llvm-6502/test/CodeGen/Thumb2/2010-08-10-VarSizedAllocaBug.ll
Evan Cheng ac096808a3 Re-apply r110655 with fixes. Epilogue must restore sp from fp if the function stack frame has a var-sized object.
Also added a test case to check for the added benefit of this patch: it's optimizing away the unnecessary restore of sp from fp for some non-leaf functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110707 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-10 19:30:19 +00:00

54 lines
2.0 KiB
LLVM

; RUN: llc < %s -mtriple=thumbv7-apple-darwin -mcpu=cortex-a8 -O3 | FileCheck %s
@.str = private constant [4 x i8] c"%d\0A\00", align 4 ; <[4 x i8]*> [#uses=1]
define internal fastcc i32 @Callee(i32 %i) nounwind {
entry:
; CHECK: Callee:
%0 = icmp eq i32 %i, 0 ; <i1> [#uses=1]
br i1 %0, label %bb2, label %bb
bb: ; preds = %entry
%1 = alloca [1000 x i8], align 4 ; <[1000 x i8]*> [#uses=1]
%.sub = getelementptr inbounds [1000 x i8]* %1, i32 0, i32 0 ; <i8*> [#uses=2]
%2 = call i32 (i8*, i32, i32, i8*, ...)* @__sprintf_chk(i8* %.sub, i32 0, i32 1000, i8* getelementptr inbounds ([4 x i8]* @.str, i32 0, i32 0), i32 %i) nounwind ; <i32> [#uses=0]
%3 = load i8* %.sub, align 4 ; <i8> [#uses=1]
%4 = sext i8 %3 to i32 ; <i32> [#uses=1]
ret i32 %4
bb2: ; preds = %entry
; Must restore sp from fp here
; CHECK: mov sp, r7
; CHECK: sub sp, #8
; CHECK: pop
ret i32 0
}
declare i32 @__sprintf_chk(i8*, i32, i32, i8*, ...) nounwind
define i32 @main() nounwind {
; CHECK: main:
bb.nph:
br label %bb
bb: ; preds = %bb, %bb.nph
%0 = phi i32 [ 0, %bb.nph ], [ %3, %bb ] ; <i32> [#uses=2]
%j.01 = phi i32 [ 0, %bb.nph ], [ %2, %bb ] ; <i32> [#uses=1]
%1 = tail call fastcc i32 @Callee(i32 %0) nounwind ; <i32> [#uses=1]
%2 = add nsw i32 %1, %j.01 ; <i32> [#uses=2]
%3 = add nsw i32 %0, 1 ; <i32> [#uses=2]
%exitcond = icmp eq i32 %3, 10000 ; <i1> [#uses=1]
br i1 %exitcond, label %bb2, label %bb
bb2: ; preds = %bb
; No need to restore sp from fp here.
; CHECK: printf
; CHECK-NOT: mov sp, r7
; CHECK-NOT: sub sp, #12
; CHECK: pop
%4 = tail call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([4 x i8]* @.str, i32 0, i32 0), i32 %2) nounwind ; <i32> [#uses=0]
ret i32 0
}
declare i32 @printf(i8* nocapture, ...) nounwind