[llvm] [TableGen] Avoid warnings with INT64_MIN (PR #152996)

[Piotr Fusik via llvm-commits]

https://github.com/pfusik created https://github.com/llvm/llvm-project/pull/152996

The number 0x8000000000000000 caused:

    warning: integer constant is so large that it is unsigned

Emit the INT64_MIN macro instead of a negative literal.

Triggered in #151687

>From 3af4cbb9e2d6b38b5c469f55f65e414828ab7cb3 Mon Sep 17 00:00:00 2001
From: Piotr Fusik <p.fusik at samsung.com>
Date: Mon, 11 Aug 2025 12:36:37 +0200
Subject: [PATCH 1/2] [TableGen][test] Test INT64_MIN literals

---
 .../TableGen/GlobalISelEmitter/int64min.td    | 30 +++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 llvm/test/TableGen/GlobalISelEmitter/int64min.td

diff --git a/llvm/test/TableGen/GlobalISelEmitter/int64min.td b/llvm/test/TableGen/GlobalISelEmitter/int64min.td
new file mode 100644
index 0000000000000..01c101ebe67bd
--- /dev/null
+++ b/llvm/test/TableGen/GlobalISelEmitter/int64min.td
@@ -0,0 +1,30 @@
+// RUN: llvm-tblgen -gen-global-isel -optimize-match-table=false -I %p/../../../include -I %p/../Common %s | FileCheck %s
+
+include "llvm/Target/Target.td"
+include "GlobalISelEmitterCommon.td"
+
+def GPR : RegisterClass<"MyTarget", [i64], 64, (add R0)>;
+def ANDI : I<(outs GPR:$dst), (ins GPR:$src1, i64imm:$src2), []>;
+
+// CHECK-LABEL: GIM_Try, /*On fail goto*//*Label 0*/ GIMT_Encode4(59), // Rule ID 0 //
+// CHECK-NEXT: GIM_CheckNumOperands, /*MI*/0, /*Expected*/3,
+// CHECK-NEXT: GIM_CheckOpcode, /*MI*/0, GIMT_Encode2(TargetOpcode::G_AND),
+// CHECK-NEXT: // MIs[0] DstI[dst]
+// CHECK-NEXT: GIM_RootCheckType, /*Op*/0, /*Type*/GILLT_s64,
+// CHECK-NEXT: GIM_RootCheckRegBankForClass, /*Op*/0, /*RC*/GIMT_Encode2(MyTarget::GPRRegClassID),
+// CHECK-NEXT: // MIs[0] rs1
+// CHECK-NEXT: GIM_RootCheckType, /*Op*/1, /*Type*/GILLT_s64,
+// CHECK-NEXT: GIM_RootCheckRegBankForClass, /*Op*/1, /*RC*/GIMT_Encode2(MyTarget::GPRRegClassID),
+// CHECK-NEXT: // MIs[0] Operand 2
+// CHECK-NEXT: GIM_RootCheckType, /*Op*/2, /*Type*/GILLT_s64,
+// CHECK-NEXT: GIM_CheckConstantInt, /*MI*/0, /*Op*/2, GIMT_Encode8(-9223372036854775808),
+// CHECK-NEXT: // (and:{ *:[i64] } GPR:{ *:[i64] }:$rs1, -9223372036854775808:{ *:[i64] })  =>  (ANDI:{ *:[i64] } GPR:{ *:[i64] }:$rs1, -9223372036854775808:{ *:[i64] })
+// CHECK-NEXT: GIR_BuildRootMI, /*Opcode*/GIMT_Encode2(MyTarget::ANDI),
+// CHECK-NEXT: GIR_RootToRootCopy, /*OpIdx*/0, // DstI[dst]
+// CHECK-NEXT: GIR_RootToRootCopy, /*OpIdx*/1, // rs1
+// CHECK-NEXT: GIR_AddImm, /*InsnID*/0, /*Imm*/GIMT_Encode8(-9223372036854775808),
+// CHECK-NEXT: GIR_RootConstrainSelectedInstOperands,
+// CHECK-NEXT: // GIR_Coverage, 0,
+// CHECK-NEXT: GIR_EraseRootFromParent_Done,
+def : Pat<(and GPR:$rs1, 0x8000000000000000),
+          (ANDI GPR:$rs1, 0x8000000000000000)>;

