Revert r372285 "GlobalISel: Don't materialize immarg arguments to intrinsics"

This broke the Chromium build, causing it to fail with e.g.

  fatal error: error in backend: Cannot select: t362: v4i32 = X86ISD::VSHLI t392, Constant:i8<15>

See llvm-commits thread of r372285 for details.

This also reverts r372286, r372287, r372288, r372289, r372290, r372291,
r372292, r372293, r372296, and r372297, which seemed to depend on the
main commit.

> Encode them directly as an imm argument to G_INTRINSIC*.
>
> Since now intrinsics can now define what parameters are required to be
> immediates, avoid using registers for them. Intrinsics could
> potentially want a constant that isn't a legal register type. Also,
> since G_CONSTANT is subject to CSE and legalization, transforms could
> potentially obscure the value (and create extra work for the
> selector). The register bank of a G_CONSTANT is also meaningful, so
> this could throw off future folding and legalization logic for AMDGPU.
>
> This will be much more convenient to work with than needing to call
> getConstantVRegVal and checking if it may have failed for every
> constant intrinsic parameter. AMDGPU has quite a lot of intrinsics wth
> immarg operands, many of which need inspection during lowering. Having
> to find the value in a register is going to add a lot of boilerplate
> and waste compile time.
>
> SelectionDAG has always provided TargetConstant for constants which
> should not be legalized or materialized in a register. The distinction
> between Constant and TargetConstant was somewhat fuzzy, and there was
> no automatic way to force usage of TargetConstant for certain
> intrinsic parameters. They were both ultimately ConstantSDNode, and it
> was inconsistently used. It was quite easy to mis-select an
> instruction requiring an immediate. For SelectionDAG, start emitting
> TargetConstant for these arguments, and using timm to match them.
>
> Most of the work here is to cleanup target handling of constants. Some
> targets process intrinsics through intermediate custom nodes, which
> need to preserve TargetConstant usage to match the intrinsic
> expectation. Pattern inputs now need to distinguish whether a constant
> is merely compatible with an operand or whether it is mandatory.
>
> The GlobalISelEmitter needs to treat timm as a special case of a leaf
> node, simlar to MachineBasicBlock operands. This should also enable
> handling of patterns for some G_* instructions with immediates, like
> G_FENCE or G_EXTRACT.
>
> This does include a workaround for a crash in GlobalISelEmitter when
> ARM tries to uses "imm" in an output with a "timm" pattern source.

llvm-svn: 372314

1 files changed, 1 insertions, 26 deletions

diff --git a/llvm/utils/TableGen/GlobalISelEmitter.cpp b/llvm/utils/TableGen/GlobalISelEmitter.cpp
index d8d4c9f4f55..fbf0b4bd9dd 100644
--- a/llvm/utils/TableGen/GlobalISelEmitter.cpp
+++ b/llvm/utils/TableGen/GlobalISelEmitter.cpp
@@ -1062,7 +1062,6 @@ public:
     IPM_Opcode,
     IPM_NumOperands,
     IPM_ImmPredicate,
-    IPM_Imm,
     IPM_AtomicOrderingMMO,
     IPM_MemoryLLTSize,
     IPM_MemoryVsLLTSize,
@@ -1341,23 +1340,6 @@ public:
   }
 };
 
-class ImmOperandMatcher : public OperandPredicateMatcher {
-public:
-  ImmOperandMatcher(unsigned InsnVarID, unsigned OpIdx)
-      : OperandPredicateMatcher(IPM_Imm, InsnVarID, OpIdx) {}
-
-  static bool classof(const PredicateMatcher *P) {
-    return P->getKind() == IPM_Imm;
-  }
-
-  void emitPredicateOpcodes(MatchTable &Table,
-                            RuleMatcher &Rule) const override {
-    Table << MatchTable::Opcode("GIM_CheckIsImm") << MatchTable::Comment("MI")
-          << MatchTable::IntValue(InsnVarID) << MatchTable::Comment("Op")
-          << MatchTable::IntValue(OpIdx) << MatchTable::LineBreak;
-  }
-};
-
 /// Generates code to check that an operand is a G_CONSTANT with a particular
 /// int.
 class ConstantIntOperandMatcher : public OperandPredicateMatcher {
@@ -3812,10 +3794,6 @@ Error GlobalISelEmitter::importChildMatcher(RuleMatcher &Rule,
         OM.addPredicate<MBBOperandMatcher>();
         return Error::success();
       }
-      if (SrcChild->getOperator()->getName() == "timm") {
-        OM.addPredicate<ImmOperandMatcher>();
-        return Error::success();
-      }
     }
   }
 
@@ -3965,10 +3943,7 @@ Expected<action_iterator> GlobalISelEmitter::importExplicitUseRenderer(
     // rendered as operands.
     // FIXME: The target should be able to choose sign-extended when appropriate
     //        (e.g. on Mips).
-    if (DstChild->getOperator()->getName() == "timm") {
-      DstMIBuilder.addRenderer<CopyRenderer>(DstChild->getName());
-      return InsertPt;
-    } else if (DstChild->getOperator()->getName() == "imm") {
+    if (DstChild->getOperator()->getName() == "imm") {
       DstMIBuilder.addRenderer<CopyConstantAsImmRenderer>(DstChild->getName());
       return InsertPt;
     } else if (DstChild->getOperator()->getName() == "fpimm") {