175 lines
5.3 KiB
LLVM
175 lines
5.3 KiB
LLVM
; RUN: opt < %s -tailcallelim -verify-dom-info -S | FileCheck %s
|
|
; PR4323
|
|
|
|
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
|
|
|
|
; Several cases where tail call elimination should move the load above the call,
|
|
; then eliminate the tail recursion.
|
|
|
|
|
|
|
|
@global = external global i32 ; <i32*> [#uses=1]
|
|
@extern_weak_global = extern_weak global i32 ; <i32*> [#uses=1]
|
|
|
|
|
|
; This load can be moved above the call because the function won't write to it
|
|
; and the call has no side effects.
|
|
define fastcc i32 @raise_load_1(i32* %a_arg, i32 %a_len_arg, i32 %start_arg) nounwind readonly {
|
|
; CHECK-LABEL: @raise_load_1(
|
|
; CHECK-NOT: call
|
|
; CHECK: load i32, i32*
|
|
; CHECK-NOT: call
|
|
; CHECK: }
|
|
entry:
|
|
%tmp2 = icmp sge i32 %start_arg, %a_len_arg ; <i1> [#uses=1]
|
|
br i1 %tmp2, label %if, label %else
|
|
|
|
if: ; preds = %entry
|
|
ret i32 0
|
|
|
|
else: ; preds = %entry
|
|
%tmp7 = add i32 %start_arg, 1 ; <i32> [#uses=1]
|
|
%tmp8 = call fastcc i32 @raise_load_1(i32* %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
|
|
%tmp9 = load i32, i32* %a_arg ; <i32> [#uses=1]
|
|
%tmp10 = add i32 %tmp9, %tmp8 ; <i32> [#uses=1]
|
|
ret i32 %tmp10
|
|
}
|
|
|
|
|
|
; This load can be moved above the call because the function won't write to it
|
|
; and the load provably can't trap.
|
|
define fastcc i32 @raise_load_2(i32* %a_arg, i32 %a_len_arg, i32 %start_arg) readonly {
|
|
; CHECK-LABEL: @raise_load_2(
|
|
; CHECK-NOT: call
|
|
; CHECK: load i32, i32*
|
|
; CHECK-NOT: call
|
|
; CHECK: }
|
|
entry:
|
|
%tmp2 = icmp sge i32 %start_arg, %a_len_arg ; <i1> [#uses=1]
|
|
br i1 %tmp2, label %if, label %else
|
|
|
|
if: ; preds = %entry
|
|
ret i32 0
|
|
|
|
else: ; preds = %entry
|
|
%nullcheck = icmp eq i32* %a_arg, null ; <i1> [#uses=1]
|
|
br i1 %nullcheck, label %unwind, label %recurse
|
|
|
|
unwind: ; preds = %else
|
|
unreachable
|
|
|
|
recurse: ; preds = %else
|
|
%tmp7 = add i32 %start_arg, 1 ; <i32> [#uses=1]
|
|
%tmp8 = call fastcc i32 @raise_load_2(i32* %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
|
|
%tmp9 = load i32, i32* @global ; <i32> [#uses=1]
|
|
%tmp10 = add i32 %tmp9, %tmp8 ; <i32> [#uses=1]
|
|
ret i32 %tmp10
|
|
}
|
|
|
|
|
|
; This load can be safely moved above the call (even though it's from an
|
|
; extern_weak global) because the call has no side effects.
|
|
define fastcc i32 @raise_load_3(i32* %a_arg, i32 %a_len_arg, i32 %start_arg) nounwind readonly {
|
|
; CHECK-LABEL: @raise_load_3(
|
|
; CHECK-NOT: call
|
|
; CHECK: load i32, i32*
|
|
; CHECK-NOT: call
|
|
; CHECK: }
|
|
entry:
|
|
%tmp2 = icmp sge i32 %start_arg, %a_len_arg ; <i1> [#uses=1]
|
|
br i1 %tmp2, label %if, label %else
|
|
|
|
if: ; preds = %entry
|
|
ret i32 0
|
|
|
|
else: ; preds = %entry
|
|
%tmp7 = add i32 %start_arg, 1 ; <i32> [#uses=1]
|
|
%tmp8 = call fastcc i32 @raise_load_3(i32* %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
|
|
%tmp9 = load i32, i32* @extern_weak_global ; <i32> [#uses=1]
|
|
%tmp10 = add i32 %tmp9, %tmp8 ; <i32> [#uses=1]
|
|
ret i32 %tmp10
|
|
}
|
|
|
|
|
|
; The second load can be safely moved above the call even though it's from an
|
|
; unknown pointer (which normally means it might trap) because the first load
|
|
; proves it doesn't trap.
