Set ADDE/ADDC/SUBE/SUBC to expand by default

Summary:
They've been deprecated in favor of UADDO/ADDCARRY or USUBO/SUBCARRY for a while.

Target that uses these opcodes are changed in order to ensure their behavior doesn't change.

Reviewers: efriedma, craig.topper, dblaikie, bkramer

Subscribers: jholewinski, arsenm, jyknight, sdardis, nemanjai, nhaehnle, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, mgrang, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D47422

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333748 91177308-0d34-0410-b5e6-96231b3b80d8

12 files changed, 38 insertions, 59 deletions

diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index 2fb71e40c3a..3341d4ba3fe 100644
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -156,6 +156,12 @@ Changes to the C API
   interface was made a deprecated no-op in LLVM 5. Use
   ``LLVMAddSLPVectorizePass`` instead to get the supported SLP vectorizer.
 
+Changes to the DAG infrastructure
+---------------------------------
+* ADDC/ADDE/SUBC/SUBE are now deprecated and will default to expand. Backends
+  that wish to continue to use these opcodes should explicitely request so
+  using ``setOperationAction`` in their ``TargetLowering``. New backends
+  should use UADDO/ADDCARRY/USUBO/SUBCARRY instead of the deprecated opcodes.
 
 External Open Source Projects Using LLVM 7
 ==========================================
diff --git a/lib/CodeGen/TargetLoweringBase.cpp b/lib/CodeGen/TargetLoweringBase.cpp
index 3a2036b15a0..96e03388d5c 100644
--- a/lib/CodeGen/TargetLoweringBase.cpp
+++ b/lib/CodeGen/TargetLoweringBase.cpp
@@ -621,6 +621,12 @@ void TargetLoweringBase::initActions() {
     setOperationAction(ISD::SUBCARRY, VT, Expand);
     setOperationAction(ISD::SETCCCARRY, VT, Expand);
 
+    // ADDC/ADDE/SUBC/SUBE default to expand.
+    setOperationAction(ISD::ADDC, VT, Expand);
+    setOperationAction(ISD::ADDE, VT, Expand);
+    setOperationAction(ISD::SUBC, VT, Expand);
+    setOperationAction(ISD::SUBE, VT, Expand);
+
     // These default to Expand so they will be expanded to CTLZ/CTTZ by default.
     setOperationAction(ISD::CTLZ_ZERO_UNDEF, VT, Expand);
     setOperationAction(ISD::CTTZ_ZERO_UNDEF, VT, Expand);
diff --git a/lib/Target/AMDGPU/AMDGPUISelLowering.cpp b/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
index d0f12678204..bc888dad67b 100644
--- a/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
+++ b/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
@@ -391,6 +391,12 @@ AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
     setOperationAction(ISD::BSWAP, VT, Expand);
     setOperationAction(ISD::CTTZ, VT, Expand);
     setOperationAction(ISD::CTLZ, VT, Expand);
+
+    // AMDGPU uses ADDC/SUBC/ADDE/SUBE
+    setOperationAction(ISD::ADDC, VT, Legal);
+    setOperationAction(ISD::SUBC, VT, Legal);
+    setOperationAction(ISD::ADDE, VT, Legal);
+    setOperationAction(ISD::SUBE, VT, Legal);
   }
 
   if (!Subtarget->hasBCNT(32))
@@ -470,10 +476,6 @@ AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
     setOperationAction(ISD::SDIVREM, VT, Custom);
     setOperationAction(ISD::UDIVREM, VT, Expand);
-    setOperationAction(ISD::ADDC, VT, Expand);
-    setOperationAction(ISD::SUBC, VT, Expand);
-    setOperationAction(ISD::ADDE, VT, Expand);
-    setOperationAction(ISD::SUBE, VT, Expand);
     setOperationAction(ISD::SELECT, VT, Expand);
     setOperationAction(ISD::VSELECT, VT, Expand);
     setOperationAction(ISD::SELECT_CC, VT, Expand);
diff --git a/lib/Target/AMDGPU/SIISelLowering.cpp b/lib/Target/AMDGPU/SIISelLowering.cpp
index 9145e2e56dc..c33fcd6060b 100644
--- a/lib/Target/AMDGPU/SIISelLowering.cpp
+++ b/lib/Target/AMDGPU/SIISelLowering.cpp
@@ -234,9 +234,6 @@ SITargetLowering::SITargetLowering(const TargetMachine &TM,
   setOperationAction(ISD::SUBCARRY, MVT::i64, Legal);
 #endif
 
