vargs.ll
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; RUN: llc -mtriple=thumb-eabi %s -o /dev/null
; RUN: llc -mtriple=thumb-linux %s -o - | FileCheck %s
; RUN: llc -mtriple=thumb-darwin %s -o - | FileCheck %s
@str = internal constant [4 x i8] c"%d\0A\00" ; <[4 x i8]*> [#uses=1]
define void @f(i32 %a, ...) {
entry:
; Check that space is reserved above the pushed lr for variadic argument
; registers to be stored in.
; CHECK: sub sp, #[[IMM:[0-9]+]]
; CHECK: push
%va = alloca i8*, align 4 ; <i8**> [#uses=4]
%va.upgrd.1 = bitcast i8** %va to i8* ; <i8*> [#uses=1]
call void @llvm.va_start( i8* %va.upgrd.1 )
br label %bb
bb: ; preds = %bb, %entry
%a_addr.0 = phi i32 [ %a, %entry ], [ %tmp5, %bb ] ; <i32> [#uses=2]
%tmp = load volatile i8*, i8** %va ; <i8*> [#uses=2]
%tmp2 = getelementptr i8, i8* %tmp, i32 4 ; <i8*> [#uses=1]
store volatile i8* %tmp2, i8** %va
%tmp5 = add i32 %a_addr.0, -1 ; <i32> [#uses=1]
%tmp.upgrd.2 = icmp eq i32 %a_addr.0, 1 ; <i1> [#uses=1]
br i1 %tmp.upgrd.2, label %bb7, label %bb
bb7: ; preds = %bb
%tmp3 = bitcast i8* %tmp to i32* ; <i32*> [#uses=1]
%tmp.upgrd.3 = load i32, i32* %tmp3 ; <i32> [#uses=1]
%tmp10 = call i32 (i8*, ...) @printf( i8* getelementptr ([4 x i8], [4 x i8]* @str, i32 0, i64 0), i32 %tmp.upgrd.3 ) ; <i32> [#uses=0]
%va.upgrd.4 = bitcast i8** %va to i8* ; <i8*> [#uses=1]
call void @llvm.va_end( i8* %va.upgrd.4 )
ret void
; The return sequence should pop the lr to r0-3, recover the stack space used to
; store variadic argument registers, then return via r3. Possibly there is a pop
; before this, but only if the function happened to use callee-saved registers.
; CHECK: pop {[[POP_REG:r[0-3]]]}
; CHECK: add sp, #[[IMM]]
; CHECK: bx [[POP_REG]]
}
declare void @llvm.va_start(i8*)
declare i32 @printf(i8*, ...)
declare void @llvm.va_end(i8*)