[llvm] ARM: Move setting of more runtime libcalls to RuntimeLibcallInfo (PR #143826)

[Matt Arsenault via llvm-commits]

https://github.com/arsenm created https://github.com/llvm/llvm-project/pull/143826

These are the easy cases that do not really depend on the subtarget,
other than for the deceptive predicates on the subtarget class. Most
of the rest of the cases here also do not, but this is obscured by
going through helper predicates added onto the subtarget which hide
dependence on TargetOptions.

>From 0877133f17c6746c62adfdf1a4ad6408cbf3ee3f Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault at amd.com>
Date: Thu, 12 Jun 2025 12:31:38 +0900
Subject: [PATCH] ARM: Move setting of more runtime libcalls to
 RuntimeLibcallInfo

These are the easy cases that do not really depend on the subtarget,
other than for the deceptive predicates on the subtarget class. Most
of the rest of the cases here also do not, but this is obscured by
going through helper predicates added onto the subtarget which hide
dependence on TargetOptions.
---
 llvm/lib/IR/RuntimeLibcalls.cpp         | 28 +++++++++++++++++++++++
 llvm/lib/Target/ARM/ARMISelLowering.cpp | 30 -------------------------
 2 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/llvm/lib/IR/RuntimeLibcalls.cpp b/llvm/lib/IR/RuntimeLibcalls.cpp
index 31013310a746d..331b319511aed 100644
--- a/llvm/lib/IR/RuntimeLibcalls.cpp
+++ b/llvm/lib/IR/RuntimeLibcalls.cpp
@@ -79,6 +79,34 @@ static void setARMLibcallNames(RuntimeLibcallsInfo &Info, const Triple &TT) {
       }
     }
   }
+
+  if (TT.isOSWindows()) {
+    static const struct {
+      const RTLIB::Libcall Op;
+      const char *const Name;
+      const CallingConv::ID CC;
+    } LibraryCalls[] = {
+        {RTLIB::FPTOSINT_F32_I64, "__stoi64", CallingConv::ARM_AAPCS_VFP},
+        {RTLIB::FPTOSINT_F64_I64, "__dtoi64", CallingConv::ARM_AAPCS_VFP},
+        {RTLIB::FPTOUINT_F32_I64, "__stou64", CallingConv::ARM_AAPCS_VFP},
+        {RTLIB::FPTOUINT_F64_I64, "__dtou64", CallingConv::ARM_AAPCS_VFP},
+        {RTLIB::SINTTOFP_I64_F32, "__i64tos", CallingConv::ARM_AAPCS_VFP},
+        {RTLIB::SINTTOFP_I64_F64, "__i64tod", CallingConv::ARM_AAPCS_VFP},
+        {RTLIB::UINTTOFP_I64_F32, "__u64tos", CallingConv::ARM_AAPCS_VFP},
+        {RTLIB::UINTTOFP_I64_F64, "__u64tod", CallingConv::ARM_AAPCS_VFP},
+    };
+
+    for (const auto &LC : LibraryCalls) {
+      Info.setLibcallName(LC.Op, LC.Name);
+      Info.setLibcallCallingConv(LC.Op, LC.CC);
+    }
+  }
+
+  // Use divmod compiler-rt calls for iOS 5.0 and later.
+  if (TT.isOSBinFormatMachO() && (!TT.isiOS() || !TT.isOSVersionLT(5, 0))) {
+    Info.setLibcallName(RTLIB::SDIVREM_I32, "__divmodsi4");
+    Info.setLibcallName(RTLIB::UDIVREM_I32, "__udivmodsi4");
+  }
 }
 
 static void setMSP430Libcalls(RuntimeLibcallsInfo &Info, const Triple &TT) {
diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
index 8455eef9bad32..d2e910a248f23 100644
--- a/llvm/lib/Target/ARM/ARMISelLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -708,36 +708,6 @@ ARMTargetLowering::ARMTargetLowering(const TargetMachine &TM,
     }
   }
 
-  if (Subtarget->isTargetWindows()) {
-    static const struct {
-      const RTLIB::Libcall Op;
-      const char * const Name;
-      const CallingConv::ID CC;
-    } LibraryCalls[] = {
-      { RTLIB::FPTOSINT_F32_I64, "__stoi64", CallingConv::ARM_AAPCS_VFP },
-      { RTLIB::FPTOSINT_F64_I64, "__dtoi64", CallingConv::ARM_AAPCS_VFP },
-      { RTLIB::FPTOUINT_F32_I64, "__stou64", CallingConv::ARM_AAPCS_VFP },
-      { RTLIB::FPTOUINT_F64_I64, "__dtou64", CallingConv::ARM_AAPCS_VFP },
-      { RTLIB::SINTTOFP_I64_F32, "__i64tos", CallingConv::ARM_AAPCS_VFP },
-      { RTLIB::SINTTOFP_I64_F64, "__i64tod", CallingConv::ARM_AAPCS_VFP },
-      { RTLIB::UINTTOFP_I64_F32, "__u64tos", CallingConv::ARM_AAPCS_VFP },
-      { RTLIB::UINTTOFP_I64_F64, "__u64tod", CallingConv::ARM_AAPCS_VFP },
-    };
-
-    for (const auto &LC : LibraryCalls) {
-      setLibcallName(LC.Op, LC.Name);
-      setLibcallCallingConv(LC.Op, LC.CC);
-    }
-  }
-
-  // Use divmod compiler-rt calls for iOS 5.0 and later.
-  if (Subtarget->isTargetMachO() &&
-      !(Subtarget->isTargetIOS() &&
-        Subtarget->getTargetTriple().isOSVersionLT(5, 0))) {
-    setLibcallName(RTLIB::SDIVREM_I32, "__divmodsi4");
-    setLibcallName(RTLIB::UDIVREM_I32, "__udivmodsi4");
-  }
-
   // The half <-> float conversion functions are always soft-float on
   // non-watchos platforms, but are needed for some targets which use a
   // hard-float calling convention by default.