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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=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 ; <ptr> [#uses=1]
@extern_weak_global = extern_weak global i32 ; <ptr> [#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(ptr %a_arg, i32 %a_len_arg, i32 %start_arg) nounwind readonly willreturn {
; CHECK-LABEL: @raise_load_1(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[TAILRECURSE:%.*]]
; CHECK: tailrecurse:
; CHECK-NEXT: [[ACCUMULATOR_TR:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP10:%.*]], [[ELSE:%.*]] ]
; CHECK-NEXT: [[START_ARG_TR:%.*]] = phi i32 [ [[START_ARG:%.*]], [[ENTRY]] ], [ [[TMP7:%.*]], [[ELSE]] ]
; CHECK-NEXT: [[TMP2:%.*]] = icmp sge i32 [[START_ARG_TR]], [[A_LEN_ARG:%.*]]
; CHECK-NEXT: br i1 [[TMP2]], label [[IF:%.*]], label [[ELSE]]
; CHECK: if:
; CHECK-NEXT: [[ACCUMULATOR_RET_TR:%.*]] = add i32 0, [[ACCUMULATOR_TR]]
; CHECK-NEXT: ret i32 [[ACCUMULATOR_RET_TR]]
; CHECK: else:
; CHECK-NEXT: [[TMP7]] = add i32 [[START_ARG_TR]], 1
; CHECK-NEXT: [[TMP9:%.*]] = load i32, ptr [[A_ARG:%.*]], align 4
; CHECK-NEXT: [[TMP10]] = add i32 [[TMP9]], [[ACCUMULATOR_TR]]
; CHECK-NEXT: br label [[TAILRECURSE]]
;
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(ptr %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
%tmp9 = load i32, ptr %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(ptr %a_arg, i32 %a_len_arg, i32 %start_arg) readonly {
; CHECK-LABEL: @raise_load_2(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[TAILRECURSE:%.*]]
; CHECK: tailrecurse:
; CHECK-NEXT: [[ACCUMULATOR_TR:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP10:%.*]], [[RECURSE:%.*]] ]
; CHECK-NEXT: [[START_ARG_TR:%.*]] = phi i32 [ [[START_ARG:%.*]], [[ENTRY]] ], [ [[TMP7:%.*]], [[RECURSE]] ]
; CHECK-NEXT: [[TMP2:%.*]] = icmp sge i32 [[START_ARG_TR]], [[A_LEN_ARG:%.*]]
; CHECK-NEXT: br i1 [[TMP2]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: [[ACCUMULATOR_RET_TR:%.*]] = add i32 0, [[ACCUMULATOR_TR]]
; CHECK-NEXT: ret i32 [[ACCUMULATOR_RET_TR]]
; CHECK: else:
; CHECK-NEXT: [[NULLCHECK:%.*]] = icmp eq ptr [[A_ARG:%.*]], null
; CHECK-NEXT: br i1 [[NULLCHECK]], label [[UNWIND:%.*]], label [[RECURSE]]
; CHECK: unwind:
; CHECK-NEXT: unreachable
; CHECK: recurse:
; CHECK-NEXT: [[TMP7]] = add i32 [[START_ARG_TR]], 1
; CHECK-NEXT: [[TMP9:%.*]] = load i32, ptr @global, align 4
; CHECK-NEXT: [[TMP10]] = add i32 [[TMP9]], [[ACCUMULATOR_TR]]
; CHECK-NEXT: br label [[TAILRECURSE]]
;
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 ptr %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(ptr %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
%tmp9 = load i32, ptr @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(ptr %a_arg, i32 %a_len_arg, i32 %start_arg) nounwind readonly willreturn {
; CHECK-LABEL: @raise_load_3(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[TAILRECURSE:%.*]]
; CHECK: tailrecurse:
; CHECK-NEXT: [[ACCUMULATOR_TR:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP10:%.*]], [[ELSE:%.*]] ]
; CHECK-NEXT: [[START_ARG_TR:%.*]] = phi i32 [ [[START_ARG:%.*]], [[ENTRY]] ], [ [[TMP7:%.*]], [[ELSE]] ]
; CHECK-NEXT: [[TMP2:%.*]] = icmp sge i32 [[START_ARG_TR]], [[A_LEN_ARG:%.*]]
; CHECK-NEXT: br i1 [[TMP2]], label [[IF:%.*]], label [[ELSE]]
; CHECK: if:
; CHECK-NEXT: [[ACCUMULATOR_RET_TR:%.*]] = add i32 0, [[ACCUMULATOR_TR]]
; CHECK-NEXT: ret i32 [[ACCUMULATOR_RET_TR]]
; CHECK: else:
; CHECK-NEXT: [[TMP7]] = add i32 [[START_ARG_TR]], 1
; CHECK-NEXT: [[TMP9:%.*]] = load i32, ptr @extern_weak_global, align 4
; CHECK-NEXT: [[TMP10]] = add i32 [[TMP9]], [[ACCUMULATOR_TR]]
; CHECK-NEXT: br label [[TAILRECURSE]]
;
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(ptr %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
%tmp9 = load i32, ptr @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(ptr %a_arg, i32 %a_len_arg, i32 %start_arg) readonly {
; CHECK-LABEL: @raise_load_4(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[TAILRECURSE:%.*]]
