llvm-project/llvm/test/Transforms/CodeGenPrepare/skip-merging-case-block.ll

201 lines
7.4 KiB
LLVM

; RUN: opt -codegenprepare < %s -mtriple=aarch64-none-linux-gnu -S | FileCheck %s
target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
target triple = "aarch64--linux-gnu"
; Expect to skip merging two empty blocks (sw.bb and sw.bb2) into sw.epilog
; as both of them are unlikely executed.
define i32 @f_switch(i32 %c) {
; CHECK-LABEL: @f_switch
; CHECK-LABEL: entry:
; CHECK: i32 10, label %sw.bb
; CHECK: i32 20, label %sw.bb2
entry:
switch i32 %c, label %sw.default [
i32 10, label %sw.bb
i32 20, label %sw.bb2
i32 30, label %sw.bb3
i32 40, label %sw.bb4
], !prof !0
sw.bb: ; preds = %entry
br label %sw.epilog
sw.bb2: ; preds = %entry
br label %sw.epilog
sw.bb3: ; preds = %entry
call void bitcast (void (...)* @callcase3 to void ()*)()
br label %sw.epilog
sw.bb4: ; preds = %entry
call void bitcast (void (...)* @callcase4 to void ()*)()
br label %sw.epilog
sw.default: ; preds = %entry
call void bitcast (void (...)* @calldefault to void ()*)()
br label %sw.epilog
; CHECK-LABEL: sw.epilog:
; CHECK: %fp.0 = phi void (...)* [ @FD, %sw.default ], [ @F4, %sw.bb4 ], [ @F3, %sw.bb3 ], [ @F2, %sw.bb2 ], [ @F1, %sw.bb ]
sw.epilog: ; preds = %sw.default, %sw.bb3, %sw.bb2, %sw.bb
%fp.0 = phi void (...)* [ @FD, %sw.default ], [ @F4, %sw.bb4 ], [ @F3, %sw.bb3 ], [ @F2, %sw.bb2 ], [ @F1, %sw.bb ]
%callee.knr.cast = bitcast void (...)* %fp.0 to void ()*
call void %callee.knr.cast()
ret i32 0
}
; Expect not to merge sw.bb2 because of the conflict in the incoming value from
; sw.bb which is already merged.
define i32 @f_switch2(i32 %c) {
; CHECK-LABEL: @f_switch2
; CHECK-LABEL: entry:
; CHECK: i32 10, label %sw.epilog
; CHECK: i32 20, label %sw.bb2
entry:
switch i32 %c, label %sw.default [
i32 10, label %sw.bb
i32 20, label %sw.bb2
i32 30, label %sw.bb3
i32 40, label %sw.bb4
], !prof !1
sw.bb: ; preds = %entry
br label %sw.epilog
sw.bb2: ; preds = %entry
br label %sw.epilog
sw.bb3: ; preds = %entry
call void bitcast (void (...)* @callcase3 to void ()*)()
br label %sw.epilog
sw.bb4: ; preds = %entry
call void bitcast (void (...)* @callcase4 to void ()*)()
br label %sw.epilog
sw.default: ; preds = %entry
call void bitcast (void (...)* @calldefault to void ()*)()
br label %sw.epilog
; CHECK-LABEL: sw.epilog:
; CHECK: %fp.0 = phi void (...)* [ @FD, %sw.default ], [ @F4, %sw.bb4 ], [ @F3, %sw.bb3 ], [ @F2, %sw.bb2 ], [ @F1, %entry ]
sw.epilog: ; preds = %sw.default, %sw.bb3, %sw.bb2, %sw.bb
%fp.0 = phi void (...)* [ @FD, %sw.default ], [ @F4, %sw.bb4 ], [ @F3, %sw.bb3 ], [ @F2, %sw.bb2 ], [ @F1, %sw.bb ]
%callee.knr.cast = bitcast void (...)* %fp.0 to void ()*
call void %callee.knr.cast()
ret i32 0
}
; Multiple empty blocks should be considered together if all incoming values
; from them are same. We expect to merge both empty blocks (sw.bb and sw.bb2)
; because the sum of frequencies are higer than the threshold.
