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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; REQUIRES: x86-registered-target
; RUN: opt < %s -passes=rel-lookup-table-converter -relocation-model=pic -S | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@.str = private unnamed_addr constant [5 x i8] c"zero\00", align 1
@.str.1 = private unnamed_addr constant [4 x i8] c"one\00", align 1
@.str.2 = private unnamed_addr constant [4 x i8] c"two\00", align 1
@.str.3 = private unnamed_addr constant [8 x i8] c"default\00", align 1
@.str.4 = private unnamed_addr constant [6 x i8] c"three\00", align 1
@.str.5 = private unnamed_addr constant [5 x i8] c"str1\00", align 1
@.str.6 = private unnamed_addr constant [5 x i8] c"str2\00", align 1
@.str.7 = private unnamed_addr constant [12 x i8] c"singlevalue\00", align 1
@.str.8 = private unnamed_addr constant [2 x i8] c"a\00", align 1
@.str.9 = private unnamed_addr constant [2 x i8] c"b\00", align 1
@.str.10 = private unnamed_addr constant [2 x i8] c"c\00", align 1
@a1 = external global i32, align 4
@b1 = external global i32, align 4
@c1 = external global i32, align 4
@d1 = external global i32, align 4
@a2 = internal constant i32 0, align 4
@b2 = internal constant i32 0, align 4
@c2 = internal constant i32 0, align 4
@d2 = internal constant i32 0, align 4
@switch.table.external_linkage = private unnamed_addr constant [3 x ptr] [ptr @a1, ptr @b1, ptr @c1], align 8
@switch.table.internal_linkage = private unnamed_addr constant [3 x ptr] [ptr @a2, ptr @b2, ptr @c2], align 8
@switch.table.string_table = private unnamed_addr constant [3 x ptr]
[
ptr @.str,
ptr @.str.1,
ptr @.str.2
], align 8
@switch.table.string_table_holes = private unnamed_addr constant [4 x ptr]
[
ptr @.str,
ptr @.str.3,
ptr @.str.2,
ptr @.str.4
], align 8
@switch.table.single_value = private unnamed_addr constant [3 x ptr]
[
ptr @.str,
ptr @.str.1,
ptr @.str.2
], align 8
@user_defined_lookup_table.table = internal unnamed_addr constant [3 x ptr]
[
ptr @.str,
ptr @.str.1,
ptr @.str.2
], align 16
@table = internal constant [2 x ptr] [
ptr @.str.8,
ptr @.str.9
], align 16
@table2 = internal constant [2 x ptr] [
ptr @.str.8,
ptr @.str.9
], align 16
; Lookup table check for integer pointers that have external linkage
; CHECK: @switch.table.external_linkage = private unnamed_addr constant [3 x ptr] [ptr @a1, ptr @b1, ptr @c1], align
; Lookup table check for integer pointers that have internal linkage
; CHECK: @reltable.internal_linkage = private unnamed_addr constant [3 x i32]
; CHECK-SAME: [
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @a2 to i64), i64 ptrtoint (ptr @reltable.internal_linkage to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @b2 to i64), i64 ptrtoint (ptr @reltable.internal_linkage to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @c2 to i64), i64 ptrtoint (ptr @reltable.internal_linkage to i64)) to i32)
; CHECK-SAME: ], align 4
; Relative switch lookup table for strings
; CHECK: @reltable.string_table = private unnamed_addr constant [3 x i32]
; CHECK-SAME: [
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str to i64), i64 ptrtoint (ptr @reltable.string_table to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.1 to i64), i64 ptrtoint (ptr @reltable.string_table to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.2 to i64), i64 ptrtoint (ptr @reltable.string_table to i64)) to i32)
; CHECK-SAME: ], align 4
; Relative switch lookup table for strings with holes, where holes are filled with relative offset to default values
; CHECK: @reltable.string_table_holes = private unnamed_addr constant [4 x i32]
; CHECK-SAME: [