-  //setOperationAction(ISD::ADDC, MVT::i64, Expand);
-  //setOperationAction(ISD::SUBC, MVT::i64, Expand);
-
   // We only support LOAD/STORE and vector manipulation ops for vectors
   // with > 4 elements.
   for (MVT VT : {MVT::v8i32, MVT::v8f32, MVT::v16i32, MVT::v16f32,
diff --git a/lib/Target/BPF/BPFISelLowering.cpp b/lib/Target/BPF/BPFISelLowering.cpp
index e81c2f5f832..5c9f51a3924 100644
--- a/lib/Target/BPF/BPFISelLowering.cpp
+++ b/lib/Target/BPF/BPFISelLowering.cpp
@@ -88,10 +88,6 @@ BPFTargetLowering::BPFTargetLowering(const TargetMachine &TM,
     setOperationAction(ISD::MULHS, VT, Expand);
     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
-    setOperationAction(ISD::ADDC, VT, Expand);
-    setOperationAction(ISD::ADDE, VT, Expand);
-    setOperationAction(ISD::SUBC, VT, Expand);
-    setOperationAction(ISD::SUBE, VT, Expand);
     setOperationAction(ISD::ROTR, VT, Expand);
     setOperationAction(ISD::ROTL, VT, Expand);
     setOperationAction(ISD::SHL_PARTS, VT, Expand);
diff --git a/lib/Target/Hexagon/HexagonISelLowering.cpp b/lib/Target/Hexagon/HexagonISelLowering.cpp
index 2b66099588f..4a85427032c 100644
--- a/lib/Target/Hexagon/HexagonISelLowering.cpp
+++ b/lib/Target/Hexagon/HexagonISelLowering.cpp
@@ -1327,28 +1327,6 @@ HexagonTargetLowering::HexagonTargetLowering(const TargetMachine &TM,
     setMinimumJumpTableEntries(std::numeric_limits<int>::max());
   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
 
