Add patch for #27080

deps/llvm.mk

@@ -488,6 +488,7 @@ $(eval $(call LLVM_PATCH,llvm-D45008)) # remove for 7.0
 $(eval $(call LLVM_PATCH,llvm-D45070)) # remove for 7.0
 $(eval $(call LLVM_PATCH,llvm-6.0.0-ifconv-D45819)) # remove for 7.0
 $(eval $(call LLVM_PATCH,llvm-D46460))
+$(eval $(call LLVM_PATCH,llvm-D46797-domain-reassign-implicit-def))
 endif # LLVM_VER
 
 # Remove hardcoded OS X requirements in compilter-rt cmake build

deps/patches/llvm-D46797-domain-reassign-implicit-def.patch

@@ -0,0 +1,91 @@
+commit e159b36b285d8bc4ebb03172f4bbfec6be26cae3
+Author: Keno Fischer <[email protected]>
+Date:   Sat May 12 19:31:34 2018 -0400
+
+    [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
+
+    Reviewers: craig.topper, guyblank
+
+    Subscribers: llvm-commits
+
+    Differential Revision: https://reviews.llvm.org/D46797
+
+diff --git a/lib/Target/X86/X86DomainReassignment.cpp b/lib/Target/X86/X86DomainReassignment.cpp
+index b41640f7bd7..f48d3ce2227 100644
+--- a/lib/Target/X86/X86DomainReassignment.cpp
++++ b/lib/Target/X86/X86DomainReassignment.cpp
+@@ -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::initConverters() {
+       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);
+diff --git a/test/CodeGen/X86/domain-reassignment-implicit-def.ll b/test/CodeGen/X86/domain-reassignment-implicit-def.ll
+new file mode 100644
+index 00000000000..aa43a2ac766
+--- /dev/null
++++ b/test/CodeGen/X86/domain-reassignment-implicit-def.ll
+@@ -0,0 +1,25 @@
++; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
++; 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
++}