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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=simplifycfg -switch-to-lookup=true -keep-loops=false -S -mattr=+f | FileCheck %s
; RUN: opt < %s -passes='simplifycfg<no-keep-loops;switch-to-lookup>' -S -mattr=+f | FileCheck %s
target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n64-S128"
target triple = "riscv64-unknown-elf"
; The table for @f
; CHECK: @switch.table.f = private unnamed_addr constant [7 x i32] [i32 55, i32 123, i32 0, i32 -1, i32 27, i32 62, i32 1], align 4
; The char table for char
; CHECK: @switch.table.char = private unnamed_addr constant [9 x i8] c"7{\00\FF\1B>\01!T", align 1
; The float table for @h
; CHECK: @switch.table.h = private unnamed_addr constant [4 x float] [float 0x40091EB860000000, float 0x3FF3BE76C0000000, float 0x4012449BA0000000, float 0x4001AE1480000000], align 4
; The table for @foostring
; CHECK: @switch.table.foostring = private unnamed_addr constant [4 x ptr] [ptr @.str, ptr @.str1, ptr @.str2, ptr @.str3], align 8
; A simple int-to-int selection switch.
; It is dense enough to be replaced by table lookup.
; The result is directly by a ret from an otherwise empty bb,
; so we return early, directly from the lookup bb.
define i32 @f(i32 %c) {
; CHECK-LABEL: @f(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[SWITCH_TABLEIDX:%.*]] = sub i32 [[C:%.*]], 42
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[SWITCH_TABLEIDX]], 7
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [7 x i32], ptr @switch.table.f, i32 0, i32 [[SWITCH_TABLEIDX]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RETVAL_0:%.*]] = phi i32 [ [[SWITCH_LOAD]], [[SWITCH_LOOKUP]] ], [ 15, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RETVAL_0]]
;
entry:
switch i32 %c, label %sw.default [
i32 42, label %return
i32 43, label %sw.bb1
i32 44, label %sw.bb2
i32 45, label %sw.bb3
i32 46, label %sw.bb4
i32 47, label %sw.bb5
i32 48, label %sw.bb6
]
sw.bb1: br label %return
sw.bb2: br label %return
sw.bb3: br label %return
sw.bb4: br label %return
sw.bb5: br label %return
sw.bb6: br label %return
sw.default: br label %return
return:
%retval.0 = phi i32 [ 15, %sw.default ], [ 1, %sw.bb6 ], [ 62, %sw.bb5 ], [ 27, %sw.bb4 ], [ -1, %sw.bb3 ], [ 0, %sw.bb2 ], [ 123, %sw.bb1 ], [ 55, %entry ]
ret i32 %retval.0
}
; Same thing, but with i8's
define i8 @char(i32 %c) {
; CHECK-LABEL: @char(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[SWITCH_TABLEIDX:%.*]] = sub i32 [[C:%.*]], 42
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[SWITCH_TABLEIDX]], 9
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [9 x i8], ptr @switch.table.char, i32 0, i32 [[SWITCH_TABLEIDX]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i8, ptr [[SWITCH_GEP]], align 1
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RETVAL_0:%.*]] = phi i8 [ [[SWITCH_LOAD]], [[SWITCH_LOOKUP]] ], [ 15, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i8 [[RETVAL_0]]
;
entry:
switch i32 %c, label %sw.default [
i32 42, label %return
i32 43, label %sw.bb1
i32 44, label %sw.bb2
i32 45, label %sw.bb3
i32 46, label %sw.bb4
i32 47, label %sw.bb5
i32 48, label %sw.bb6
i32 49, label %sw.bb7
i32 50, label %sw.bb8
]
sw.bb1: br label %return
sw.bb2: br label %return
sw.bb3: br label %return
sw.bb4: br label %return
sw.bb5: br label %return
sw.bb6: br label %return
sw.bb7: br label %return
sw.bb8: br label %return
sw.default: br label %return
return:
%retval.0 = phi i8 [ 15, %sw.default ], [ 84, %sw.bb8 ], [ 33, %sw.bb7 ], [ 1, %sw.bb6 ], [ 62, %sw.bb5 ], [ 27, %sw.bb4 ], [ -1, %sw.bb3 ], [ 0, %sw.bb2 ], [ 123, %sw.bb1 ], [ 55, %entry ]
ret i8 %retval.0
}
; A switch used to initialize two variables, an i8 and a float.