; CHECK: tailrecurse:
; CHECK-NEXT: [[ACCUMULATOR_TR:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP10:%.*]], [[RECURSE:%.*]] ]
; CHECK-NEXT: [[A_LEN_ARG_TR:%.*]] = phi i32 [ [[A_LEN_ARG:%.*]], [[ENTRY]] ], [ [[FIRST:%.*]], [[RECURSE]] ]
; CHECK-NEXT: [[START_ARG_TR:%.*]] = phi i32 [ [[START_ARG:%.*]], [[ENTRY]] ], [ [[TMP7:%.*]], [[RECURSE]] ]
; CHECK-NEXT: [[TMP2:%.*]] = icmp sge i32 [[START_ARG_TR]], [[A_LEN_ARG_TR]]
; CHECK-NEXT: br i1 [[TMP2]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: [[ACCUMULATOR_RET_TR:%.*]] = add i32 0, [[ACCUMULATOR_TR]]
; CHECK-NEXT: ret i32 [[ACCUMULATOR_RET_TR]]
; CHECK: else:
; CHECK-NEXT: [[NULLCHECK:%.*]] = icmp eq ptr [[A_ARG:%.*]], null
; CHECK-NEXT: br i1 [[NULLCHECK]], label [[UNWIND:%.*]], label [[RECURSE]]
; CHECK: unwind:
; CHECK-NEXT: unreachable
; CHECK: recurse:
; CHECK-NEXT: [[TMP7]] = add i32 [[START_ARG_TR]], 1
; CHECK-NEXT: [[FIRST]] = load i32, ptr [[A_ARG]], align 4
; CHECK-NEXT: [[SECOND:%.*]] = load i32, ptr [[A_ARG]], align 4
; CHECK-NEXT: [[TMP10]] = add i32 [[SECOND]], [[ACCUMULATOR_TR]]
; CHECK-NEXT: br label [[TAILRECURSE]]
;
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 ptr %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, ptr %a_arg ; <i32> [#uses=1]
%tmp8 = call fastcc i32 @raise_load_4(ptr %a_arg, i32 %first, i32 %tmp7) ; <i32> [#uses=1]
%second = load i32, ptr %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(ptr dereferenceable(4) align 4 %a_arg, i32 %a_len_arg, i32 %start_arg) readonly nofree nosync {
; CHECK-LABEL: @raise_load_5(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[TAILRECURSE:%.*]]
; CHECK: tailrecurse:
; CHECK-NEXT: [[ACCUMULATOR_TR:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP10:%.*]], [[ELSE:%.*]] ]
; CHECK-NEXT: [[START_ARG_TR:%.*]] = phi i32 [ [[START_ARG:%.*]], [[ENTRY]] ], [ [[TMP7:%.*]], [[ELSE]] ]
; CHECK-NEXT: [[TMP2:%.*]] = icmp sge i32 [[START_ARG_TR]], [[A_LEN_ARG:%.*]]
; CHECK-NEXT: br i1 [[TMP2]], label [[IF:%.*]], label [[ELSE]]
; CHECK: if:
; CHECK-NEXT: [[ACCUMULATOR_RET_TR:%.*]] = add i32 0, [[ACCUMULATOR_TR]]
; CHECK-NEXT: ret i32 [[ACCUMULATOR_RET_TR]]
; CHECK: else:
; CHECK-NEXT: [[TMP7]] = add i32 [[START_ARG_TR]], 1
; CHECK-NEXT: [[TMP9:%.*]] = load i32, ptr [[A_ARG:%.*]], align 4
; CHECK-NEXT: [[TMP10]] = add i32 [[TMP9]], [[ACCUMULATOR_TR]]
; CHECK-NEXT: br label [[TAILRECURSE]]
;
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(ptr %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
%tmp9 = load i32, ptr %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(ptr %a_arg, i32 %a_len_arg, i32 %start_arg) nounwind {
; CHECK-LABEL: @raise_load_6(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[S:%.*]] = alloca i32, align 4
; CHECK-NEXT: br label [[TAILRECURSE:%.*]]
; CHECK: tailrecurse:
; CHECK-NEXT: [[ACCUMULATOR_TR:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP10:%.*]], [[ELSE:%.*]] ]
; CHECK-NEXT: [[START_ARG_TR:%.*]] = phi i32 [ [[START_ARG:%.*]], [[ENTRY]] ], [ [[TMP7:%.*]], [[ELSE]] ]
; CHECK-NEXT: store i32 4, ptr [[S]], align 4
; CHECK-NEXT: [[TMP2:%.*]] = icmp sge i32 [[START_ARG_TR]], [[A_LEN_ARG:%.*]]
; CHECK-NEXT: br i1 [[TMP2]], label [[IF:%.*]], label [[ELSE]]
; CHECK: if:
; CHECK-NEXT: store i32 1, ptr [[A_ARG:%.*]], align 4
; CHECK-NEXT: [[ACCUMULATOR_RET_TR:%.*]] = add i32 0, [[ACCUMULATOR_TR]]
; CHECK-NEXT: ret i32 [[ACCUMULATOR_RET_TR]]
; CHECK: else:
; CHECK-NEXT: [[TMP7]] = add i32 [[START_ARG_TR]], 1
; CHECK-NEXT: [[TMP9:%.*]] = load i32, ptr [[S]], align 4
; CHECK-NEXT: [[TMP10]] = add i32 [[TMP9]], [[ACCUMULATOR_TR]]
; CHECK-NEXT: br label [[TAILRECURSE]]
;
entry:
%s = alloca i32
store i32 4, ptr %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, ptr %a_arg
ret i32 0
else: ; preds = %entry
%tmp7 = add i32 %start_arg, 1 ; <i32> [#uses=1]
%tmp8 = call fastcc i32 @raise_load_6(ptr %a_arg, i32 %a_len_arg, i32 %tmp7) ; <i32> [#uses=1]
%tmp9 = load i32, ptr %s ; <i32> [#uses=1]
%tmp10 = add i32 %tmp9, %tmp8 ; <i32> [#uses=1]
ret i32 %tmp10
}
|