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str to i64), i64 ptrtoint (ptr @reltable.string_table_holes to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.3 to i64), i64 ptrtoint (ptr @reltable.string_table_holes to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.2 to i64), i64 ptrtoint (ptr @reltable.string_table_holes to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.4 to i64), i64 ptrtoint (ptr @reltable.string_table_holes to i64)) to i32)
; CHECK-SAME: ], align 4
; Single value check
; CHECK: @reltable.single_value = private unnamed_addr constant [3 x i32]
; CHECK-SAME: [
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str to i64), i64 ptrtoint (ptr @reltable.single_value to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.1 to i64), i64 ptrtoint (ptr @reltable.single_value to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.2 to i64), i64 ptrtoint (ptr @reltable.single_value to i64)) to i32)
; CHECK-SAME: ], align 4
;
; Relative lookup table for the loop hoist check test
; CHECK: @reltable.loop_hoist = internal unnamed_addr constant [2 x i32]
; CHECK-SAME: [
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.8 to i64), i64 ptrtoint (ptr @reltable.loop_hoist to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.9 to i64), i64 ptrtoint (ptr @reltable.loop_hoist to i64)) to i32)
; CHECK-SAME: ], align 4
; Relative look up table for the test where gep is not immediately followed by a load check
; CHECK: @reltable.gep_is_not_imm_followed_by_load = internal unnamed_addr constant [2 x i32]
; CHECK-SAME: [
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.8 to i64), i64 ptrtoint (ptr @reltable.gep_is_not_imm_followed_by_load to i64)) to i32),
; CHECK-SAME: i32 trunc (i64 sub (i64 ptrtoint (ptr @.str.9 to i64), i64 ptrtoint (ptr @reltable.gep_is_not_imm_followed_by_load to i64)) to i32)
; CHECK-SAME: ], align 4
; Lookup table check for integer pointers that have external linkage
define ptr @external_linkage(i32 %cond) {
; CHECK-LABEL: @external_linkage(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[COND:%.*]], 3
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [3 x ptr], ptr @switch.table.external_linkage, i32 0, i32 [[COND:%.*]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load ptr, ptr [[SWITCH_GEP]], align 8
; CHECK-NEXT: ret ptr [[SWITCH_LOAD]]
; CHECK: return:
; CHECK-NEXT: ret ptr @d1
;
entry:
%0 = icmp ult i32 %cond, 3
br i1 %0, label %switch.lookup, label %return
switch.lookup: ; preds = %entry
%switch.gep = getelementptr inbounds [3 x ptr], ptr @switch.table.external_linkage, i32 0, i32 %cond
%switch.load = load ptr, ptr %switch.gep, align 8
ret ptr %switch.load
return: ; preds = %entry
ret ptr @d1
}
; Relative switch lookup table for integer pointers that have internal linkage
define ptr @internal_linkage(i32 %cond) {
; CHECK-LABEL: @internal_linkage(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[COND:%.*]], 3
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[RELTABLE_SHIFT:%.*]] = shl i32 %cond, 2
; CHECK-NEXT: [[RELTABLE_INTRINSIC:%.*]] = call ptr @llvm.load.relative.i32(ptr @reltable.internal_linkage, i32 [[RELTABLE_SHIFT]])
; CHECK-NEXT: ret ptr [[RELTABLE_INTRINSIC]]
; CHECK: return:
; CHECK-NEXT: ret ptr @d2
;
entry:
%0 = icmp ult i32 %cond, 3
br i1 %0, label %switch.lookup, label %return
switch.lookup: ; preds = %entry
%switch.gep = getelementptr inbounds [3 x ptr], ptr @switch.table.internal_linkage, i32 0, i32 %cond
%switch.load = load ptr, ptr %switch.gep, align 8
ret ptr %switch.load
return: ; preds = %entry
ret ptr @d2
}
; ; Relative switch lookup table for strings
define ptr @string_table(i32 %cond) {
; CHECK-LABEL: @string_table(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[COND:%.*]], 3
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[RELTABLE_SHIFT:%.*]] = shl i32 %cond, 2
; CHECK-NEXT: [[RELTABLE_INTRINSIC:%.*]] = call ptr @llvm.load.relative.i32(ptr @reltable.string_table, i32 [[RELTABLE_SHIFT]])
