and Restore blocks are control flow equivalent, the loop searches for the
 ; immediate (post) dominator for the (restore) save blocks. When either the Save
 ; or Restore block is located in an infinite loop the only immediate (post)
 ; dominator is itself. In this case, we cannot perform shrink wrapping, but we
 ; should return gracefully and continue compilation.
 ; The only condition for this test is the compilation finishes correctly.
 ; CHECK-LABEL: infiniteloop
 ; CHECK: pop
 define void @infiniteloop() "no-frame-pointer-elim"="true" {
 entry:
   br i1 undef, label %if.then, label %if.end

 if.then:
   %ptr = alloca i32, i32 4
   br label %for.body

 for.body:                                         ; preds = %for.body, %entry
   %sum.03 = phi i32 [ 0, %if.then ], [ %add, %for.body ]
   %call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
   %add = add nsw i32 %call, %sum.03
   store i32 %add, i32* %ptr
   br label %for.body

 if.end:
   ret void
 }

 ; Another infinite loop test this time with a body bigger than just one block.
 ; CHECK-LABEL: infiniteloop2
 ; CHECK: pop
 define void @infiniteloop2() "no-frame-pointer-elim"="true" {
 entry:
   br i1 undef, label %if.then, label %if.end

 if.then:
   %ptr = alloca i32, i32 4
   br label %for.body

 for.body:                                         ; preds = %for.body, %entry
   %sum.03 = phi i32 [ 0, %if.then ], [ %add, %body1 ], [ 1, %body2]
   %call = tail call i32 asm "mov $0, #0", "=r,~{r4}"()
   %add = add nsw i32 %call, %sum.03
   store i32 %add, i32* %ptr
   br i1 undef, label %body1, label %body2

 body1:
   tail call void asm sideeffect "nop", "~{r4}"()
   br label %for.body

 body2:
   tail call void asm sideeffect "nop", "~{r4}"()
   br label %for.body

 if.end:
   ret void
 }

 ; Another infinite loop test this time with two nested infinite loop.
 ; CHECK-LABEL: infiniteloop3
 ; CHECK: bx lr
 define void @infiniteloop3() "no-frame-pointer-elim"="true" {
 entry:
   br i1 undef, label %loop2a, label %body

 body:                                             ; preds = %entry
   br i1 undef, label %loop2a, label %end

 loop1:                                            ; preds = %loop2a, %loop2b
   %var.phi = phi i32* [ %next.phi, %loop2b ], [ %var, %loop2a ]
   %next.phi = phi i32* [ %next.load, %loop2b ], [ %next.var, %loop2a ]
   %0 = icmp eq i32* %var, null
   %next.load = load i32*, i32** undef
   br i1 %0, label %loop2a, label %loop2b

 loop2a:                                           ; preds = %loop1, %body, %entry
   %var = phi i32* [ null, %body ], [ null, %entry ], [ %next.phi, %loop1 ]
   %next.var = phi i32* [ undef, %body ], [ null, %entry ], [ %next.load, %loop1 ]
   br label %loop1

 loop2b:                                           ; preds = %loop1
   %gep1 = bitcast i32* %var.phi to i32*
   %next.ptr = bitcast i32* %gep1 to i32**
   store i32* %next.phi, i32** %next.ptr
   br label %loop1

 end:
   ret void
 }

 ; Function Attrs: nounwind readnone
 declare double @llvm.pow.f64(double, double)

 ; This function needs to spill floating point registers to
 ; exercise the path where we were dereferencing the end iterator
 ; to access debug info location while inserting the spill code
 ; during PEI with shrink-wrapping enable.
 ; CHECK-LABEL: debug_info:
 ;
 ; ENABLE: {{tst  r2, #1|lsls r1, r2, #31}}
 ; ENABLE-NEXT: beq      [[BB13:LBB[0-9_]+]]
 ;
 ; CHECK: push
 ;
 ; DISABLE: {{tst  r2, #1|lsls r1, r2, #31}}
 ; DISABLE: beq      [[BB13:LBB[0-9_]+]]
 ;
 ; CHECK: bl{{x?}} _pow
 ;
 ;
 ; ENABLE: pop
 ;
 ; CHECK: [[BB13]]:
 ; CHECK: vldr
 ;
 ; DISABLE: pop
 ;
 ; CHECK: bl
 define float @debug_info(float %gamma, float %slopeLimit, i1 %or.cond, double %tmp) "no-frame-pointer-elim"="true" {
 bb:
   br i1 %or.cond, label %bb3, label %bb13