>From 9b10b8e282dbfd156c08f2b8f6e3e314948be9f2 Mon Sep 17 00:00:00 2001
From: Piotr Fusik <p.fusik at samsung.com>
Date: Mon, 11 Aug 2025 12:49:24 +0200
Subject: [PATCH 2/2] [TableGen] Avoid warnings with INT64_MIN

The number 0x8000000000000000 caused:

    warning: integer constant is so large that it is unsigned

Emit the INT64_MIN macro instead of a negative literal.

Triggered in #151687
---
 llvm/test/TableGen/GlobalISelEmitter/int64min.td              | 4 ++--
 .../utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/llvm/test/TableGen/GlobalISelEmitter/int64min.td b/llvm/test/TableGen/GlobalISelEmitter/int64min.td
index 01c101ebe67bd..7ca4cb44318ec 100644
--- a/llvm/test/TableGen/GlobalISelEmitter/int64min.td
+++ b/llvm/test/TableGen/GlobalISelEmitter/int64min.td
@@ -17,12 +17,12 @@ def ANDI : I<(outs GPR:$dst), (ins GPR:$src1, i64imm:$src2), []>;
 // CHECK-NEXT: GIM_RootCheckRegBankForClass, /*Op*/1, /*RC*/GIMT_Encode2(MyTarget::GPRRegClassID),
 // CHECK-NEXT: // MIs[0] Operand 2
 // CHECK-NEXT: GIM_RootCheckType, /*Op*/2, /*Type*/GILLT_s64,
-// CHECK-NEXT: GIM_CheckConstantInt, /*MI*/0, /*Op*/2, GIMT_Encode8(-9223372036854775808),
+// CHECK-NEXT: GIM_CheckConstantInt, /*MI*/0, /*Op*/2, GIMT_Encode8(INT64_MIN),
 // CHECK-NEXT: // (and:{ *:[i64] } GPR:{ *:[i64] }:$rs1, -9223372036854775808:{ *:[i64] })  =>  (ANDI:{ *:[i64] } GPR:{ *:[i64] }:$rs1, -9223372036854775808:{ *:[i64] })
 // CHECK-NEXT: GIR_BuildRootMI, /*Opcode*/GIMT_Encode2(MyTarget::ANDI),
 // CHECK-NEXT: GIR_RootToRootCopy, /*OpIdx*/0, // DstI[dst]
 // CHECK-NEXT: GIR_RootToRootCopy, /*OpIdx*/1, // rs1
-// CHECK-NEXT: GIR_AddImm, /*InsnID*/0, /*Imm*/GIMT_Encode8(-9223372036854775808),
+// CHECK-NEXT: GIR_AddImm, /*InsnID*/0, /*Imm*/GIMT_Encode8(INT64_MIN),
 // CHECK-NEXT: GIR_RootConstrainSelectedInstOperands,
 // CHECK-NEXT: // GIR_Coverage, 0,
 // CHECK-NEXT: GIR_EraseRootFromParent_Done,
diff --git a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp
index 70141ba738bdb..45b896c4091cf 100644
--- a/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp
+++ b/llvm/utils/TableGen/Common/GlobalISel/GlobalISelMatchTable.cpp
@@ -237,7 +237,7 @@ MatchTableRecord MatchTable::NamedValue(unsigned NumBytes, StringRef Namespace,
 
 MatchTableRecord MatchTable::IntValue(unsigned NumBytes, int64_t IntValue) {
   assert(isUIntN(NumBytes * 8, IntValue) || isIntN(NumBytes * 8, IntValue));
-  auto Str = llvm::to_string(IntValue);
+  auto Str = IntValue == INT64_MIN ? "INT64_MIN" : llvm::to_string(IntValue);
   if (NumBytes == 1 && IntValue < 0)
     Str = "uint8_t(" + Str + ")";
   // TODO: Could optimize this directly to save the compiler some work when