[llvm] r359121 - [X86] Remove dead nodes left after ReplaceAllUsesWith calls during address matching
Craig Topper via llvm-commits
llvm-commits at lists.llvm.org
Wed Apr 24 11:02:07 PDT 2019
Author: ctopper
Date: Wed Apr 24 11:02:07 2019
New Revision: 359121
URL: http://llvm.org/viewvc/llvm-project?rev=359121&view=rev
Log:
[X86] Remove dead nodes left after ReplaceAllUsesWith calls during address matching
ReplaceAllUsesWith doesn't remove the node that was replaced. So its left around in the graph messing up use counts on other nodes.
One thing to note, is that this isn't valid if the node being deleted is the root node of an LEA match that gets rejected. In that case the node needs to stay alive because the isel table walking code would still have a reference to it that its going to try to match next. I don't think that's the case here though because the nodes being deleted here should be "and", "srl", and "zero_extend" none of which can be the root node of an LEA match.
Differential Revision: https://reviews.llvm.org/D61048
Modified:
llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp
llvm/trunk/test/CodeGen/X86/fold-and-shift.ll
llvm/trunk/test/CodeGen/X86/pr32329.ll
Modified: llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp?rev=359121&r1=359120&r2=359121&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp Wed Apr 24 11:02:07 2019
@@ -1375,6 +1375,7 @@ static bool foldMaskAndShiftToExtract(Se
insertDAGNode(DAG, N, ShlCount);
insertDAGNode(DAG, N, Shl);
DAG.ReplaceAllUsesWith(N, Shl);
+ DAG.RemoveDeadNode(N.getNode());
AM.IndexReg = And;
AM.Scale = (1 << ScaleLog);
return false;
@@ -1441,6 +1442,7 @@ static bool foldMaskedShiftToScaledMask(
insertDAGNode(DAG, N, NewAnd);
insertDAGNode(DAG, N, NewShift);
DAG.ReplaceAllUsesWith(N, NewShift);
+ DAG.RemoveDeadNode(N.getNode());
AM.Scale = 1 << ShiftAmt;
AM.IndexReg = NewAnd;
@@ -1551,6 +1553,7 @@ static bool foldMaskAndShiftToScale(Sele
insertDAGNode(DAG, N, NewSHLAmt);
insertDAGNode(DAG, N, NewSHL);
DAG.ReplaceAllUsesWith(N, NewSHL);
+ DAG.RemoveDeadNode(N.getNode());
AM.Scale = 1 << AMShiftAmt;
AM.IndexReg = NewSRL;
@@ -1609,6 +1612,7 @@ static bool foldMaskedShiftToBEXTR(Selec
insertDAGNode(DAG, N, NewSHLAmt);
insertDAGNode(DAG, N, NewSHL);
DAG.ReplaceAllUsesWith(N, NewSHL);
+ DAG.RemoveDeadNode(N.getNode());
AM.Scale = 1 << AMShiftAmt;
AM.IndexReg = NewAnd;
@@ -1940,6 +1944,7 @@ bool X86DAGToDAGISel::matchAddressRecurs
insertDAGNode(*CurDAG, N, Zext);
insertDAGNode(*CurDAG, N, NewShl);
CurDAG->ReplaceAllUsesWith(N, NewShl);
+ CurDAG->RemoveDeadNode(N.getNode());
return false;
}
}
Modified: llvm/trunk/test/CodeGen/X86/fold-and-shift.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/fold-and-shift.ll?rev=359121&r1=359120&r2=359121&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/fold-and-shift.ll (original)
+++ llvm/trunk/test/CodeGen/X86/fold-and-shift.ll Wed Apr 24 11:02:07 2019
@@ -5,8 +5,8 @@ define i32 @t1(i8* %X, i32 %i) {
; CHECK-LABEL: t1:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax
-; CHECK-NEXT: movl {{[0-9]+}}(%esp), %ecx
-; CHECK-NEXT: movzbl %cl, %ecx
+; CHECK-NEXT: movl $255, %ecx
+; CHECK-NEXT: andl {{[0-9]+}}(%esp), %ecx
; CHECK-NEXT: movl (%eax,%ecx,4), %eax
; CHECK-NEXT: retl
@@ -23,8 +23,8 @@ define i32 @t2(i16* %X, i32 %i) {
; CHECK-LABEL: t2:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax
-; CHECK-NEXT: movl {{[0-9]+}}(%esp), %ecx
-; CHECK-NEXT: movzwl %cx, %ecx
+; CHECK-NEXT: movl $65535, %ecx # imm = 0xFFFF
+; CHECK-NEXT: andl {{[0-9]+}}(%esp), %ecx
; CHECK-NEXT: movl (%eax,%ecx,4), %eax
; CHECK-NEXT: retl
@@ -111,8 +111,8 @@ define i8 @t6(i8* %X, i32 %i) {
; CHECK-LABEL: t6:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax
-; CHECK-NEXT: movl {{[0-9]+}}(%esp), %ecx
-; CHECK-NEXT: andl $-255, %ecx
+; CHECK-NEXT: movl $-255, %ecx
+; CHECK-NEXT: andl {{[0-9]+}}(%esp), %ecx
; CHECK-NEXT: movb (%eax,%ecx,4), %al
; CHECK-NEXT: retl
Modified: llvm/trunk/test/CodeGen/X86/pr32329.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/pr32329.ll?rev=359121&r1=359120&r2=359121&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/pr32329.ll (original)
+++ llvm/trunk/test/CodeGen/X86/pr32329.ll Wed Apr 24 11:02:07 2019
@@ -29,18 +29,18 @@ define void @foo() local_unnamed_addr {
; X86-NEXT: .cfi_offset %edi, -16
; X86-NEXT: .cfi_offset %ebx, -12
; X86-NEXT: .cfi_offset %ebp, -8
-; X86-NEXT: movl obj, %edx
; X86-NEXT: movsbl var_27, %eax
; X86-NEXT: movzwl var_2, %esi
; X86-NEXT: movl var_310, %ecx
; X86-NEXT: imull %eax, %ecx
; X86-NEXT: addl var_24, %ecx
-; X86-NEXT: andl $4194303, %edx # imm = 0x3FFFFF
-; X86-NEXT: leal (%edx,%edx), %ebx
-; X86-NEXT: subl %eax, %ebx
-; X86-NEXT: movl %ebx, %edi
-; X86-NEXT: subl %esi, %edi
-; X86-NEXT: imull %edi, %ecx
+; X86-NEXT: movl $4194303, %edi # imm = 0x3FFFFF
+; X86-NEXT: andl obj, %edi
+; X86-NEXT: leal (%edi,%edi), %edx
+; X86-NEXT: subl %eax, %edx
+; X86-NEXT: movl %edx, %ebx
+; X86-NEXT: subl %esi, %ebx
+; X86-NEXT: imull %ebx, %ecx
; X86-NEXT: addb $113, %cl
; X86-NEXT: movl $9, %esi
; X86-NEXT: xorl %ebp, %ebp
@@ -50,12 +50,12 @@ define void @foo() local_unnamed_addr {
; X86-NEXT: cmovnel %esi, %ebp
; X86-NEXT: movl $0, %ecx
; X86-NEXT: cmovnel %ecx, %esi
-; X86-NEXT: cmpl %edx, %edi
+; X86-NEXT: cmpl %edi, %ebx
; X86-NEXT: movl %ebp, var_50+4
; X86-NEXT: movl %esi, var_50
; X86-NEXT: setge var_205
-; X86-NEXT: imull %eax, %ebx
-; X86-NEXT: movb %bl, var_218
+; X86-NEXT: imull %eax, %edx
+; X86-NEXT: movb %dl, var_218
; X86-NEXT: popl %esi
; X86-NEXT: .cfi_def_cfa_offset 16
; X86-NEXT: popl %edi
@@ -68,24 +68,24 @@ define void @foo() local_unnamed_addr {
;
; X64-LABEL: foo:
; X64: # %bb.0: # %entry
-; X64-NEXT: movl {{.*}}(%rip), %eax
; X64-NEXT: movsbl {{.*}}(%rip), %r9d
; X64-NEXT: movzwl {{.*}}(%rip), %r8d
; X64-NEXT: movl {{.*}}(%rip), %ecx
; X64-NEXT: imull %r9d, %ecx
; X64-NEXT: addl {{.*}}(%rip), %ecx
-; X64-NEXT: andl $4194303, %eax # imm = 0x3FFFFF
-; X64-NEXT: leal (%rax,%rax), %edi
+; X64-NEXT: movl $4194303, %esi # imm = 0x3FFFFF
+; X64-NEXT: andl {{.*}}(%rip), %esi
+; X64-NEXT: leal (%rsi,%rsi), %edi
; X64-NEXT: subl %r9d, %edi
-; X64-NEXT: movl %edi, %esi
-; X64-NEXT: subl %r8d, %esi
-; X64-NEXT: imull %esi, %ecx
+; X64-NEXT: movl %edi, %edx
+; X64-NEXT: subl %r8d, %edx
+; X64-NEXT: imull %edx, %ecx
; X64-NEXT: addb $113, %cl
-; X64-NEXT: movl $9, %edx
+; X64-NEXT: movl $9, %eax
; X64-NEXT: # kill: def $cl killed $cl killed $ecx
-; X64-NEXT: shlq %cl, %rdx
-; X64-NEXT: movq %rdx, {{.*}}(%rip)
-; X64-NEXT: cmpl %eax, %esi
+; X64-NEXT: shlq %cl, %rax
+; X64-NEXT: movq %rax, {{.*}}(%rip)
+; X64-NEXT: cmpl %esi, %edx
; X64-NEXT: setge {{.*}}(%rip)
; X64-NEXT: imull %r9d, %edi
; X64-NEXT: movb %dil, {{.*}}(%rip)
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