-  // Hexagon has instructions for add/sub with carry. The problem with
-  // modeling these instructions is that they produce 2 results: Rdd and Px.
-  // To model the update of Px, we will have to use Defs[p0..p3] which will
-  // cause any predicate live range to spill. So, we pretend we dont't have
-  // these instructions.
-  setOperationAction(ISD::ADDE, MVT::i8,  Expand);
-  setOperationAction(ISD::ADDE, MVT::i16, Expand);
-  setOperationAction(ISD::ADDE, MVT::i32, Expand);
-  setOperationAction(ISD::ADDE, MVT::i64, Expand);
-  setOperationAction(ISD::SUBE, MVT::i8,  Expand);
-  setOperationAction(ISD::SUBE, MVT::i16, Expand);
-  setOperationAction(ISD::SUBE, MVT::i32, Expand);
-  setOperationAction(ISD::SUBE, MVT::i64, Expand);
-  setOperationAction(ISD::ADDC, MVT::i8,  Expand);
-  setOperationAction(ISD::ADDC, MVT::i16, Expand);
-  setOperationAction(ISD::ADDC, MVT::i32, Expand);
-  setOperationAction(ISD::ADDC, MVT::i64, Expand);
-  setOperationAction(ISD::SUBC, MVT::i8,  Expand);
-  setOperationAction(ISD::SUBC, MVT::i16, Expand);
-  setOperationAction(ISD::SUBC, MVT::i32, Expand);
-  setOperationAction(ISD::SUBC, MVT::i64, Expand);
-
   // Only add and sub that detect overflow are the saturating ones.
   for (MVT VT : MVT::integer_valuetypes()) {
     setOperationAction(ISD::UADDO, VT, Expand);
@@ -1428,10 +1406,9 @@ HexagonTargetLowering::HexagonTargetLowering(const TargetMachine &TM,
   // either "custom" or "legal" for specific cases.
   static const unsigned VectExpOps[] = {
     // Integer arithmetic:
-    ISD::ADD,     ISD::SUB,     ISD::MUL,     ISD::SDIV,    ISD::UDIV,
-    ISD::SREM,    ISD::UREM,    ISD::SDIVREM, ISD::UDIVREM, ISD::ADDC,
-    ISD::SUBC,    ISD::SADDO,   ISD::UADDO,   ISD::SSUBO,   ISD::USUBO,
-    ISD::SMUL_LOHI,             ISD::UMUL_LOHI,
+    ISD::ADD,     ISD::SUB,     ISD::MUL,     ISD::SDIV,      ISD::UDIV,
+    ISD::SREM,    ISD::UREM,    ISD::SDIVREM, ISD::UDIVREM,   ISD::SADDO,
+    ISD::UADDO,   ISD::SSUBO,   ISD::USUBO,   ISD::SMUL_LOHI, ISD::UMUL_LOHI,
     // Logical/bit:
     ISD::AND,     ISD::OR,      ISD::XOR,     ISD::ROTL,    ISD::ROTR,
     ISD::CTPOP,   ISD::CTLZ,    ISD::CTTZ,
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index 834bbb9dedd..3ad3639e037 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -393,18 +393,11 @@ MipsTargetLowering::MipsTargetLowering(const MipsTargetMachine &TM,
   setOperationAction(ISD::UDIV, MVT::i64, Expand);
   setOperationAction(ISD::UREM, MVT::i64, Expand);
 
-  if (!(Subtarget.hasDSP() && Subtarget.hasMips32r2())) {
-    setOperationAction(ISD::ADDC, MVT::i32, Expand);
-    setOperationAction(ISD::ADDE, MVT::i32, Expand);
+  if (Subtarget.hasDSP() && Subtarget.hasMips32r2()) {
+    setOperationAction(ISD::ADDC, MVT::i32, Legal);
+    setOperationAction(ISD::ADDE, MVT::i32, Legal);
   }
 
-  setOperationAction(ISD::ADDC, MVT::i64, Expand);
-  setOperationAction(ISD::ADDE, MVT::i64, Expand);
-  setOperationAction(ISD::SUBC, MVT::i32, Expand);
-  setOperationAction(ISD::SUBE, MVT::i32, Expand);
-  setOperationAction(ISD::SUBC, MVT::i64, Expand);
-  setOperationAction(ISD::SUBE, MVT::i64, Expand);
-
   // Operations not directly supported by Mips.
   setOperationAction(ISD::BR_CC,             MVT::f32,   Expand);
   setOperationAction(ISD::BR_CC,             MVT::f64,   Expand);
diff --git a/lib/Target/NVPTX/NVPTXISelLowering.cpp b/lib/Target/NVPTX/NVPTXISelLowering.cpp
index d20fe468d77..19842b958a7 100644
--- a/lib/Target/NVPTX/NVPTXISelLowering.cpp
+++ b/lib/Target/NVPTX/NVPTXISelLowering.cpp
@@ -467,9 +467,6 @@ NVPTXTargetLowering::NVPTXTargetLowering(const NVPTXTargetMachine &TM,
   // TRAP can be lowered to PTX trap
   setOperationAction(ISD::TRAP, MVT::Other, Legal);
 
-  setOperationAction(ISD::ADDC, MVT::i64, Expand);
-  setOperationAction(ISD::ADDE, MVT::i64, Expand);
-
   // Register custom handling for vector loads/stores
   for (MVT VT : MVT::vector_valuetypes()) {
     if (IsPTXVectorType(VT)) {
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 1f787994d9d..b1157f2088c 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -172,6 +172,15 @@ PPCTargetLowering::PPCTargetLowering(const PPCTargetMachine &TM,
   setIndexedStoreAction(ISD::PRE_INC, MVT::f32, Legal);
   setIndexedStoreAction(ISD::PRE_INC, MVT::f64, Legal);
 