define i32 @f_switch3(i32 %c) {
; CHECK-LABEL: @f_switch3
; CHECK-LABEL: entry:
; CHECK: i32 10, label %sw.epilog
; CHECK: i32 20, label %sw.epilog
entry:
switch i32 %c, label %sw.default [
i32 10, label %sw.bb
i32 20, label %sw.bb2
i32 30, label %sw.bb3
i32 40, label %sw.bb4
], !prof !2
sw.bb: ; preds = %entry
br label %sw.epilog
sw.bb2: ; preds = %entry
br label %sw.epilog
sw.bb3: ; preds = %entry
call void bitcast (void (...)* @callcase3 to void ()*)()
br label %sw.epilog
sw.bb4: ; preds = %entry
call void bitcast (void (...)* @callcase4 to void ()*)()
br label %sw.epilog
sw.default: ; preds = %entry
call void bitcast (void (...)* @calldefault to void ()*)()
br label %sw.epilog
; CHECK-LABEL: sw.epilog:
; CHECK: %fp.0 = phi void (...)* [ @FD, %sw.default ], [ @F4, %sw.bb4 ], [ @F3, %sw.bb3 ], [ @F1, %entry ], [ @F1, %entry ]
sw.epilog: ; preds = %sw.default, %sw.bb3, %sw.bb2, %sw.bb
%fp.0 = phi void (...)* [ @FD, %sw.default ], [ @F4, %sw.bb4 ], [ @F3, %sw.bb3 ], [ @F1, %sw.bb2 ], [ @F1, %sw.bb ]
%callee.knr.cast = bitcast void (...)* %fp.0 to void ()*
call void %callee.knr.cast()
ret i32 0
}
declare void @F1(...) local_unnamed_addr
declare void @F2(...) local_unnamed_addr
declare void @F3(...) local_unnamed_addr
declare void @F4(...) local_unnamed_addr
declare void @FD(...) local_unnamed_addr
declare void @callcase3(...) local_unnamed_addr
declare void @callcase4(...) local_unnamed_addr
declare void @calldefault(...) local_unnamed_addr
!0 = !{!"branch_weights", i32 5, i32 1, i32 1,i32 5, i32 5}
!1 = !{!"branch_weights", i32 1 , i32 5, i32 1,i32 1, i32 1}
!2 = !{!"branch_weights", i32 1 , i32 4, i32 1,i32 1, i32 1}
; This test that BFI/BPI is created without any assertion in isMergingEmptyBlockProfitable()
; in the case where empty blocks are removed before creating BFI/BPI.
@b = common global i32 0, align 4
@a = common global i32* null, align 8
define i32 @should_not_assert(i32 %i) local_unnamed_addr {
entry:
%0 = load i32, i32* @b, align 4
%cond = icmp eq i32 %0, 6
br i1 %cond, label %while.cond.preheader, label %sw.epilog
while.cond.preheader: ; preds = %entry
%1 = load i32*, i32** @a, align 8
%magicptr = ptrtoint i32* %1 to i64
%arrayidx = getelementptr inbounds i32, i32* %1, i64 1
br label %while.cond
while.cond: ; preds = %while.cond.preheader, %land.rhs
switch i64 %magicptr, label %land.rhs [
i64 32, label %while.cond2.loopexit
i64 0, label %while.cond2.loopexit
]
land.rhs: ; preds = %while.cond
%2 = load i32, i32* %arrayidx, align 4
%tobool1 = icmp eq i32 %2, 0
br i1 %tobool1, label %while.cond2thread-pre-split.loopexit, label %while.cond
while.cond2thread-pre-split.loopexit: ; preds = %land.rhs
br label %while.cond2thread-pre-split
while.cond2thread-pre-split: ; preds = %while.cond2thread-pre-split.loopexit, %while.body4
%.pr = phi i32* [ %.pr.pre, %while.body4 ], [ %1, %while.cond2thread-pre-split.loopexit ]
br label %while.cond2
while.cond2.loopexit: ; preds = %while.cond, %while.cond
br label %while.cond2
while.cond2: ; preds = %while.cond2.loopexit, %while.cond2thread-pre-split
%3 = phi i32* [ %.pr, %while.cond2thread-pre-split ], [ %1, %while.cond2.loopexit ]
%tobool3 = icmp eq i32* %3, null
br i1 %tobool3, label %sw.epilog, label %while.body4
while.body4: ; preds = %while.cond2
tail call void bitcast (void (...)* @fn2 to void ()*)()
%.pr.pre = load i32*, i32** @a, align 8
br label %while.cond2thread-pre-split
sw.epilog: ; preds = %while.cond2, %entry
ret i32 undef
}
declare void @fn2(...) local_unnamed_addr