From: Roman Lebedev <lebedev.ri@gmail.com>
Date: Sat, 18 Jul 2020 14:30:42 +0000 (+0300)
Subject: [NFC][CVP] Add tests for possible sdiv->udiv where operands are not non-negative
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7b16fd8a2514287765cdcdb09b9059d5d9a2933a;p=platform%2Fupstream%2Fllvm.git

[NFC][CVP] Add tests for possible sdiv->udiv where operands are not non-negative

Currently that fold requires both operands to be non-negative,
but the only real requirement for the fold is that we must know
the domains of the operands.
---

diff --git a/llvm/test/Transforms/CorrelatedValuePropagation/sdiv.ll b/llvm/test/Transforms/CorrelatedValuePropagation/sdiv.ll
index b037bfa..ec5de00 100644
--- a/llvm/test/Transforms/CorrelatedValuePropagation/sdiv.ll
+++ b/llvm/test/Transforms/CorrelatedValuePropagation/sdiv.ll
@@ -1,7 +1,22 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt < %s -correlated-propagation -S | FileCheck %s
 
-; CHECK-LABEL: @test0(
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+
 define void @test0(i32 %n) {
+; CHECK-LABEL: @test0(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[FOR_COND:%.*]]
+; CHECK:       for.cond:
+; CHECK-NEXT:    [[J_0:%.*]] = phi i32 [ [[N:%.*]], [[ENTRY:%.*]] ], [ [[DIV1:%.*]], [[FOR_BODY:%.*]] ]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[J_0]], 1
+; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[FOR_END:%.*]]
+; CHECK:       for.body:
+; CHECK-NEXT:    [[DIV1]] = udiv i32 [[J_0]], 2
+; CHECK-NEXT:    br label [[FOR_COND]]
+; CHECK:       for.end:
+; CHECK-NEXT:    ret void
+;
 entry:
   br label %for.cond
 
@@ -11,7 +26,6 @@ for.cond:                                         ; preds = %for.body, %entry
   br i1 %cmp, label %for.body, label %for.end
 
 for.body:                                         ; preds = %for.cond
-; CHECK: %div1 = udiv i32 %j.0, 2
   %div = sdiv i32 %j.0, 2
   br label %for.cond
 
@@ -19,8 +33,20 @@ for.end:                                          ; preds = %for.cond
   ret void
 }
 
-; CHECK-LABEL: @test1(
 define void @test1(i32 %n) {
+; CHECK-LABEL: @test1(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[FOR_COND:%.*]]
+; CHECK:       for.cond:
+; CHECK-NEXT:    [[J_0:%.*]] = phi i32 [ [[N:%.*]], [[ENTRY:%.*]] ], [ [[DIV:%.*]], [[FOR_BODY:%.*]] ]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[J_0]], -2
+; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY]], label [[FOR_END:%.*]]
+; CHECK:       for.body:
+; CHECK-NEXT:    [[DIV]] = sdiv i32 [[J_0]], 2
+; CHECK-NEXT:    br label [[FOR_COND]]
+; CHECK:       for.end:
+; CHECK-NEXT:    ret void
+;
 entry:
   br label %for.cond
 
@@ -30,7 +56,6 @@ for.cond:                                         ; preds = %for.body, %entry
   br i1 %cmp, label %for.body, label %for.end
 
 for.body:                                         ; preds = %for.cond
-; CHECK: %div = sdiv i32 %j.0, 2
   %div = sdiv i32 %j.0, 2
   br label %for.cond
 
@@ -38,14 +63,22 @@ for.end:                                          ; preds = %for.cond
   ret void
 }
 
