From 7b16fd8a2514287765cdcdb09b9059d5d9a2933a Mon Sep 17 00:00:00 2001 From: Roman Lebedev Date: Sat, 18 Jul 2020 17:30:42 +0300 Subject: [PATCH] [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. --- .../CorrelatedValuePropagation/sdiv.ll | 173 +++++++++++++++++- 1 file changed, 163 insertions(+), 10 deletions(-) diff --git a/llvm/test/Transforms/CorrelatedValuePropagation/sdiv.ll b/llvm/test/Transforms/CorrelatedValuePropagation/sdiv.ll index b037bfaee7a21..ec5de0010a14f 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 +}