From 03a592f18ba57d52a65e70ad5e1dd709cdcfb71d Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault@amd.com>
Date: Thu, 16 Jan 2020 10:47:13 -0500
Subject: [PATCH] TableGen/GlobalISel: Fix srcvalue inputs

Allow using srcvalue for discarding pattern inputs.
---
 .../TableGen/GlobalISelEmitter-input-discard.td    | 32 ++++++++++++++++++++++
 llvm/utils/TableGen/GlobalISelEmitter.cpp          |  4 +++
 2 files changed, 36 insertions(+)
 create mode 100644 llvm/test/TableGen/GlobalISelEmitter-input-discard.td

diff --git a/llvm/test/TableGen/GlobalISelEmitter-input-discard.td b/llvm/test/TableGen/GlobalISelEmitter-input-discard.td
new file mode 100644
index 0000000..d8de1ab
--- /dev/null
+++ b/llvm/test/TableGen/GlobalISelEmitter-input-discard.td
@@ -0,0 +1,32 @@
+// RUN: llvm-tblgen -gen-global-isel -warn-on-skipped-patterns -I %p/../../include -I %p/Common %s -o - < %s | FileCheck -check-prefix=GISEL %s
+
+include "llvm/Target/Target.td"
+include "GlobalISelEmitterCommon.td"
+
+def int_tgt_foo : Intrinsic<[llvm_i32_ty], [llvm_i32_ty, llvm_i32_ty], []>;
+
+// Test that using srcvalue works for discarded pattern inputs.
+def FOO : I<(outs GPR32:$dst), (ins GPR32Op:$src0, GPR32Op:$src1), []>;
+
+// GISEL: GIM_CheckOpcode, /*MI*/0, TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS,
+// GISEL-NEXT: GIM_CheckNumOperands, /*MI*/0, /*Expected*/4,
+// GISEL-NEXT: GIM_CheckIntrinsicID, /*MI*/0, /*Op*/1, Intrinsic::tgt_foo,
+// GISEL-NEXT: GIM_CheckType, /*MI*/0, /*Op*/0, /*Type*/GILLT_s32,
+// GISEL-NEXT: GIM_CheckType, /*MI*/0, /*Op*/2, /*Type*/GILLT_s32,
+// GISEL-NEXT: GIM_CheckType, /*MI*/0, /*Op*/3, /*Type*/GILLT_s32,
+// GISEL-NEXT: GIM_CheckRegBankForClass, /*MI*/0, /*Op*/0, /*RC*/MyTarget::GPR32RegClassID,
+// GISEL-NEXT: // (intrinsic_w_chain:{ *:[i32] } 248:{ *:[iPTR] }, srcvalue:{ *:[i32] }, i32:{ *:[i32] }:$src1)  =>  (FOO:{ *:[i32] } (IMPLICIT_DEF:{ *:[i32] }), GPR32:{ *:[i32] }:$src1)
+// GISEL-NEXT: GIR_MakeTempReg, /*TempRegID*/0, /*TypeID*/GILLT_s32,
+// GISEL-NEXT: GIR_BuildMI, /*InsnID*/1, /*Opcode*/TargetOpcode::IMPLICIT_DEF,
+// GISEL-NEXT: GIR_AddTempRegister, /*InsnID*/1, /*TempRegID*/0, /*TempRegFlags*/RegState::Define,
+// GISEL-NEXT: GIR_ConstrainSelectedInstOperands, /*InsnID*/1,
+// GISEL-NEXT: GIR_BuildMI, /*InsnID*/0, /*Opcode*/MyTarget::FOO,
+// GISEL-NEXT: GIR_Copy, /*NewInsnID*/0, /*OldInsnID*/0, /*OpIdx*/0, // dst
+// GISEL-NEXT: GIR_AddTempRegister, /*InsnID*/0, /*TempRegID*/0, /*TempRegFlags*/0,
+// GISEL-NEXT: GIR_Copy, /*NewInsnID*/0, /*OldInsnID*/0, /*OpIdx*/3, // src1
+// GISEL-NEXT: GIR_EraseFromParent, /*InsnID*/0,
+// GISEL-NEXT: GIR_ConstrainSelectedInstOperands, /*InsnID*/0,
+def : Pat <
+  (int_tgt_foo (i32 srcvalue), i32:$src1),
+  (FOO (IMPLICIT_DEF), GPR32:$src1)
+>;
diff --git a/llvm/utils/TableGen/GlobalISelEmitter.cpp b/llvm/utils/TableGen/GlobalISelEmitter.cpp
index 2e5cd95..842711bf 100644
--- a/llvm/utils/TableGen/GlobalISelEmitter.cpp
+++ b/llvm/utils/TableGen/GlobalISelEmitter.cpp
@@ -3971,6 +3971,10 @@ Error GlobalISelEmitter::importChildMatcher(
           "Src pattern child def is an unsupported tablegen class (ImmLeaf)");
     }
 
+    // Place holder for SRCVALUE nodes. Nothing to do here.
+    if (ChildRec->getName() == "srcvalue")
+      return Error::success();
+
     return failedImport(
         "Src pattern child def is an unsupported tablegen class");
   }
-- 
2.7.4