-; CHECK-LABEL: @test2(
 define void @test2(i32 %n) {
+; CHECK-LABEL: @test2(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[N:%.*]], 1
+; CHECK-NEXT:    br i1 [[CMP]], label [[BB:%.*]], label [[EXIT:%.*]]
+; CHECK:       bb:
+; CHECK-NEXT:    [[DIV1:%.*]] = udiv i32 [[N]], 2
+; CHECK-NEXT:    br label [[EXIT]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
 entry:
   %cmp = icmp sgt i32 %n, 1
   br i1 %cmp, label %bb, label %exit
 
 bb:
-; CHECK: %div1 = udiv i32 %n, 2 
   %div = sdiv i32 %n, 2
   br label %exit
 
@@ -57,14 +90,25 @@ exit:
 ; at the point of sdiv, we know that %a is always greater than 0,
 ; because of the guard before it, so we can transform it to udiv.
 declare void @llvm.experimental.guard(i1,...)
-; CHECK-LABEL: @test4
 define void @test4(i32 %n) {
+; CHECK-LABEL: @test4(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[N:%.*]], 0
+; CHECK-NEXT:    br i1 [[CMP]], label [[LOOP:%.*]], label [[EXIT:%.*]]
+; CHECK:       loop:
+; CHECK-NEXT:    [[A:%.*]] = phi i32 [ [[N]], [[ENTRY:%.*]] ], [ [[DIV1:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[A]], 4
+; CHECK-NEXT:    call void (i1, ...) @llvm.experimental.guard(i1 [[COND]]) [ "deopt"() ]
+; CHECK-NEXT:    [[DIV1]] = udiv i32 [[A]], 6
+; CHECK-NEXT:    br i1 [[COND]], label [[LOOP]], label [[EXIT]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
 entry:
   %cmp = icmp sgt i32 %n, 0
   br i1 %cmp, label %loop, label %exit
 
 loop:
-; CHECK: udiv i32 %a, 6
   %a = phi i32 [ %n, %entry ], [ %div, %loop ]
   %cond = icmp sgt i32 %a, 4
   call void(i1,...) @llvm.experimental.guard(i1 %cond) [ "deopt"() ]
@@ -77,14 +121,26 @@ exit:
 
 ; same test as above with assume instead of guard.
 declare void @llvm.assume(i1)
-; CHECK-LABEL: @test5
 define void @test5(i32 %n) {
+; CHECK-LABEL: @test5(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[N:%.*]], 0
+; CHECK-NEXT:    br i1 [[CMP]], label [[LOOP:%.*]], label [[EXIT:%.*]]
+; CHECK:       loop:
+; CHECK-NEXT:    [[A:%.*]] = phi i32 [ [[N]], [[ENTRY:%.*]] ], [ [[DIV1:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[A]], 4
+; CHECK-NEXT:    call void @llvm.assume(i1 [[COND]])
+; CHECK-NEXT:    [[DIV1]] = udiv i32 [[A]], 6
+; CHECK-NEXT:    [[LOOPCOND:%.*]] = icmp sgt i32 [[DIV1]], 8
+; CHECK-NEXT:    br i1 [[LOOPCOND]], label [[LOOP]], label [[EXIT]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
 entry:
   %cmp = icmp sgt i32 %n, 0
   br i1 %cmp, label %loop, label %exit
 
