[SimplifyCFG] auto-generate better checks; NFC

llvm-svn: 287953
This commit is contained in:
Sanjay Patel 2016-11-25 21:07:13 +00:00
parent d873e3a694
commit d1a147f9f4
1 changed files with 36 additions and 21 deletions

View File

@ -913,42 +913,57 @@ return:
; We build lookup tables for switches with three or more cases.
define i32 @threecases(i32 %c) {
; CHECK-LABEL: @threecases(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[SWITCH_TABLEIDX:%.*]] = sub i32 %c, 0
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[SWITCH_TABLEIDX]], 3
; CHECK-NEXT: br i1 [[TMP0]], label %switch.lookup, label %return
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [3 x i32], [3 x i32]* @switch.table.10, i32 0, i32 [[SWITCH_TABLEIDX]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, i32* [[SWITCH_GEP]]
; CHECK-NEXT: ret i32 [[SWITCH_LOAD]]
; CHECK: return:
; CHECK-NEXT: ret i32 3
;
entry:
switch i32 %c, label %sw.default [
i32 0, label %return
i32 1, label %sw.bb1
i32 2, label %sw.bb2
i32 0, label %return
i32 1, label %sw.bb1
i32 2, label %sw.bb2
]
sw.bb1: br label %return
sw.bb2: br label %return
sw.default: br label %return
sw.bb1:
br label %return
sw.bb2:
br label %return
sw.default:
br label %return
return:
%x = phi i32 [ 3, %sw.default ], [ 5, %sw.bb2 ], [ 7, %sw.bb1 ], [ 10, %entry ]
ret i32 %x
; CHECK-LABEL: @threecases(
; CHECK-NOT: switch i32
; CHECK: @switch.table
}
; We don't build tables for switches with two cases.
define i32 @twocases(i32 %c) {
; CHECK-LABEL: @twocases(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[SWITCH_SELECTCMP:%.*]] = icmp eq i32 %c, 1
; CHECK-NEXT: [[SWITCH_SELECT:%.*]] = select i1 [[SWITCH_SELECTCMP:%.*]], i32 7, i32 3
; CHECK-NEXT: [[SWITCH_SELECTCMP1:%.*]] = icmp eq i32 %c, 0
; CHECK-NEXT: [[SWITCH_SELECT2:%.*]] = select i1 [[SWITCH_SELECTCMP1]], i32 9, i32 [[SWITCH_SELECT]]
; CHECK-NEXT: ret i32 [[SWITCH_SELECT2]]
;
entry:
switch i32 %c, label %sw.default [
i32 0, label %return
i32 1, label %sw.bb1
i32 0, label %return
i32 1, label %sw.bb1
]
sw.bb1: br label %return
sw.default: br label %return
sw.bb1:
br label %return
sw.default:
br label %return
return:
%x = phi i32 [ 3, %sw.default ], [ 7, %sw.bb1 ], [ 9, %entry ]
ret i32 %x
; CHECK-LABEL: @twocases(
; CHECK-NOT: switch i32
; CHECK-NOT: @switch.table
; CHECK: %switch.selectcmp
; CHECK-NEXT: %switch.select
; CHECK-NEXT: %switch.selectcmp1
; CHECK-NEXT: %switch.select2
}
; Don't build tables for switches with TLS variables.
@ -1194,7 +1209,7 @@ return:
%retval.0 = phi i32 [ %r.0, %if.then ], [ 100, %if.end ]
ret i32 %retval.0
; CHECK-LABEL: @no_reuse_cmp(
; CHECK: [[S:%.+]] = select
; CHECK: [[S:%.+]] = select
; CHECK-NEXT: %cmp = icmp ne i32 [[S]], 0
; CHECK-NEXT: [[R:%.+]] = select i1 %cmp, i32 [[S]], i32 100
; CHECK-NEXT: ret i32 [[R]]