<div dir="ltr">Why was it reverted?<div><br clear="all"><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature">~Craig</div></div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Sep 1, 2022 at 4:11 AM Nuno Lopes via llvm-commits <<a href="mailto:llvm-commits@lists.llvm.org">llvm-commits@lists.llvm.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br>
Author: Nuno Lopes<br>
Date: 2022-09-01T12:11:22+01:00<br>
New Revision: fa154a9170573e3a17639d0f71b5bccade8f7be9<br>
<br>
URL: <a href="https://github.com/llvm/llvm-project/commit/fa154a9170573e3a17639d0f71b5bccade8f7be9" rel="noreferrer" target="_blank">https://github.com/llvm/llvm-project/commit/fa154a9170573e3a17639d0f71b5bccade8f7be9</a><br>
DIFF: <a href="https://github.com/llvm/llvm-project/commit/fa154a9170573e3a17639d0f71b5bccade8f7be9.diff" rel="noreferrer" target="_blank">https://github.com/llvm/llvm-project/commit/fa154a9170573e3a17639d0f71b5bccade8f7be9.diff</a><br>
<br>
LOG: Revert "Expand Div/Rem: consider the case where the dividend is zero"<br>
<br>
This reverts commit 4aed09868b5a51a29aade11d9d412c3313310f29.<br>
<br>
Added: <br>
<br>
<br>
Modified: <br>
llvm/lib/Transforms/Utils/IntegerDivision.cpp<br>
llvm/test/Transforms/ExpandLargeDivRem/sdiv129.ll<br>
llvm/test/Transforms/ExpandLargeDivRem/srem129.ll<br>
llvm/test/Transforms/ExpandLargeDivRem/udiv129.ll<br>
llvm/test/Transforms/ExpandLargeDivRem/urem129.ll<br>
<br>
Removed: <br>
<br>
<br>
<br>
################################################################################<br>
diff --git a/llvm/lib/Transforms/Utils/IntegerDivision.cpp b/llvm/lib/Transforms/Utils/IntegerDivision.cpp<br>
index 52a175b4c87c8..1267360b34b18 100644<br>
--- a/llvm/lib/Transforms/Utils/IntegerDivision.cpp<br>
+++ b/llvm/lib/Transforms/Utils/IntegerDivision.cpp<br>
@@ -148,7 +148,6 @@ static Value *generateUnsignedDivisionCode(Value *Dividend, Value *Divisor,<br>
ConstantInt *MSB = ConstantInt::get(DivTy, BitWidth - 1);<br>
<br>
ConstantInt *True = Builder.getTrue();<br>
- ConstantInt *False = Builder.getFalse();<br>
<br>
BasicBlock *IBB = Builder.GetInsertBlock();<br>
Function *F = IBB->getParent();<br>
@@ -212,8 +211,8 @@ static Value *generateUnsignedDivisionCode(Value *Dividend, Value *Divisor,<br>
// ; %ret0_2 = icmp eq i32 %dividend, 0<br>
// ; %ret0_3 = or i1 %ret0_1, %ret0_2<br>
// ; %tmp0 = tail call i32 @llvm.ctlz.i32(i32 %divisor, i1 true)<br>
- // ; %tmp1 = tail call i32 @llvm.ctlz.i32(i32 %dividend, i1 false)<br>
- // ; %sr = sub i32 %tmp0, %tmp1<br>
+ // ; %tmp1 = tail call i32 @llvm.ctlz.i32(i32 %dividend, i1 true)<br>
+ // ; %sr = sub nsw i32 %tmp0, %tmp1<br>
// ; %ret0_4 = icmp ugt i32 %sr, 31<br>
// ; %ret0 = or i1 %ret0_3, %ret0_4<br>
// ; %retDividend = icmp eq i32 %sr, 31<br>
@@ -225,7 +224,7 @@ static Value *generateUnsignedDivisionCode(Value *Dividend, Value *Divisor,<br>
Value *Ret0_2 = Builder.CreateICmpEQ(Dividend, Zero);<br>
Value *Ret0_3 = Builder.CreateOr(Ret0_1, Ret0_2);<br>
Value *Tmp0 = Builder.CreateCall(CTLZ, {Divisor, True});<br>
- Value *Tmp1 = Builder.CreateCall(CTLZ, {Dividend, False});<br>
+ Value *Tmp1 = Builder.CreateCall(CTLZ, {Dividend, True});<br>
Value *SR = Builder.CreateSub(Tmp0, Tmp1);<br>
Value *Ret0_4 = Builder.CreateICmpUGT(SR, MSB);<br>
Value *Ret0 = Builder.CreateOr(Ret0_3, Ret0_4);<br>
<br>
diff --git a/llvm/test/Transforms/ExpandLargeDivRem/sdiv129.ll b/llvm/test/Transforms/ExpandLargeDivRem/sdiv129.ll<br>
index 2bfad7b6fa839..27ab1e8eb9ed6 100644<br>
--- a/llvm/test/Transforms/ExpandLargeDivRem/sdiv129.ll<br>
+++ b/llvm/test/Transforms/ExpandLargeDivRem/sdiv129.ll<br>
@@ -12,7 +12,7 @@ define void @sdiv129(i129* %ptr, i129* %out) nounwind {<br>