 bb3:                                              ; preds = %bb
   %tmp4 = fcmp ogt float %gamma, 1.000000e+00
   %tmp5 = fadd double 1.000000e+00, %tmp
   %tmp6 = select i1 %tmp4, double %tmp5, double %tmp
   %tmp10 = tail call double @llvm.pow.f64(double %tmp, double %tmp)
   %tmp11 = fcmp une double %tmp6, %tmp
   %tmp12 = fadd double %tmp10, %tmp10
   %cutoff.0 = select i1 %tmp11, double %tmp12, double %tmp
   %phitmp = fptrunc double %cutoff.0 to float
   br label %bb13

 bb13:                                             ; preds = %bb3, %bb
   %cutoff.1 = phi float [ 0.000000e+00, %bb ], [ %phitmp, %bb3 ]
   ret float %cutoff.1
 }


 !llvm.dbg.cu = !{!0}
 !llvm.module.flags = !{!3}

 !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "LLVM", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !2, globals: !2, imports: !2)
 !1 = !DIFile(filename: "a.cpp", directory: "b")
 !2 = !{}
 !3 = !{i32 2, !"Debug Info Version", i32 3}
	; RUN: llc %s -o - -enable-shrink-wrap=true -ifcvt-fn-start=1 -ifcvt-fn-stop=0 -mtriple=armv7-apple-ios \
	; RUN: \| FileCheck %s --check-prefix=CHECK --check-prefix=ARM --check-prefix=ENABLE --check-prefix=ARM-ENABLE
	; RUN: llc %s -o - -enable-shrink-wrap=false -ifcvt-fn-start=1 -ifcvt-fn-stop=0 -mtriple=armv7-apple-ios \
	; RUN: \| FileCheck %s --check-prefix=CHECK --check-prefix=ARM --check-prefix=DISABLE --check-prefix=ARM-DISABLE
	; RUN: llc %s -o - -enable-shrink-wrap=true -ifcvt-fn-start=1 -ifcvt-fn-stop=0 -mtriple=thumbv7-apple-ios \
	; RUN: \| FileCheck %s --check-prefix=CHECK --check-prefix=THUMB --check-prefix=ENABLE --check-prefix=THUMB-ENABLE
	; RUN: llc %s -o - -enable-shrink-wrap=false -ifcvt-fn-start=1 -ifcvt-fn-stop=0 -mtriple=thumbv7-apple-ios \
	; RUN: \| FileCheck %s --check-prefix=CHECK --check-prefix=THUMB --check-prefix=DISABLE --check-prefix=THUMB-DISABLE

	;
	; Note: Lots of tests use inline asm instead of regular calls.
	; This allows to have a better control on what the allocation will do.
	; Otherwise, we may have spill right in the entry block, defeating
	; shrink-wrapping. Moreover, some of the inline asm statements (nop)
	; are here to ensure that the related paths do not end up as critical
	; edges.
	; Also disable the late if-converter as it makes harder to reason on
	; the diffs.