+  // PowerPC uses ADDC/ADDE/SUBC/SUBE to propagate carry.
+  const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
+  for (MVT VT : ScalarIntVTs) {
+    setOperationAction(ISD::ADDC, VT, Legal);
+    setOperationAction(ISD::ADDE, VT, Legal);
+    setOperationAction(ISD::SUBC, VT, Legal);
+    setOperationAction(ISD::SUBE, VT, Legal);
+  }
+
   if (Subtarget.useCRBits()) {
     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand);
 
diff --git a/lib/Target/RISCV/RISCVISelLowering.cpp b/lib/Target/RISCV/RISCVISelLowering.cpp
index f5726143464..9f0069878d8 100644
--- a/lib/Target/RISCV/RISCVISelLowering.cpp
+++ b/lib/Target/RISCV/RISCVISelLowering.cpp
@@ -80,11 +80,6 @@ RISCVTargetLowering::RISCVTargetLowering(const TargetMachine &TM,
   for (auto VT : {MVT::i1, MVT::i8, MVT::i16})
     setOperationAction(ISD::SIGN_EXTEND_INREG, VT, Expand);
 
-  setOperationAction(ISD::ADDC, XLenVT, Expand);
-  setOperationAction(ISD::ADDE, XLenVT, Expand);
-  setOperationAction(ISD::SUBC, XLenVT, Expand);
-  setOperationAction(ISD::SUBE, XLenVT, Expand);
-
   if (!Subtarget.hasStdExtM()) {
     setOperationAction(ISD::MUL, XLenVT, Expand);
     setOperationAction(ISD::MULHS, XLenVT, Expand);
diff --git a/lib/Target/Sparc/SparcISelLowering.cpp b/lib/Target/Sparc/SparcISelLowering.cpp
index 3b04038ffcc..34e0297fe9f 100644
--- a/lib/Target/Sparc/SparcISelLowering.cpp
+++ b/lib/Target/Sparc/SparcISelLowering.cpp
@@ -1590,6 +1590,11 @@ SparcTargetLowering::SparcTargetLowering(const TargetMachine &TM,
   setOperationAction(ISD::EH_SJLJ_SETJMP, MVT::i32, Custom);
   setOperationAction(ISD::EH_SJLJ_LONGJMP, MVT::Other, Custom);
 
+  setOperationAction(ISD::ADDC, MVT::i32, Custom);
+  setOperationAction(ISD::ADDE, MVT::i32, Custom);
+  setOperationAction(ISD::SUBC, MVT::i32, Custom);
+  setOperationAction(ISD::SUBE, MVT::i32, Custom);
+
   if (Subtarget->is64Bit()) {
     setOperationAction(ISD::ADDC, MVT::i64, Custom);
     setOperationAction(ISD::ADDE, MVT::i64, Custom);
diff --git a/lib/Target/XCore/XCoreISelLowering.cpp b/lib/Target/XCore/XCoreISelLowering.cpp
index 0ac5ecfa7e8..99e76144cba 100644
--- a/lib/Target/XCore/XCoreISelLowering.cpp
+++ b/lib/Target/XCore/XCoreISelLowering.cpp
@@ -91,10 +91,6 @@ XCoreTargetLowering::XCoreTargetLowering(const TargetMachine &TM,
   // XCore does not have the NodeTypes below.
   setOperationAction(ISD::BR_CC,     MVT::i32,   Expand);
   setOperationAction(ISD::SELECT_CC, MVT::i32,   Expand);
-  setOperationAction(ISD::ADDC, MVT::i32, Expand);
-  setOperationAction(ISD::ADDE, MVT::i32, Expand);
-  setOperationAction(ISD::SUBC, MVT::i32, Expand);
-  setOperationAction(ISD::SUBE, MVT::i32, Expand);
 
   // 64bit
   setOperationAction(ISD::ADD, MVT::i64, Custom);