; CHECK-NEXT: ret ptr [[RELTABLE_INTRINSIC]]
; CHECK: return:
; CHECK-NEXT: ret ptr @.str.3
;
entry:
%0 = icmp ult i32 %cond, 3
br i1 %0, label %switch.lookup, label %return
switch.lookup: ; preds = %entry
%switch.gep = getelementptr inbounds [3 x ptr], ptr @switch.table.string_table, i32 0, i32 %cond
%switch.load = load ptr, ptr %switch.gep, align 8
ret ptr %switch.load
return: ; preds = %entry
ret ptr @.str.3
}
; Relative switch lookup table for strings with holes, where holes are filled with relative offset to default values
define ptr @string_table_holes(i32 %cond) {
; CHECK-LABEL: @string_table_holes(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[COND:%.*]], 4
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[RELTABLE_SHIFT:%.*]] = shl i32 [[COND]], 2
; CHECK-NEXT: [[RELTABLE_INTRINSIC:%.*]] = call ptr @llvm.load.relative.i32(ptr @reltable.string_table_holes, i32 [[RELTABLE_SHIFT]])
; CHECK-NEXT: ret ptr [[RELTABLE_INTRINSIC]]
; CHECK: return:
; CHECK-NEXT: ret ptr @.str.3
;
entry:
%0 = icmp ult i32 %cond, 4
br i1 %0, label %switch.lookup, label %return
switch.lookup: ; preds = %entry
%switch.gep = getelementptr inbounds [4 x ptr], ptr @switch.table.string_table_holes, i32 0, i32 %cond
%switch.load = load ptr, ptr %switch.gep, align 8
ret ptr %switch.load
return: ; preds = %entry
ret ptr @.str.3
}
; Single value check
; If there is a lookup table, where each element contains the same value,
; a relative lookup should not be generated
define void @single_value(i32 %cond) {
; CHECK-LABEL: @single_value(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[COND:%.*]], 3
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[RELTABLE_SHIFT:%.*]] = shl i32 [[COND]], 2
; CHECK-NEXT: [[RELTABLE_INTRINSIC:%.*]] = call ptr @llvm.load.relative.i32(ptr @reltable.single_value, i32 [[RELTABLE_SHIFT]])
; CHECK: sw.epilog:
; CHECK-NEXT: [[STR1:%.*]] = phi ptr [ @.str.5, %entry ], [ @.str.7, %switch.lookup ]
; CHECK-NEXT: [[STR2:%.*]] = phi ptr [ @.str.6, %entry ], [ [[RELTABLE_INTRINSIC]], [[SWITCH_LOOKUP]] ]
; CHECK-NEXT: ret void
entry:
%0 = icmp ult i32 %cond, 3
br i1 %0, label %switch.lookup, label %sw.epilog
switch.lookup: ; preds = %entry
%switch.gep = getelementptr inbounds [3 x ptr], ptr @switch.table.single_value, i32 0, i32 %cond
%switch.load = load ptr, ptr %switch.gep, align 8
br label %sw.epilog
sw.epilog: ; preds = %switch.lookup, %entry
%str1.0 = phi ptr [ @.str.5, %entry ], [ @.str.7, %switch.lookup ]
%str2.0 = phi ptr [ @.str.6, %entry ], [ %switch.load, %switch.lookup ]
ret void
}
; Relative lookup table generated for a user-defined lookup table
define ptr @user_defined_lookup_table(i32 %cond) {
; CHECK-LABEL: @user_defined_lookup_table(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[COND:%.*]], 3
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: cond.false:
; CHECK-NEXT: [[IDX_PROM:%.*]] = sext i32 [[COND]] to i64
; CHECK-NEXT: [[RELTABLE_SHIFT:%.*]] = shl i64 [[IDX_PROM]], 2
; CHECK-NEXT: [[RELTABLE_INTRINSIC:%.*]] = call ptr @llvm.load.relative.i64(ptr @reltable.user_defined_lookup_table, i64 [[RELTABLE_SHIFT]])
; CHECK-NEXT: br label %cond.end
; CHECK: cond.end:
; CHECK-NEXT: [[COND1:%.*]] = phi ptr [ [[RELTABLE_INTRINSIC]], %cond.false ], [ @.str.3, %entry ]
; CHECK-NEXT: ret ptr [[COND1]]
;
entry:
%cmp = icmp sgt i32 %cond, 3
br i1 %cmp, label %cond.end, label %cond.false
cond.false: ; preds = %entry
%idxprom = sext i32 %cond to i64
%arrayidx = getelementptr inbounds [3 x ptr], ptr @user_defined_lookup_table.table, i64 0, i64 %idxprom
%0 = load ptr, ptr %arrayidx, align 8, !tbaa !4
br label %cond.end
cond.end: ; preds = %entry, %cond.false
%cond1 = phi ptr [ %0, %cond.false ], [ @.str.3, %entry ]
ret ptr %cond1
}
; Check to ensure that call @llvm.load.relative is inserted before load, not before gep.