	; Initial motivating example: Simple diamond with a call just on one side.
	; CHECK-LABEL: foo:
	;
	; Compare the arguments and jump to exit.
	; No prologue needed.
	; ENABLE: cmp r0, r1
	; ENABLE-NEXT: bge [[EXIT_LABEL:LBB[0-9_]+]]
	;
	; Prologue code.
	; CHECK: push {r7, lr}
	; CHECK-NEXT: mov r7, sp
	;;
	; Compare the arguments and jump to exit.
	; After the prologue is set.
	; DISABLE: sub sp
	; DISABLE: cmp r0, r1
	; DISABLE-NEXT: bge [[EXIT_LABEL:LBB[0-9_]+]]
	;
	; Store %a in the alloca.
	; ARM-ENABLE: push {r0}
	; THUMB-ENABLE: str r0, [sp, #-4]
	; DISABLE: str r0, [sp]
	; Set the alloca address in the second argument.
	; CHECK-NEXT: mov r1, sp
	; Set the first argument to zero.
	; CHECK-NEXT: mov{{s?}} r0, #0
	; CHECK-NEXT: bl{{x?}} _doSomething
	;
	; With shrink-wrapping, epilogue is just after the call.
	; ARM-ENABLE-NEXT: mov sp, r7
	; THUMB-ENABLE-NEXT: add sp, #4
	; ENABLE-NEXT: pop{{(\.w)?}} {r7, lr}
	;
	; CHECK: [[EXIT_LABEL]]:
	;
	; Without shrink-wrapping, epilogue is in the exit block.
	; Epilogue code. (What we pop does not matter.)
	; ARM-DISABLE: mov sp, r7
	; THUMB-DISABLE: add sp,
	; DISABLE-NEXT: pop {r7, pc}
	;
	; ENABLE-NEXT: bx lr
	define i32 @foo(i32 %a, i32 %b) "no-frame-pointer-elim"="true" {
	%tmp = alloca i32, align 4
	%tmp2 = icmp slt i32 %a, %b
	br i1 %tmp2, label %true, label %false

	true:
	store i32 %a, i32* %tmp, align 4
	%tmp4 = call i32 @doSomething(i32 0, i32* %tmp)
	br label %false

	false:
	%tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %0 ]
	ret i32 %tmp.0
	}

	; Function Attrs: optsize
	declare i32 @doSomething(i32, i32*)


	; Check that we do not perform the restore inside the loop whereas the save
	; is outside.
	; CHECK-LABEL: freqSaveAndRestoreOutsideLoop:
	;
	; Shrink-wrapping allows to skip the prologue in the else case.
	; ARM-ENABLE: cmp r0, #0
	; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; Prologue code.
	; Make sure we save the CSR used in the inline asm: r4.
	; CHECK: push {r4, r7, lr}
	; CHECK-NEXT: add r7, sp, #4
	;
	; ARM-DISABLE: cmp r0, #0
	; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-DISABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; SUM is in r0 because it is coalesced with the second
	; argument on the else path.
	; CHECK: mov{{s?}} [[SUM:r0]], #0
	; CHECK-NEXT: mov{{s?}} [[IV:r[0-9]+]], #10
	;
	; Next BB.
	; CHECK: [[LOOP:LBB[0-9_]+]]: @ %for.body
	; CHECK: mov{{(\.w)?}} [[TMP:r[0-9]+]], #1
	; ARM: subs [[IV]], [[IV]], #1
	; THUMB: subs [[IV]], #1
	; ARM-NEXT: add [[SUM]], [[TMP]], [[SUM]]
	; THUMB-NEXT: add [[SUM]], [[TMP]]
	; CHECK-NEXT: bne [[LOOP]]
	;
	; Next BB.
	; SUM << 3.
	; CHECK: lsl{{s?}} [[SUM]], [[SUM]], #3
	; ENABLE-NEXT: pop {r4, r7, pc}
	;
	; Duplicated epilogue.
	; DISABLE: pop {r4, r7, pc}
	;
	; CHECK: [[ELSE_LABEL]]: @ %if.else
	; Shift second argument by one and store into returned register.
	; CHECK: lsl{{s?}} r0, r1, #1
	; DISABLE-NEXT: pop {r4, r7, pc}
	;
	; ENABLE-NEXT: bx lr
	define i32 @freqSaveAndRestoreOutsideLoop(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" {
	entry:
	%tobool = icmp eq i32 %cond, 0
	br i1 %tobool, label %if.else, label %for.preheader

	for.preheader:
	tail call void asm "nop", ""()
	br label %for.body

	for.body: ; preds = %entry, %for.body
	%i.05 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
	%sum.04 = phi i32 [ %add, %for.body ], [ 0, %for.preheader ]
	%call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
	%add = add nsw i32 %call, %sum.04
	%inc = add nuw nsw i32 %i.05, 1
	%exitcond = icmp eq i32 %inc, 10
	br i1 %exitcond, label %for.end, label %for.body

	for.end: ; preds = %for.body
	%shl = shl i32 %add, 3
	br label %if.end

	if.else: ; preds = %entry
	%mul = shl nsw i32 %N, 1
	br label %if.end

	if.end: ; preds = %if.else, %for.end
	%sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
	ret i32 %sum.1
	}

	declare i32 @something(...)

