llvm-6502/test/CodeGen/Thumb/dyn-stackalloc.ll
Evan Cheng ab5c703fdb Fix epilogue codegen to avoid leaving the stack pointer in an invalid
state. Previously Thumb2 would restore sp from fp like this:
mov sp, r7
sub, sp, #4
If an interrupt is taken after the 'mov' but before the 'sub', callee-saved
registers might be clobbered by the interrupt handler. Instead, try
restoring directly from sp:
add sp, #4
Or, if necessary (with VLA, etc.) use a scratch register to compute sp and
then restore it:
sub.w r4, r7, #8
mov sp, r7
rdar://8465407


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119977 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-22 18:12:04 +00:00

75 lines
2.1 KiB
LLVM

; RUN: llc < %s -mtriple=thumb-apple-darwin | FileCheck %s
%struct.state = type { i32, %struct.info*, float**, i32, i32, i32, i32, i32, i32, i32, i32, i32, i64, i64, i64, i64, i64, i64, i8* }
%struct.info = type { i32, i32, i32, i32, i32, i32, i32, i8* }
define void @t1(%struct.state* %v) {
; CHECK: t1:
; CHECK: push
; CHECK: add r7, sp, #12
; CHECK: mov r2, sp
; CHECK: subs r4, r2, r1
; CHECK: mov sp, r4
%tmp6 = load i32* null
%tmp8 = alloca float, i32 %tmp6
store i32 1, i32* null
br i1 false, label %bb123.preheader, label %return
bb123.preheader:
br i1 false, label %bb43, label %return
bb43:
call fastcc void @f1( float* %tmp8, float* null, i32 0 )
%tmp70 = load i32* null
%tmp85 = getelementptr float* %tmp8, i32 0
call fastcc void @f2( float* null, float* null, float* %tmp85, i32 %tmp70 )
ret void
return:
ret void
}
declare fastcc void @f1(float*, float*, i32)
declare fastcc void @f2(float*, float*, float*, i32)
%struct.comment = type { i8**, i32*, i32, i8* }
@str215 = external global [2 x i8]
define void @t2(%struct.comment* %vc, i8* %tag, i8* %contents) {
; CHECK: t2:
; CHECK: push
; CHECK: add r7, sp, #12
; CHECK: sub sp, #8
; CHECK: mov r6, sp
; CHECK: str r2, [r6, #4]
; CHECK: str r0, [r6]
; CHECK-NOT: ldr r0, [sp
; CHECK: ldr r0, [r6, #4]
; CHECK: mov r0, sp
; CHECK: subs r5, r0, r1
; CHECK: mov sp, r5
%tmp1 = call i32 @strlen( i8* %tag )
%tmp3 = call i32 @strlen( i8* %contents )
%tmp4 = add i32 %tmp1, 2
%tmp5 = add i32 %tmp4, %tmp3
%tmp6 = alloca i8, i32 %tmp5
%tmp9 = call i8* @strcpy( i8* %tmp6, i8* %tag )
%tmp6.len = call i32 @strlen( i8* %tmp6 )
%tmp6.indexed = getelementptr i8* %tmp6, i32 %tmp6.len
call void @llvm.memcpy.i32( i8* %tmp6.indexed, i8* getelementptr ([2 x i8]* @str215, i32 0, i32 0), i32 2, i32 1 )
%tmp15 = call i8* @strcat( i8* %tmp6, i8* %contents )
call fastcc void @comment_add( %struct.comment* %vc, i8* %tmp6 )
ret void
}
declare i32 @strlen(i8*)
declare i8* @strcat(i8*, i8*)
declare fastcc void @comment_add(%struct.comment*, i8*)
declare void @llvm.memcpy.i32(i8*, i8*, i32, i32)
declare i8* @strcpy(i8*, i8*)