llvm-mirror/test/CodeGen/X86/avoid-loop-align.ll
Dan Gohman a72e83c26e [MC] Use .p2align instead of .align
For historic reasons, the behavior of .align differs between targets.
Fortunately, there are alternatives, .p2align and .balign, which make the
interpretation of the parameter explicit, and which behave consistently across
targets.

This patch teaches MC to use .p2align instead of .align, so that people reading
code for multiple architectures don't have to remember which way each platform
does its .align directive.

Differential Revision: http://reviews.llvm.org/D16549

llvm-svn: 258750
2016-01-26 00:03:25 +00:00

40 lines
1.1 KiB
LLVM

; RUN: llc < %s -mtriple=i386-apple-darwin | FileCheck %s
; CodeGen should align the top of the loop, which differs from the loop
; header in this case.
; CHECK: jmp LBB0_2
; CHECK: .p2align
; CHECK: LBB0_1:
@A = common global [100 x i32] zeroinitializer, align 32 ; <[100 x i32]*> [#uses=1]
define i8* @test(i8* %Q, i32* %L) nounwind {
entry:
%tmp = tail call i32 (...) @foo() nounwind ; <i32> [#uses=2]
%tmp1 = inttoptr i32 %tmp to i8* ; <i8*> [#uses=1]
br label %bb1
bb: ; preds = %bb1, %bb1
%indvar.next = add i32 %P.0.rec, 1 ; <i32> [#uses=1]
br label %bb1
bb1: ; preds = %bb, %entry
%P.0.rec = phi i32 [ 0, %entry ], [ %indvar.next, %bb ] ; <i32> [#uses=2]
%P.0 = getelementptr i8, i8* %tmp1, i32 %P.0.rec ; <i8*> [#uses=3]
%tmp2 = load i8, i8* %P.0, align 1 ; <i8> [#uses=1]
switch i8 %tmp2, label %bb4 [
i8 12, label %bb
i8 42, label %bb
]
bb4: ; preds = %bb1
%tmp3 = ptrtoint i8* %P.0 to i32 ; <i32> [#uses=1]
%tmp4 = sub i32 %tmp3, %tmp ; <i32> [#uses=1]
%tmp5 = getelementptr [100 x i32], [100 x i32]* @A, i32 0, i32 %tmp4 ; <i32*> [#uses=1]
store i32 4, i32* %tmp5, align 4
ret i8* %P.0
}
declare i32 @foo(...)