	; Check that we do not perform the shrink-wrapping inside the loop even
	; though that would be legal. The cost model must prevent that.
	; CHECK-LABEL: freqSaveAndRestoreOutsideLoop2:
	; Prologue code.
	; Make sure we save the CSR used in the inline asm: r4.
	; CHECK: push {r4
	; CHECK: mov{{s?}} [[SUM:r0]], #0
	; CHECK-NEXT: mov{{s?}} [[IV:r[0-9]+]], #10
	; CHECK: nop
	; Next BB.
	; CHECK: [[LOOP_LABEL:LBB[0-9_]+]]: @ %for.body
	; CHECK: mov{{(\.w)?}} [[TMP:r[0-9]+]], #1
	; ARM: subs [[IV]], [[IV]], #1
	; THUMB: subs [[IV]], #1
	; ARM: add [[SUM]], [[TMP]], [[SUM]]
	; THUMB: add [[SUM]], [[TMP]]
	; CHECK-NEXT: bne [[LOOP_LABEL]]
	; Next BB.
	; CHECK: @ %for.exit
	; CHECK: nop
	; CHECK: pop {r4
	define i32 @freqSaveAndRestoreOutsideLoop2(i32 %cond) "no-frame-pointer-elim"="true" {
	entry:
	br label %for.preheader

	for.preheader:
	tail call void asm "nop", ""()
	br label %for.body

	for.body: ; preds = %for.body, %entry
	%i.04 = phi i32 [ 0, %for.preheader ], [ %inc, %for.body ]
	%sum.03 = phi i32 [ 0, %for.preheader ], [ %add, %for.body ]
	%call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
	%add = add nsw i32 %call, %sum.03
	%inc = add nuw nsw i32 %i.04, 1
	%exitcond = icmp eq i32 %inc, 10
	br i1 %exitcond, label %for.exit, label %for.body

	for.exit:
	tail call void asm "nop", ""()
	br label %for.end

	for.end: ; preds = %for.body
	ret i32 %add
	}

	; Check with a more complex case that we do not have save within the loop and
	; restore outside.
	; CHECK-LABEL: loopInfoSaveOutsideLoop:
	;
	; ARM-ENABLE: cmp r0, #0
	; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; Prologue code.
	; Make sure we save the CSR used in the inline asm: r4.
	; CHECK: push {r4, r7, lr}
	; CHECK-NEXT: add r7, sp, #4
	;
	; ARM-DISABLE: cmp r0, #0
	; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-DISABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; SUM is in r0 because it is coalesced with the second
	; argument on the else path.
	; CHECK: mov{{s?}} [[SUM:r0]], #0
	; CHECK-NEXT: mov{{s?}} [[IV:r[0-9]+]], #10
	;
	; Next BB.
	; CHECK: [[LOOP:LBB[0-9_]+]]: @ %for.body
	; CHECK: mov{{(\.w)?}} [[TMP:r[0-9]+]], #1
	; ARM: subs [[IV]], [[IV]], #1
	; THUMB: subs [[IV]], #1
	; ARM-NEXT: add [[SUM]], [[TMP]], [[SUM]]
	; THUMB-NEXT: add [[SUM]], [[TMP]]
	; CHECK-NEXT: bne [[LOOP]]
	;
	; Next BB.
	; SUM << 3.
	; CHECK: lsl{{s?}} [[SUM]], [[SUM]], #3
	; ENABLE: pop {r4, r7, pc}
	;
	; Duplicated epilogue.
	; DISABLE: pop {r4, r7, pc}
	;
	; CHECK: [[ELSE_LABEL]]: @ %if.else
	; Shift second argument by one and store into returned register.
	; CHECK: lsl{{s?}} r0, r1, #1
	; DISABLE-NEXT: pop {r4, r7, pc}
	;
	; ENABLE-NEXT: bx lr
	define i32 @loopInfoSaveOutsideLoop(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" {
	entry:
	%tobool = icmp eq i32 %cond, 0
	br i1 %tobool, label %if.else, label %for.preheader