|
|
define fastcc i32 @raise_load_4(i32* %a_arg, i32 %a_len_arg, i32 %start_arg) readonly {
|
|
; CHECK-LABEL: @raise_load_4(
|
|
; CHECK-NOT: call
|
|
; CHECK: load i32, i32*
|
|
; CHECK-NEXT: load i32, i32*
|
|
; CHECK-NOT: call
|
|
; CHECK: }
|
|
entry:
|
|
%tmp2 = icmp sge i32 %start_arg, %a_len_arg ; <i1> [#uses=1]
|
|
br i1 %tmp2, label %if, label %else
|
|
|
|
if: ; preds = %entry
|
|
ret i32 0
|
|
|
|
else: ; preds = %entry
|
|
%nullcheck = icmp eq i32* %a_arg, null ; <i1> [#uses=1]
|
|
br i1 %nullcheck, label %unwind, label %recurse
|
|
|
|
unwind: ; preds = %else
|
|
unreachable
|
|
|
|
recurse: ; preds = %else
|
|
%tmp7 = add i32 %start_arg, 1 ; <i32> [#uses=1]
|
|
%first = load i32, i32* %a_arg ; <i32> [#uses=1]
|
|
%tmp8 = call fastcc i32 @raise_load_4(i32* %a_arg, i32 %first, i32 %tmp7) ; <i32> [#uses=1]
|
|
%second = load i32, i32* %a_arg ; <i32> [#uses=1]
|
|
%tmp10 = add i32 %second, %tmp8 ; <i32> [#uses=1]
|
|
ret i32 %tmp10
|
|
}
|
|
|
|
; This load can be moved above the call because the function won't write to it
|
|
; and the a_arg is dereferenceable.
|
|
define fastcc i32 @raise_load_5(i32* dereferenceable(4) align 4 %a_arg, i32 %a_len_arg, i32 %start_arg) readonly {
|
|
; CHECK-LABEL: @raise_load_5(
|
|
; CHECK-NOT: call
|
|
; CHECK: load i32, i32*
|
|
; CHECK-NOT: call
|
|
; CHECK: }
|
|
entry:
|
|
%tmp2 = icmp sge i32 %start_arg, %a_len_arg ; <i1> [#uses=1]
|
|
br i1 %tmp2, label %if, label %else
|
|
|
|
if: ; preds = %entry
|
|
ret i32 0
|
|
|
|
else: ; preds = %entry
|
|
%tmp7 = add i32 %start_arg, 1 ; <i32> [#uses=1]
|
|
%tmp8 = call fastcc i32 @raise_load_5(i32* %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
|
|
%tmp9 = load i32, i32* %a_arg ; <i32> [#uses=1]
|
|
%tmp10 = add i32 %tmp9, %tmp8 ; <i32> [#uses=1]
|
|
ret i32 %tmp10
|
|
}
|
|
|
|
; This load can be moved above the call because the function call does not write to the memory the load
|
|
; is accessing and the load is safe to speculate.
|
|
define fastcc i32 @raise_load_6(i32* %a_arg, i32 %a_len_arg, i32 %start_arg) nounwind {
|
|
; CHECK-LABEL: @raise_load_6(
|
|
; CHECK-NOT: call
|
|
; CHECK: load i32, i32*
|
|
; CHECK-NOT: call
|
|
; CHECK: }
|
|
entry:
|
|
%s = alloca i32
|
|
store i32 4, i32* %s
|
|
%tmp2 = icmp sge i32 %start_arg, %a_len_arg ; <i1> [#uses=1]
|
|
br i1 %tmp2, label %if, label %else
|
|
|
|
if: ; preds = %entry
|
|
store i32 1, i32* %a_arg
|
|
ret i32 0
|
|
|
|
else: ; preds = %entry
|
|
%tmp7 = add i32 %start_arg, 1 ; <i32> [#uses=1]
|
|
%tmp8 = call fastcc i32 @raise_load_6(i32* %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
|
|
%tmp9 = load i32, i32* %s ; <i32> [#uses=1]
|
|
%tmp10 = add i32 %tmp9, %tmp8 ; <i32> [#uses=1]
|
|
ret i32 %tmp10
|
|
}
|