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

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; 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
2016-08-23 17:19:22 +08:00
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
2016-08-23 17:19:22 +08:00
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
2016-08-23 17:19:22 +08:00
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
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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
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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}
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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
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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
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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
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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
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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:
;
[Thumb] Teach ISel how to lower compares of AND bitmasks efficiently This is essentially a recommit of r285893, but with a correctness fix. The problem of the original commit was that this: bic r5, r7, #31 cbz r5, .LBB2_10 got rewritten into: lsrs r5, r7, #5 beq .LBB2_10 The result in destination register r5 is not the same and this is incorrect when r5 is not dead. So this fix includes checking the uses of the AND destination register. And also, compared to the original commit, some regression tests didn't need changing anymore because of this extra check. For completeness, this was the original commit message: For the common pattern (CMPZ (AND x, #bitmask), #0), we can do some more efficient instruction selection if the bitmask is one consecutive sequence of set bits (32 - clz(bm) - ctz(bm) == popcount(bm)). 1) If the bitmask touches the LSB, then we can remove all the upper bits and set the flags by doing one LSLS. 2) If the bitmask touches the MSB, then we can remove all the lower bits and set the flags with one LSRS. 3) If the bitmask has popcount == 1 (only one set bit), we can shift that bit into the sign bit with one LSLS and change the condition query from NE/EQ to MI/PL (we could also implement this by shifting into the carry bit and branching on BCC/BCS). 4) Otherwise, we can emit a sequence of LSLS+LSRS to remove the upper and lower zero bits of the mask. 1-3 require only one 16-bit instruction and can elide the CMP. 4 requires two 16-bit instructions but can elide the CMP and doesn't require materializing a complex immediate, so is also a win. Differential Revision: https://reviews.llvm.org/D27761 llvm-svn: 289794
2016-12-15 17:38:59 +08:00
; ENABLE: {{tst r2, #1|lsls r1, r2, #31}}
; ENABLE-NEXT: beq [[BB13:LBB[0-9_]+]]
;
; CHECK: push
;
[Thumb] Teach ISel how to lower compares of AND bitmasks efficiently This is essentially a recommit of r285893, but with a correctness fix. The problem of the original commit was that this: bic r5, r7, #31 cbz r5, .LBB2_10 got rewritten into: lsrs r5, r7, #5 beq .LBB2_10 The result in destination register r5 is not the same and this is incorrect when r5 is not dead. So this fix includes checking the uses of the AND destination register. And also, compared to the original commit, some regression tests didn't need changing anymore because of this extra check. For completeness, this was the original commit message: For the common pattern (CMPZ (AND x, #bitmask), #0), we can do some more efficient instruction selection if the bitmask is one consecutive sequence of set bits (32 - clz(bm) - ctz(bm) == popcount(bm)). 1) If the bitmask touches the LSB, then we can remove all the upper bits and set the flags by doing one LSLS. 2) If the bitmask touches the MSB, then we can remove all the lower bits and set the flags with one LSRS. 3) If the bitmask has popcount == 1 (only one set bit), we can shift that bit into the sign bit with one LSLS and change the condition query from NE/EQ to MI/PL (we could also implement this by shifting into the carry bit and branching on BCC/BCS). 4) Otherwise, we can emit a sequence of LSLS+LSRS to remove the upper and lower zero bits of the mask. 1-3 require only one 16-bit instruction and can elide the CMP. 4 requires two 16-bit instructions but can elide the CMP and doesn't require materializing a complex immediate, so is also a win. Differential Revision: https://reviews.llvm.org/D27761 llvm-svn: 289794
2016-12-15 17:38:59 +08:00
; 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
;
; FIXME: This is flakey passing by finding 'bl' somewhere amongst the debug
; info (like labels named 'line_table) not because it's found a bl instruction.
;
; CHECK: bl
2016-08-23 17:19:22 +08:00
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: !4, globals: !2, imports: !2)
!1 = !DIFile(filename: "a.cpp", directory: "b")
!2 = !{}
!3 = !{i32 2, !"Debug Info Version", i32 3}
!4 = !{!5}
!5 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)