	for.preheader:
	tail call void asm "nop", ""()
	br label %for.body

	for.body: ; preds = %entry, %for.body
	%i.05 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
	%sum.04 = phi i32 [ %add, %for.body ], [ 0, %for.preheader ]
	%call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
	%add = add nsw i32 %call, %sum.04
	%inc = add nuw nsw i32 %i.05, 1
	%exitcond = icmp eq i32 %inc, 10
	br i1 %exitcond, label %for.end, label %for.body

	for.end: ; preds = %for.body
	tail call void asm "nop", "~{r4}"()
	%shl = shl i32 %add, 3
	br label %if.end

	if.else: ; preds = %entry
	%mul = shl nsw i32 %N, 1
	br label %if.end

	if.end: ; preds = %if.else, %for.end
	%sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
	ret i32 %sum.1
	}

	declare void @somethingElse(...)

	; Check with a more complex case that we do not have restore within the loop and
	; save outside.
	; CHECK-LABEL: loopInfoRestoreOutsideLoop:
	;
	; ARM-ENABLE: cmp r0, #0
	; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; Prologue code.
	; Make sure we save the CSR used in the inline asm: r4.
	; CHECK: push {r4, r7, lr}
	; CHECK-NEXT: add r7, sp, #4
	;
	; ARM-DISABLE: cmp r0, #0
	; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-DISABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; SUM is in r0 because it is coalesced with the second
	; argument on the else path.
	; CHECK: mov{{s?}} [[SUM:r0]], #0
	; CHECK-NEXT: mov{{s?}} [[IV:r[0-9]+]], #10
	;
	; Next BB.
	; CHECK: [[LOOP:LBB[0-9_]+]]: @ %for.body
	; CHECK: mov{{(\.w)?}} [[TMP:r[0-9]+]], #1
	; ARM: subs [[IV]], [[IV]], #1
	; THUMB: subs [[IV]], #1
	; ARM-NEXT: add [[SUM]], [[TMP]], [[SUM]]
	; THUMB-NEXT: add [[SUM]], [[TMP]]
	; CHECK-NEXT: bne [[LOOP]]
	;
	; Next BB.
	; SUM << 3.
	; CHECK: lsl{{s?}} [[SUM]], [[SUM]], #3
	; ENABLE-NEXT: pop {r4, r7, pc}
	;
	; Duplicated epilogue.
	; DISABLE: pop {r4, r7, pc}
	;
	; CHECK: [[ELSE_LABEL]]: @ %if.else
	; Shift second argument by one and store into returned register.
	; CHECK: lsl{{s?}} r0, r1, #1
	; DISABLE-NEXT: pop {r4, r7, pc}
	;
	; ENABLE-NEXT: bx lr
	define i32 @loopInfoRestoreOutsideLoop(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" #0 {
	entry:
	%tobool = icmp eq i32 %cond, 0
	br i1 %tobool, label %if.else, label %if.then

	if.then: ; preds = %entry
	tail call void asm "nop", "~{r4}"()
	br label %for.body

	for.body: ; preds = %for.body, %if.then
	%i.05 = phi i32 [ 0, %if.then ], [ %inc, %for.body ]
	%sum.04 = phi i32 [ 0, %if.then ], [ %add, %for.body ]
	%call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
	%add = add nsw i32 %call, %sum.04
	%inc = add nuw nsw i32 %i.05, 1
	%exitcond = icmp eq i32 %inc, 10
	br i1 %exitcond, label %for.end, label %for.body

	for.end: ; preds = %for.body
	%shl = shl i32 %add, 3
	br label %if.end

	if.else: ; preds = %entry
	%mul = shl nsw i32 %N, 1
	br label %if.end

	if.end: ; preds = %if.else, %for.end
	%sum.1 = phi i32 [ %shl, %for.end ], [ %mul, %if.else ]
	ret i32 %sum.1
	}