 loop:
-; CHECK: udiv i32 %a, 6
   %a = phi i32 [ %n, %entry ], [ %div, %loop ]
   %cond = icmp sgt i32 %a, 4
   call void @llvm.assume(i1 %cond)
@@ -95,3 +151,100 @@ loop:
 exit:
   ret void
 }
+
+; Now, let's try various domain combinations for operands.
+
+define i32 @test6_pos_pos(i32 %x, i32 %y) {
+; CHECK-LABEL: @test6_pos_pos(
+; CHECK-NEXT:    [[C0:%.*]] = icmp sge i32 [[X:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C0]])
+; CHECK-NEXT:    [[C1:%.*]] = icmp sge i32 [[Y:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C1]])
+; CHECK-NEXT:    [[DIV1:%.*]] = udiv i32 [[X]], [[Y]]
+; CHECK-NEXT:    ret i32 [[DIV1]]
+;
+  %c0 = icmp sge i32 %x, 0
+  call void @llvm.assume(i1 %c0)
+  %c1 = icmp sge i32 %y, 0
+  call void @llvm.assume(i1 %c1)
+
+  %div = sdiv i32 %x, %y
+  ret i32 %div
+}
+define i32 @test7_pos_neg(i32 %x, i32 %y) {
+; CHECK-LABEL: @test7_pos_neg(
+; CHECK-NEXT:    [[C0:%.*]] = icmp sge i32 [[X:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C0]])
+; CHECK-NEXT:    [[C1:%.*]] = icmp sle i32 [[Y:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C1]])
+; CHECK-NEXT:    [[DIV:%.*]] = sdiv i32 [[X]], [[Y]]
+; CHECK-NEXT:    ret i32 [[DIV]]
+;
+  %c0 = icmp sge i32 %x, 0
+  call void @llvm.assume(i1 %c0)
+  %c1 = icmp sle i32 %y, 0
+  call void @llvm.assume(i1 %c1)
+
+  %div = sdiv i32 %x, %y
+  ret i32 %div
+}
+define i32 @test8_neg_pos(i32 %x, i32 %y) {
+; CHECK-LABEL: @test8_neg_pos(
+; CHECK-NEXT:    [[C0:%.*]] = icmp sle i32 [[X:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C0]])
+; CHECK-NEXT:    [[C1:%.*]] = icmp sge i32 [[Y:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C1]])
+; CHECK-NEXT:    [[DIV:%.*]] = sdiv i32 [[X]], [[Y]]
+; CHECK-NEXT:    ret i32 [[DIV]]
+;
+  %c0 = icmp sle i32 %x, 0
+  call void @llvm.assume(i1 %c0)
+  %c1 = icmp sge i32 %y, 0
+  call void @llvm.assume(i1 %c1)
+
+  %div = sdiv i32 %x, %y
+  ret i32 %div
+}
+define i32 @test9_neg_neg(i32 %x, i32 %y) {
+; CHECK-LABEL: @test9_neg_neg(
+; CHECK-NEXT:    [[C0:%.*]] = icmp sle i32 [[X:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C0]])
+; CHECK-NEXT:    [[C1:%.*]] = icmp sle i32 [[Y:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C1]])
+; CHECK-NEXT:    [[DIV:%.*]] = sdiv i32 [[X]], [[Y]]
+; CHECK-NEXT:    ret i32 [[DIV]]
+;
+  %c0 = icmp sle i32 %x, 0
+  call void @llvm.assume(i1 %c0)
+  %c1 = icmp sle i32 %y, 0
+  call void @llvm.assume(i1 %c1)
+
+  %div = sdiv i32 %x, %y
+  ret i32 %div
+}
+
+; After making division unsigned, can we narrow it?
+define i32 @test10_narrow(i32 %x, i32 %y) {
+; CHECK-LABEL: @test10_narrow(
+; CHECK-NEXT:    [[C0:%.*]] = icmp ult i32 [[X:%.*]], 128
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C0]])
+; CHECK-NEXT:    [[C1:%.*]] = icmp ult i32 [[Y:%.*]], 128
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C1]])
+; CHECK-NEXT:    br label [[END:%.*]]
+; CHECK:       end:
+; CHECK-NEXT:    [[DIV1_LHS_TRUNC:%.*]] = trunc i32 [[X]] to i8
+; CHECK-NEXT:    [[DIV1_RHS_TRUNC:%.*]] = trunc i32 [[Y]] to i8
+; CHECK-NEXT:    [[DIV12:%.*]] = udiv i8 [[DIV1_LHS_TRUNC]], [[DIV1_RHS_TRUNC]]
+; CHECK-NEXT:    [[DIV1_ZEXT:%.*]] = zext i8 [[DIV12]] to i32
+; CHECK-NEXT:    ret i32 [[DIV1_ZEXT]]
+;
+  %c0 = icmp ult i32 %x, 128
+  call void @llvm.assume(i1 %c0)
+  %c1 = icmp ult i32 %y, 128
+  call void @llvm.assume(i1 %c1)
+  br label %end
+
+end:
+  %div = sdiv i32 %x, %y
+  ret i32 %div
+}