[llvm-branch-commits] [llvm-branch] r344804 - Merging r343443:

[Tom Stellard via llvm-branch-commits]

Author: tstellar
Date: Fri Oct 19 12:11:17 2018
New Revision: 344804

URL: http://llvm.org/viewvc/llvm-project?rev=344804&view=rev
Log:
Merging r343443:

------------------------------------------------------------------------
r343443 | ctopper | 2018-10-01 00:08:41 -0700 (Mon, 01 Oct 2018) | 9 lines

[X86] Stop X86DomainReassignment from creating copies between GR8/GR16 physical registers and k-registers.

We can only copy between a k-register and a GR32/GR64 register.

This patch detects that the copy will be illegal and prevents the domain reassignment from happening for that closure.

This probably isn't the best fix, and we should probably figure out how to handle this correctly.

Fixes PR38803.
------------------------------------------------------------------------

Added:
    llvm/branches/release_70/test/CodeGen/X86/pr38803.ll
Modified:
    llvm/branches/release_70/lib/Target/X86/X86DomainReassignment.cpp

Modified: llvm/branches/release_70/lib/Target/X86/X86DomainReassignment.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_70/lib/Target/X86/X86DomainReassignment.cpp?rev=344804&r1=344803&r2=344804&view=diff
==============================================================================
--- llvm/branches/release_70/lib/Target/X86/X86DomainReassignment.cpp (original)
+++ llvm/branches/release_70/lib/Target/X86/X86DomainReassignment.cpp Fri Oct 19 12:11:17 2018
@@ -217,6 +217,27 @@ public:
   InstrCOPYReplacer(unsigned SrcOpcode, RegDomain DstDomain, unsigned DstOpcode)
       : InstrReplacer(SrcOpcode, DstOpcode), DstDomain(DstDomain) {}
 
+  bool isLegal(const MachineInstr *MI,
+               const TargetInstrInfo *TII) const override {
+    if (!InstrConverterBase::isLegal(MI, TII))
+      return false;
+
+    // Don't allow copies to/flow GR8/GR16 physical registers.
+    // FIXME: Is there some better way to support this?
+    unsigned DstReg = MI->getOperand(0).getReg();
+    if (TargetRegisterInfo::isPhysicalRegister(DstReg) &&
+        (X86::GR8RegClass.contains(DstReg) ||
+         X86::GR16RegClass.contains(DstReg)))
+      return false;
+    unsigned SrcReg = MI->getOperand(1).getReg();
+    if (TargetRegisterInfo::isPhysicalRegister(SrcReg) &&
+        (X86::GR8RegClass.contains(SrcReg) ||
+         X86::GR16RegClass.contains(SrcReg)))
+      return false;
+
+    return true;
+  }
+
   double getExtraCost(const MachineInstr *MI,
                       MachineRegisterInfo *MRI) const override {
     assert(MI->getOpcode() == TargetOpcode::COPY && "Expected a COPY");

Added: llvm/branches/release_70/test/CodeGen/X86/pr38803.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_70/test/CodeGen/X86/pr38803.ll?rev=344804&view=auto
==============================================================================
--- llvm/branches/release_70/test/CodeGen/X86/pr38803.ll (added)
+++ llvm/branches/release_70/test/CodeGen/X86/pr38803.ll Fri Oct 19 12:11:17 2018
@@ -0,0 +1,48 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mcpu=skylake-avx512 -mtriple=x86_64-unknown-unknown | FileCheck %s
+
+ at b = local_unnamed_addr global i32 0, align 4
+ at c = local_unnamed_addr global i32 0, align 4
+ at d = local_unnamed_addr global float 0.000000e+00, align 4
+
+define float @_Z3fn2v() {
+; CHECK-LABEL: _Z3fn2v:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    pushq %rax
+; CHECK-NEXT:    .cfi_def_cfa_offset 16
+; CHECK-NEXT:    callq _Z1av
+; CHECK-NEXT:    # kill: def $al killed $al def $eax
+; CHECK-NEXT:    kmovd %eax, %k1
+; CHECK-NEXT:    vmovss {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-NEXT:    vmovss %xmm0, %xmm0, %xmm0 {%k1} {z}
+; CHECK-NEXT:    cmpl $0, {{.*}}(%rip)
+; CHECK-NEXT:    je .LBB0_2
+; CHECK-NEXT:  # %bb.1: # %if.then
+; CHECK-NEXT:    vcvtsi2ssl {{.*}}(%rip), %xmm1, %xmm1
+; CHECK-NEXT:    kmovd %eax, %k1
+; CHECK-NEXT:    vxorps %xmm2, %xmm2, %xmm2
+; CHECK-NEXT:    vmovss %xmm2, %xmm0, %xmm1 {%k1}
+; CHECK-NEXT:    vmovss %xmm1, {{.*}}(%rip)
+; CHECK-NEXT:  .LBB0_2: # %if.end
+; CHECK-NEXT:    popq %rax
+; CHECK-NEXT:    .cfi_def_cfa_offset 8
+; CHECK-NEXT:    retq
+entry:
+  %call = tail call zeroext i1 @_Z1av()
+  %cond = select i1 %call, float 7.500000e-01, float 0.000000e+00
+  %0 = load i32, i32* @c, align 4
+  %tobool2 = icmp eq i32 %0, 0
+  br i1 %tobool2, label %if.end, label %if.then
+
+if.then:                                          ; preds = %entry
+  %1 = load i32, i32* @b, align 4
+  %2 = sitofp i32 %1 to float
+  %conv5 = select i1 %call, float 0.000000e+00, float %2
+  store float %conv5, float* @d, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %entry, %if.then
+  ret float %cond
+}
+
+declare zeroext i1 @_Z1av()