	; Check that we handle function with no frame information correctly.
	; CHECK-LABEL: emptyFrame:
	; CHECK: @ %entry
	; CHECK-NEXT: mov{{s?}} r0, #0
	; CHECK-NEXT: bx lr
	define i32 @emptyFrame() {
	entry:
	ret i32 0
	}

	; Check that we handle inline asm correctly.
	; CHECK-LABEL: inlineAsm:
	;
	; ARM-ENABLE: cmp r0, #0
	; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; Prologue code.
	; Make sure we save the CSR used in the inline asm: r4.
	; CHECK: push {r4, r7, lr}
	; CHECK-NEXT: add r7, sp, #4
	;
	; ARM-DISABLE: cmp r0, #0
	; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-DISABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; CHECK: mov{{s?}} [[IV:r[0-9]+]], #10
	;
	; Next BB.
	; CHECK: [[LOOP:LBB[0-9_]+]]: @ %for.body
	; ARM: subs [[IV]], [[IV]], #1
	; THUMB: subs [[IV]], #1
	; CHECK: add{{(\.w)?}} r4, r4, #1
	; CHECK: bne [[LOOP]]
	;
	; Next BB.
	; CHECK: mov{{s?}} r0, #0
	;
	; Duplicated epilogue.
	; DISABLE: pop {r4, r7, pc}
	;
	; CHECK: [[ELSE_LABEL]]: @ %if.else
	; Shift second argument by one and store into returned register.
	; CHECK: lsl{{s?}} r0, r1, #1
	; DISABLE-NEXT: pop {r4, r7, pc}
	;
	; ENABLE-NEXT: bx lr
	define i32 @inlineAsm(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" {
	entry:
	%tobool = icmp eq i32 %cond, 0
	br i1 %tobool, label %if.else, label %for.preheader

	for.preheader:
	tail call void asm "nop", ""()
	br label %for.body

	for.body: ; preds = %entry, %for.body
	%i.03 = phi i32 [ %inc, %for.body ], [ 0, %for.preheader ]
	tail call void asm sideeffect "add r4, #1", "~{r4}"()
	%inc = add nuw nsw i32 %i.03, 1
	%exitcond = icmp eq i32 %inc, 10
	br i1 %exitcond, label %for.exit, label %for.body

	for.exit:
	tail call void asm "nop", ""()
	br label %if.end

	if.else: ; preds = %entry
	%mul = shl nsw i32 %N, 1
	br label %if.end

	if.end: ; preds = %for.body, %if.else
	%sum.0 = phi i32 [ %mul, %if.else ], [ 0, %for.exit ]
	ret i32 %sum.0
	}

	; Check that we handle calls to variadic functions correctly.
	; CHECK-LABEL: callVariadicFunc:
	;
	; ARM-ENABLE: cmp r0, #0
	; ARM-ENABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-ENABLE: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; Prologue code.
	; CHECK: push {r7, lr}
	; CHECK-NEXT: mov r7, sp
	; CHECK-NEXT: sub sp, {{(sp, )?}}#12
	;
	; ARM-DISABLE: cmp r0, #0
	; ARM-DISABLE-NEXT: beq [[ELSE_LABEL:LBB[0-9_]+]]
	; THUMB-DISABLE-NEXT: cbz r0, [[ELSE_LABEL:LBB[0-9_]+]]
	;
	; Setup of the varags.
	; CHECK: mov r0, r1
	; CHECK-NEXT: mov r2, r1
	; CHECK-NEXT: mov r3, r1
	; ARM-NEXT: str r1, [sp]
	; ARM-NEXT: str r1, [sp, #4]
	; THUMB-NEXT: strd r1, r1, [sp]
	; CHECK-NEXT: str r1, [sp, #8]
	; CHECK-NEXT: bl{{x?}} _someVariadicFunc
	; CHECK-NEXT: lsl{{s?}} r0, r0, #3
	; ARM-NEXT: mov sp, r7
	; THUMB-NEXT: add sp, #12
	; CHECK-NEXT: pop {r7, pc}
	;
	; CHECK: [[ELSE_LABEL]]: @ %if.else
	; Shift second argument by one and store into returned register.
	; CHECK: lsl{{s?}} r0, r1, #1
	;
	; Epilogue code.
	; ENABLE-NEXT: bx lr
	;
	; ARM-DISABLE-NEXT: mov sp, r7
	; THUMB-DISABLE-NEXT: add sp, #12
	; DISABLE-NEXT: pop {r7, pc}
	define i32 @callVariadicFunc(i32 %cond, i32 %N) "no-frame-pointer-elim"="true" {
	entry:
	%tobool = icmp eq i32 %cond, 0
	br i1 %tobool, label %if.else, label %if.then

