maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/llvm/test/Transforms/InstCombine/unrecognized_three-way-comp...

472 lines
13 KiB
LLVM
Raw Normal View History

[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; Various patterns of three-ways comparison that are not currently recognized.
; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
declare void @foo(i32 %x)
define i32 @compare_against_arbitrary_value(i32 %x, i32 %c) {
; TODO: We can prove that if %x s> %c then %x != c, so there should be no actual
; calculations in callfoo block. @foo can be invoked with 1. We only do it
; for constants that are not 0 currently while it could be generalized.
; CHECK-LABEL: @compare_against_arbitrary_value(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], [[C:%.*]]
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i32 [[X]], [[C]]
; CHECK-NEXT: [[SELECT2:%.*]] = zext i1 [[CMP1]] to i32
; CHECK-NEXT: call void @foo(i32 [[SELECT2]])
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, %c
%cmp2 = icmp slt i32 %x, %c
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_zero(i32 %x) {
; CHECK-LABEL: @compare_against_zero(
; CHECK-NEXT: entry:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK: callfoo:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: call void @foo(i32 1)
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 0
%cmp2 = icmp slt i32 %x, 0
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_one(i32 %x) {
; CHECK-LABEL: @compare_against_one(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 1
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 1)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 1
%cmp2 = icmp slt i32 %x, 1
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_two(i32 %x) {
; CHECK-LABEL: @compare_against_two(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 2
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 1)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 2
%cmp2 = icmp slt i32 %x, 2
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_three(i32 %x) {
; CHECK-LABEL: @compare_against_three(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 3
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 1)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 3
%cmp2 = icmp slt i32 %x, 3
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_four(i32 %x) {
; CHECK-LABEL: @compare_against_four(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 4
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 1)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 4
%cmp2 = icmp slt i32 %x, 4
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_five(i32 %x) {
; CHECK-LABEL: @compare_against_five(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 5
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 1)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 5
%cmp2 = icmp slt i32 %x, 5
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_six(i32 %x) {
; CHECK-LABEL: @compare_against_six(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 6
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 1)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 6
%cmp2 = icmp slt i32 %x, 6
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
; Same as @compare_against_arbitrary_value, but now the three-way comparison
; returns not idiomatic comparator's result (-1, 0, 1) but some other constants.
define i32 @compare_against_arbitrary_value_non_idiomatic_1(i32 %x, i32 %c) {
; CHECK-LABEL: @compare_against_arbitrary_value_non_idiomatic_1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], [[C:%.*]]
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 425)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, %c
%cmp2 = icmp slt i32 %x, %c
%select1 = select i1 %cmp2, i32 -6, i32 425
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_zero_non_idiomatic_add(i32 %x) {
; CHECK-LABEL: @compare_against_zero_non_idiomatic_add(
; CHECK-NEXT: entry:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK: callfoo:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: call void @foo(i32 425)
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 0
%cmp2 = icmp slt i32 %x, 0
%select1 = select i1 %cmp2, i32 -6, i32 425
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
; Same as @compare_against_arbitrary_value, but now the three-way comparison
; returns not idiomatic comparator's result (-1, 0, 1) but some other constants.
define i32 @compare_against_arbitrary_value_non_idiomatic_2(i32 %x, i32 %c) {
; CHECK-LABEL: @compare_against_arbitrary_value_non_idiomatic_2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], [[C:%.*]]
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 425)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, %c
%cmp2 = icmp slt i32 %x, %c
%select1 = select i1 %cmp2, i32 -5, i32 425
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_zero_non_idiomatic_or(i32 %x) {
; CHECK-LABEL: @compare_against_zero_non_idiomatic_or(
; CHECK-NEXT: entry:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK: callfoo:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: call void @foo(i32 425)
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i32 %x, 0
%cmp2 = icmp slt i32 %x, 0
%select1 = select i1 %cmp2, i32 -5, i32 425
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_arbitrary_value_type_mismatch(i64 %x, i64 %c) {
; TODO: We can prove that if %x s> %c then %x != c, so there should be no actual
; calculations in callfoo block. @foo can be invoked with 1. We only do it
; for constants that are not 0 currently while it could be generalized.
; CHECK-LABEL: @compare_against_arbitrary_value_type_mismatch(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i64 [[X:%.*]], [[C:%.*]]
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i64 [[X]], [[C]]
; CHECK-NEXT: [[SELECT2:%.*]] = zext i1 [[CMP1]] to i32
; CHECK-NEXT: call void @foo(i32 [[SELECT2]])
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i64 %x, %c
%cmp2 = icmp slt i64 %x, %c
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_zero_type_mismatch_idiomatic(i64 %x) {
; CHECK-LABEL: @compare_against_zero_type_mismatch_idiomatic(
; CHECK-NEXT: entry:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i64 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK: callfoo:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: call void @foo(i32 1)
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i64 %x, 0
%cmp2 = icmp slt i64 %x, 0
%select1 = select i1 %cmp2, i32 -1, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_zero_type_mismatch_non_idiomatic_1(i64 %x) {
; CHECK-LABEL: @compare_against_zero_type_mismatch_non_idiomatic_1(
; CHECK-NEXT: entry:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i64 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK: callfoo:
[InstCombine] refine select-of-constants to bitwise ops Add logic for the special case when a cmp+select can clearly be reduced to just a bitwise logic instruction, and remove an over-reaching chunk of general purpose bit magic. The primary goal is to remove cases where we are not improving the IR instruction count when doing these select transforms, and in all cases here that is true. In the motivating 3-way compare tests, there are further improvements because we can combine/propagate select values (not sure if that belongs in instcombine, but it's there for now). DAGCombiner has folds to turn some of these selects into bit magic, so there should be no difference in the end result in those cases. Not all constant combinations are handled there yet, however, so it is possible that some targets will see more cmov/csel codegen with this change in IR canonicalization. Ideally, we'll go further to *not* turn selects into multiple logic/math ops in instcombine, and we'll canonicalize to selects. But we should make sure that this step does not result in regressions first (and if it does, we should fix those in the backend). The general direction for this change was discussed here: http://lists.llvm.org/pipermail/llvm-dev/2016-September/105373.html http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html Alive proofs for the new bit magic: https://rise4fun.com/Alive/XG7 Differential Revision: https://reviews.llvm.org/D46086 llvm-svn: 331486
2018-05-04 05:58:44 +08:00
; CHECK-NEXT: call void @foo(i32 1)
[NFC] Add some tests that demonstrate unrecognized three-way comparison patterns llvm-svn: 331100
2018-04-28 12:38:21 +08:00
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i64 %x, 0
%cmp2 = icmp slt i64 %x, 0
%select1 = select i1 %cmp2, i32 -7, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}
define i32 @compare_against_zero_type_mismatch_non_idiomatic_2(i64 %x) {
; CHECK-LABEL: @compare_against_zero_type_mismatch_non_idiomatic_2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp sgt i64 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
; CHECK: callfoo:
; CHECK-NEXT: call void @foo(i32 1)
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret i32 42
;
entry:
%cmp1 = icmp eq i64 %x, 0
%cmp2 = icmp slt i64 %x, 0
%select1 = select i1 %cmp2, i32 -6, i32 1
%select2 = select i1 %cmp1, i32 0, i32 %select1
%cond = icmp sgt i32 %select2, 0
br i1 %cond, label %callfoo, label %exit
callfoo:
call void @foo(i32 %select2)
br label %exit
exit:
ret i32 42
}