; CHECK-NEXT: [[TMP4:%.*]] = icmp eq i129 [[TMP2]], 0<br>
; CHECK-NEXT: [[TMP5:%.*]] = or i1 false, [[TMP4]]<br>
; CHECK-NEXT: [[TMP6:%.*]] = call i129 @llvm.ctlz.i129(i129 3, i1 true)<br>
-; CHECK-NEXT: [[TMP7:%.*]] = call i129 @llvm.ctlz.i129(i129 [[TMP2]], i1 false)<br>
+; CHECK-NEXT: [[TMP7:%.*]] = call i129 @llvm.ctlz.i129(i129 [[TMP2]], i1 true)<br>
; CHECK-NEXT: [[TMP8:%.*]] = sub i129 [[TMP6]], [[TMP7]]<br>
; CHECK-NEXT: [[TMP9:%.*]] = icmp ugt i129 [[TMP8]], 128<br>
; CHECK-NEXT: [[TMP10:%.*]] = or i1 [[TMP5]], [[TMP9]]<br>
<br>
diff --git a/llvm/test/Transforms/ExpandLargeDivRem/srem129.ll b/llvm/test/Transforms/ExpandLargeDivRem/srem129.ll<br>
index c4326333786fe..08df750a13663 100644<br>
--- a/llvm/test/Transforms/ExpandLargeDivRem/srem129.ll<br>
+++ b/llvm/test/Transforms/ExpandLargeDivRem/srem129.ll<br>
@@ -11,7 +11,7 @@ define void @test(i129* %ptr, i129* %out) nounwind {<br>
; CHECK-NEXT: [[TMP3:%.*]] = icmp eq i129 [[TMP2]], 0<br>
; CHECK-NEXT: [[TMP4:%.*]] = or i1 false, [[TMP3]]<br>
; CHECK-NEXT: [[TMP5:%.*]] = call i129 @llvm.ctlz.i129(i129 3, i1 true)<br>
-; CHECK-NEXT: [[TMP6:%.*]] = call i129 @llvm.ctlz.i129(i129 [[TMP2]], i1 false)<br>
+; CHECK-NEXT: [[TMP6:%.*]] = call i129 @llvm.ctlz.i129(i129 [[TMP2]], i1 true)<br>
; CHECK-NEXT: [[TMP7:%.*]] = sub i129 [[TMP5]], [[TMP6]]<br>
; CHECK-NEXT: [[TMP8:%.*]] = icmp ugt i129 [[TMP7]], 128<br>
; CHECK-NEXT: [[TMP9:%.*]] = or i1 [[TMP4]], [[TMP8]]<br>
<br>
diff --git a/llvm/test/Transforms/ExpandLargeDivRem/udiv129.ll b/llvm/test/Transforms/ExpandLargeDivRem/udiv129.ll<br>
index 1929963331913..31705a9a35c10 100644<br>
--- a/llvm/test/Transforms/ExpandLargeDivRem/udiv129.ll<br>
+++ b/llvm/test/Transforms/ExpandLargeDivRem/udiv129.ll<br>
@@ -8,7 +8,7 @@ define void @test(i129* %ptr, i129* %out) nounwind {<br>
; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i129 [[A]], 0<br>
; CHECK-NEXT: [[TMP1:%.*]] = or i1 false, [[TMP0]]<br>
; CHECK-NEXT: [[TMP2:%.*]] = call i129 @llvm.ctlz.i129(i129 3, i1 true)<br>
-; CHECK-NEXT: [[TMP3:%.*]] = call i129 @llvm.ctlz.i129(i129 [[A]], i1 false)<br>
+; CHECK-NEXT: [[TMP3:%.*]] = call i129 @llvm.ctlz.i129(i129 [[A]], i1 true)<br>
; CHECK-NEXT: [[TMP4:%.*]] = sub i129 [[TMP2]], [[TMP3]]<br>
; CHECK-NEXT: [[TMP5:%.*]] = icmp ugt i129 [[TMP4]], 128<br>
; CHECK-NEXT: [[TMP6:%.*]] = or i1 [[TMP1]], [[TMP5]]<br>
<br>
diff --git a/llvm/test/Transforms/ExpandLargeDivRem/urem129.ll b/llvm/test/Transforms/ExpandLargeDivRem/urem129.ll<br>
index 36ecb990e52f5..4e91eef6d2aa6 100644<br>
--- a/llvm/test/Transforms/ExpandLargeDivRem/urem129.ll<br>
+++ b/llvm/test/Transforms/ExpandLargeDivRem/urem129.ll<br>
@@ -8,7 +8,7 @@ define void @test(i129* %ptr, i129* %out) nounwind {<br>
; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i129 [[A]], 0<br>
; CHECK-NEXT: [[TMP1:%.*]] = or i1 false, [[TMP0]]<br>
; CHECK-NEXT: [[TMP2:%.*]] = call i129 @llvm.ctlz.i129(i129 3, i1 true)<br>
-; CHECK-NEXT: [[TMP3:%.*]] = call i129 @llvm.ctlz.i129(i129 [[A]], i1 false)<br>
+; CHECK-NEXT: [[TMP3:%.*]] = call i129 @llvm.ctlz.i129(i129 [[A]], i1 true)<br>
; CHECK-NEXT: [[TMP4:%.*]] = sub i129 [[TMP2]], [[TMP3]]<br>
; CHECK-NEXT: [[TMP5:%.*]] = icmp ugt i129 [[TMP4]], 128<br>
; CHECK-NEXT: [[TMP6:%.*]] = or i1 [[TMP1]], [[TMP5]]<br>
<br>
<br>
<br>
_______________________________________________<br>
llvm-commits mailing list<br>
<a href="mailto:llvm-commits@lists.llvm.org" target="_blank">llvm-commits@lists.llvm.org</a><br>
<a href="https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits" rel="noreferrer" target="_blank">https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits</a><br>
</blockquote></div>