	if.then: ; preds = %entry
	%call = tail call i32 (i32, ...) @someVariadicFunc(i32 %N, i32 %N, i32 %N, i32 %N, i32 %N, i32 %N, i32 %N)
	%shl = shl i32 %call, 3
	br label %if.end

	if.else: ; preds = %entry
	%mul = shl nsw i32 %N, 1
	br label %if.end

	if.end: ; preds = %if.else, %if.then
	%sum.0 = phi i32 [ %shl, %if.then ], [ %mul, %if.else ]
	ret i32 %sum.0
	}

	declare i32 @someVariadicFunc(i32, ...)

	; Make sure we do not insert unreachable code after noreturn function.
	; Although this is not incorrect to insert such code, it is useless
	; and it hurts the binary size.
	;
	; CHECK-LABEL: noreturn:
	; DISABLE: push
	; ARM-ENABLE: cmp r0, #0
	; ARM-DISABLE: cmp r0, #0
	; ARM-ENABLE: bne [[ABORT:LBB[0-9_]+]]
	; ARM-DISABLE: bne [[ABORT:LBB[0-9_]+]]
	; THUMB-ENABLE: cbnz r0, [[ABORT:LBB[0-9_]+]]
	; THUMB-DISABLE: cbnz r0, [[ABORT:LBB[0-9_]+]]

	;
	; CHECK: mov{{s?}} r0, #42
	;
	; ENABLE-NEXT: bx lr
	;
	; DISABLE-NEXT: pop
	;;
	; CHECK: [[ABORT]]: @ %if.abort
	;
	; ENABLE: push
	;
	; CHECK: bl{{x?}} _abort
	; ENABLE-NOT: pop
	define i32 @noreturn(i8 signext %bad_thing) "no-frame-pointer-elim"="true" {
	entry:
	%tobool = icmp eq i8 %bad_thing, 0
	br i1 %tobool, label %if.end, label %if.abort

	if.abort:
	%call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
	tail call void @abort() #0
	unreachable

	if.end:
	ret i32 42
	}

	declare void @abort() #0

	attributes #0 = { noreturn nounwind }

	; Make sure that we handle infinite loops properly When checking that the Save
	; and Restore blocks are control flow equivalent, the loop searches for the
	; immediate (post) dominator for the (restore) save blocks. When either the Save
	; or Restore block is located in an infinite loop the only immediate (post)
	; dominator is itself. In this case, we cannot perform shrink wrapping, but we
	; should return gracefully and continue compilation.
	; The only condition for this test is the compilation finishes correctly.
	; CHECK-LABEL: infiniteloop
	; CHECK: pop
	define void @infiniteloop() "no-frame-pointer-elim"="true" {
	entry:
	br i1 undef, label %if.then, label %if.end

	if.then:
	%ptr = alloca i32, i32 4
	br label %for.body

	for.body: ; preds = %for.body, %entry
	%sum.03 = phi i32 [ 0, %if.then ], [ %add, %for.body ]
	%call = tail call i32 asm sideeffect "mov $0, #1", "=r,~{r4}"()
	%add = add nsw i32 %call, %sum.03
	store i32 %add, i32* %ptr
	br label %for.body

	if.end:
	ret void
	}

	; Another infinite loop test this time with a body bigger than just one block.
	; CHECK-LABEL: infiniteloop2
	; CHECK: pop
	define void @infiniteloop2() "no-frame-pointer-elim"="true" {
	entry:
	br i1 undef, label %if.then, label %if.end