declare void @dummy(i8 signext, float)
define void @h(i32 %x) {
; CHECK-LABEL: @h(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[X:%.*]], 4
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[SW_EPILOG:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_SHIFTAMT:%.*]] = mul i32 [[X]], 8
; CHECK-NEXT: [[SWITCH_DOWNSHIFT:%.*]] = lshr i32 89655594, [[SWITCH_SHIFTAMT]]
; CHECK-NEXT: [[SWITCH_MASKED:%.*]] = trunc i32 [[SWITCH_DOWNSHIFT]] to i8
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [4 x float], ptr @switch.table.h, i32 0, i32 [[X]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load float, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: br label [[SW_EPILOG]]
; CHECK: sw.epilog:
; CHECK-NEXT: [[A_0:%.*]] = phi i8 [ [[SWITCH_MASKED]], [[SWITCH_LOOKUP]] ], [ 7, [[ENTRY:%.*]] ]
; CHECK-NEXT: [[B_0:%.*]] = phi float [ [[SWITCH_LOAD]], [[SWITCH_LOOKUP]] ], [ 0x4023FAE140000000, [[ENTRY]] ]
; CHECK-NEXT: call void @dummy(i8 signext [[A_0]], float [[B_0]])
; CHECK-NEXT: ret void
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %sw.epilog
i32 1, label %sw.bb1
i32 2, label %sw.bb2
i32 3, label %sw.bb3
]
sw.bb1: br label %sw.epilog
sw.bb2: br label %sw.epilog
sw.bb3: br label %sw.epilog
sw.default: br label %sw.epilog
sw.epilog:
%a.0 = phi i8 [ 7, %sw.default ], [ 5, %sw.bb3 ], [ 88, %sw.bb2 ], [ 9, %sw.bb1 ], [ 42, %entry ]
%b.0 = phi float [ 0x4023FAE140000000, %sw.default ], [ 0x4001AE1480000000, %sw.bb3 ], [ 0x4012449BA0000000, %sw.bb2 ], [ 0x3FF3BE76C0000000, %sw.bb1 ], [ 0x40091EB860000000, %entry ]
call void @dummy(i8 signext %a.0, float %b.0)
ret void
}
; Switch used to return a string.
@.str = private unnamed_addr constant [4 x i8] c"foo\00", align 1
@.str1 = private unnamed_addr constant [4 x i8] c"bar\00", align 1
@.str2 = private unnamed_addr constant [4 x i8] c"baz\00", align 1
@.str3 = private unnamed_addr constant [4 x i8] c"qux\00", align 1
@.str4 = private unnamed_addr constant [6 x i8] c"error\00", align 1
define ptr @foostring(i32 %x) {
; CHECK-LABEL: @foostring(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[X:%.*]], 4
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [4 x ptr], ptr @switch.table.foostring, i32 0, i32 [[X]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load ptr, ptr [[SWITCH_GEP]], align 8
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RETVAL_0:%.*]] = phi ptr [ [[SWITCH_LOAD]], [[SWITCH_LOOKUP]] ], [ @.str4, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret ptr [[RETVAL_0]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %return
i32 1, label %sw.bb1
i32 2, label %sw.bb2
i32 3, label %sw.bb3
]
sw.bb1: br label %return
sw.bb2: br label %return
sw.bb3: br label %return
sw.default: br label %return
return:
%retval.0 = phi ptr [ @.str4, %sw.default ],
[ @.str3, %sw.bb3 ],
[ @.str2, %sw.bb2 ],
[ @.str1, %sw.bb1 ],
[ @.str, %entry ]
ret ptr %retval.0
}
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