[llvm-branch-commits] [llvm-branch] r333469 - Merging r332680:

[Tom Stellard via llvm-branch-commits]

Author: tstellar
Date: Tue May 29 15:38:57 2018
New Revision: 333469

URL: http://llvm.org/viewvc/llvm-project?rev=333469&view=rev
Log:
Merging r332680:

------------------------------------------------------------------------
r332680 | kfischer | 2018-05-17 17:40:52 -0700 (Thu, 17 May 2018) | 13 lines

[X86DomainReassignment] Don't delete IMPLICIT_DEF nodes

Summary:
We cannot simply delete IMPLICIT_DEF nodes. They may be used
later (e.g. by a PHI) and deleting them will cause later passes (e.g.
LiveVariables) to crash. However, it seems fine to ignore them for
purposes of the domain reassignment (as we do with PHI).

Fixes PR37430
Fixes JuliaLang/julia#27080

Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D46797
------------------------------------------------------------------------

Added:
    llvm/branches/release_60/test/CodeGen/X86/domain-reassignment-implicit-def.ll
Modified:
    llvm/branches/release_60/lib/Target/X86/X86DomainReassignment.cpp

Modified: llvm/branches/release_60/lib/Target/X86/X86DomainReassignment.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_60/lib/Target/X86/X86DomainReassignment.cpp?rev=333469&r1=333468&r2=333469&view=diff
==============================================================================
--- llvm/branches/release_60/lib/Target/X86/X86DomainReassignment.cpp (original)
+++ llvm/branches/release_60/lib/Target/X86/X86DomainReassignment.cpp Tue May 29 15:38:57 2018
@@ -262,25 +262,6 @@ public:
   }
 };
 
-/// An Instruction Converter which completely deletes an instruction.
-/// For example, IMPLICIT_DEF instructions can be deleted when converting from
-/// GPR to mask.
-class InstrDeleter : public InstrConverterBase {
-public:
-  InstrDeleter(unsigned SrcOpcode) : InstrConverterBase(SrcOpcode) {}
-
-  bool convertInstr(MachineInstr *MI, const TargetInstrInfo *TII,
-                    MachineRegisterInfo *MRI) const override {
-    assert(isLegal(MI, TII) && "Cannot convert instruction");
-    return true;
-  }
-
-  double getExtraCost(const MachineInstr *MI,
-                      MachineRegisterInfo *MRI) const override {
-    return 0;
-  }
-};
-
 // Key type to be used by the Instruction Converters map.
 // A converter is identified by <destination domain, source opcode>
 typedef std::pair<int, unsigned> InstrConverterBaseKeyTy;
@@ -587,7 +568,7 @@ void X86DomainReassignment::initConverte
       new InstrIgnore(TargetOpcode::PHI);
 
   Converters[{MaskDomain, TargetOpcode::IMPLICIT_DEF}] =
-      new InstrDeleter(TargetOpcode::IMPLICIT_DEF);
+      new InstrIgnore(TargetOpcode::IMPLICIT_DEF);
 
   Converters[{MaskDomain, TargetOpcode::INSERT_SUBREG}] =
       new InstrReplaceWithCopy(TargetOpcode::INSERT_SUBREG, 2);

Added: llvm/branches/release_60/test/CodeGen/X86/domain-reassignment-implicit-def.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_60/test/CodeGen/X86/domain-reassignment-implicit-def.ll?rev=333469&view=auto
==============================================================================
--- llvm/branches/release_60/test/CodeGen/X86/domain-reassignment-implicit-def.ll (added)
+++ llvm/branches/release_60/test/CodeGen/X86/domain-reassignment-implicit-def.ll Tue May 29 15:38:57 2018
@@ -0,0 +1,24 @@
+; RUN: llc -mcpu=skylake-avx512 -mtriple=x86_64-unknown-linux-gnu %s -o - | FileCheck %s
+
+; Check that the X86 Domain Reassignment pass doesn't drop IMPLICIT_DEF nodes,
+; which would later cause crashes (e.g. in LiveVariables) - see PR37430
+define void @domain_reassignment_implicit_def(i1 %cond, i8 *%mem, float %arg) {
+; CHECK:    vxorps %xmm1, %xmm1, %xmm1
+; CHECK:    vcmpneqss %xmm1, %xmm0, %k0
+; CHECK:    kmovb %k0, (%rsi)
+top:
+  br i1 %cond, label %L19, label %L15
+
+L15:                                              ; preds = %top
+  %tmp47 = fcmp une float 0.000000e+00, %arg
+  %tmp48 = zext i1 %tmp47 to i8
+  br label %L21
+
+L19:                                              ; preds = %top
+  br label %L21
+
+L21:                                              ; preds = %L19, %L15
+  %.sroa.0.0 = phi i8 [ undef, %L19 ], [ %tmp48, %L15 ]
+  store i8 %.sroa.0.0, i8* %mem, align 1
+  ret void
+}