	if.then:
	%ptr = alloca i32, i32 4
	br label %for.body

	for.body: ; preds = %for.body, %entry
	%sum.03 = phi i32 [ 0, %if.then ], [ %add, %body1 ], [ 1, %body2]
	%call = tail call i32 asm "mov $0, #0", "=r,~{r4}"()
	%add = add nsw i32 %call, %sum.03
	store i32 %add, i32* %ptr
	br i1 undef, label %body1, label %body2

	body1:
	tail call void asm sideeffect "nop", "~{r4}"()
	br label %for.body

	body2:
	tail call void asm sideeffect "nop", "~{r4}"()
	br label %for.body

	if.end:
	ret void
	}

	; Another infinite loop test this time with two nested infinite loop.
	; CHECK-LABEL: infiniteloop3
	; CHECK: bx lr
	define void @infiniteloop3() "no-frame-pointer-elim"="true" {
	entry:
	br i1 undef, label %loop2a, label %body

	body: ; preds = %entry
	br i1 undef, label %loop2a, label %end

	loop1: ; preds = %loop2a, %loop2b
	%var.phi = phi i32* [ %next.phi, %loop2b ], [ %var, %loop2a ]
	%next.phi = phi i32* [ %next.load, %loop2b ], [ %next.var, %loop2a ]
	%0 = icmp eq i32* %var, null
	%next.load = load i32, i32* undef
	br i1 %0, label %loop2a, label %loop2b

	loop2a: ; preds = %loop1, %body, %entry
	%var = phi i32* [ null, %body ], [ null, %entry ], [ %next.phi, %loop1 ]
	%next.var = phi i32* [ undef, %body ], [ null, %entry ], [ %next.load, %loop1 ]
	br label %loop1

	loop2b: ; preds = %loop1
	%gep1 = bitcast i32* %var.phi to i32*
	%next.ptr = bitcast i32* %gep1 to i32**
	store i32* %next.phi, i32** %next.ptr
	br label %loop1

	end:
	ret void
	}

	; Function Attrs: nounwind readnone
	declare double @llvm.pow.f64(double, double)

	; This function needs to spill floating point registers to
	; exercise the path where we were dereferencing the end iterator
	; to access debug info location while inserting the spill code
	; during PEI with shrink-wrapping enable.
	; CHECK-LABEL: debug_info:
	;
	; ENABLE: {{tst r2, #1\|lsls r1, r2, #31}}
	; ENABLE-NEXT: beq [[BB13:LBB[0-9_]+]]
	;
	; CHECK: push
	;
	; DISABLE: {{tst r2, #1\|lsls r1, r2, #31}}
	; DISABLE: beq [[BB13:LBB[0-9_]+]]
	;
	; CHECK: bl{{x?}} _pow
	;
	;
	; ENABLE: pop
	;
	; CHECK: [[BB13]]:
	; CHECK: vldr
	;
	; DISABLE: pop
	;
	; CHECK: bl
	define float @debug_info(float %gamma, float %slopeLimit, i1 %or.cond, double %tmp) "no-frame-pointer-elim"="true" {
	bb:
	br i1 %or.cond, label %bb3, label %bb13

	bb3: ; preds = %bb
	%tmp4 = fcmp ogt float %gamma, 1.000000e+00
	%tmp5 = fadd double 1.000000e+00, %tmp
	%tmp6 = select i1 %tmp4, double %tmp5, double %tmp
	%tmp10 = tail call double @llvm.pow.f64(double %tmp, double %tmp)
	%tmp11 = fcmp une double %tmp6, %tmp
	%tmp12 = fadd double %tmp10, %tmp10
	%cutoff.0 = select i1 %tmp11, double %tmp12, double %tmp
	%phitmp = fptrunc double %cutoff.0 to float
	br label %bb13

	bb13: ; preds = %bb3, %bb
	%cutoff.1 = phi float [ 0.000000e+00, %bb ], [ %phitmp, %bb3 ]
	ret float %cutoff.1
	}


	!llvm.dbg.cu = !{!0}
	!llvm.module.flags = !{!3}

	!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "LLVM", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !2, globals: !2, imports: !2)
	!1 = !DIFile(filename: "a.cpp", directory: "b")
	!2 = !{}
	!3 = !{i32 2, !"Debug Info Version", i32 3}