; When a lookup table is accessed inside a loop, and a gep is hosted outside the loop via licm,
; make sure that call @llvm.load.relative is inserted before load.
define ptr @loop_hoist(i32 %x) {
; CHECK-LABEL: @loop_hoist(i32 %x)
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 1
; CHECK-NEXT: [[RELTABLE_SHIFT:%.*]] = shl i32 [[X:%.*]], 2
; CHECK-NEXT: br i1 [[TMP0]], label %if.done, label %if.false
; CHECK: if.false:
; CHECK-NEXT: [[RELTABLE_INTRINSIC:%.*]] = call ptr @llvm.load.relative.i32(ptr @reltable.loop_hoist, i32 [[RELTABLE_SHIFT]])
; CHECK-NEXT: br label %if.done
; CHECK: if.done:
; CHECK-NEXT: [[TMP2:%.*]] = phi ptr [ @.str.10, %entry ], [ [[RELTABLE_INTRINSIC]], %if.false ]
; CHECK-NEXT: ret ptr [[TMP2]]
;
entry:
%0 = icmp sgt i32 %x, 1
%1 = getelementptr [2 x ptr], ptr @table, i32 0, i32 %x
br i1 %0, label %if.done, label %if.false
if.false:
%2 = load ptr, ptr %1
br label %if.done
if.done:
%3 = phi ptr [ @.str.10, %entry ], [ %2, %if.false ]
ret ptr %3
}
; Another check to ensure that call @llvm.load.relative is inserted before load but not before gep.
; When a lookup table is accessed, and gep is not immediately followed by a load (like if there is a function call
; or an exception in between), make sure that call @llvm.load.relative is inserted before load.
; CHECK-LABEL: @may_not_return()
declare void @may_not_return()
define ptr @gep_is_not_imm_followed_by_load(i32 %x) {
; CHECK-LABEL: @gep_is_not_imm_followed_by_load(i32 %x)
; CHECK: entry:
; CHECK-NEXT: [[RELTABLE_SHIFT:%.*]] = shl i32 [[X:%.*]], 2
; CHECK-NEXT: call void @may_not_return()
; CHECK-NEXT: [[RELTABLE_INTRINSIC:%.*]] = call ptr @llvm.load.relative.i32(ptr @reltable.gep_is_not_imm_followed_by_load, i32 [[RELTABLE_SHIFT]])
; CHECK-NEXT: ret ptr [[RELTABLE_INTRINSIC]]
;
entry:
%0 = getelementptr [2 x ptr], ptr @table2, i32 0, i32 %x
call void @may_not_return()
%1 = load ptr, ptr %0
ret ptr %1
}
!llvm.module.flags = !{!0, !1}
!0 = !{i32 7, !"PIC Level", i32 2}
!1 = !{i32 1, !"Code Model", i32 1}
!4 = !{!"any pointer", !5, i64 0}
!5 = !{!"omnipotent char", !6, i64 0}
!6 = !{!"Simple C/C++ TBAA"}
|
