From 36b8b48bbb22bfed546babfdb858191f79cb19e5 Mon Sep 17 00:00:00 2001
From: Saleem Abdulrasool <compnerd@compnerd.org>
Date: Fri, 16 May 2014 05:41:33 +0000
Subject: [PATCH] ARM: add some integer/floating point conversion libcalls

Add some Windows on ARM specific library calls.  These are provided by msvcrt,
and can be used to perform integer to floating-point conversions (and
vice-versa) mirroring similar functions in the RTABI.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208949 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/ARM/ARMISelLowering.cpp            | 22 ++++++
 .../integer-floating-point-conversion.ll      | 74 +++++++++++++++++++
 2 files changed, 96 insertions(+)
 create mode 100644 test/CodeGen/ARM/Windows/integer-floating-point-conversion.ll

diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index d5617dd66ee..c2d9b7a1248 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -418,6 +418,28 @@ ARMTargetLowering::ARMTargetLowering(TargetMachine &TM)
     setLibcallCallingConv(RTLIB::MEMSET, CallingConv::ARM_AAPCS);
   }
 
+  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->getTargetTriple().isiOS() &&
       !Subtarget->getTargetTriple().isOSVersionLT(5, 0)) {
diff --git a/test/CodeGen/ARM/Windows/integer-floating-point-conversion.ll b/test/CodeGen/ARM/Windows/integer-floating-point-conversion.ll
new file mode 100644
index 00000000000..acf21a1caad
--- /dev/null
+++ b/test/CodeGen/ARM/Windows/integer-floating-point-conversion.ll
@@ -0,0 +1,74 @@
+; RUN: llc -mtriple thumbv7-windows -filetype asm -o - %s | FileCheck %s
+
+define arm_aapcs_vfpcc i64 @stoi64(float %f) {
+entry:
+  %conv = fptosi float %f to i64
+  ret i64 %conv
+}
+
+; CHECK-LABEL: stoi64
+; CHECK: bl __stoi64
+
+define arm_aapcs_vfpcc i64 @stou64(float %f) {
+entry:
+  %conv = fptoui float %f to i64
+  ret i64 %conv
+}
+
+; CHECK-LABEL: stou64
+; CHECK: bl __stou64
+
+define arm_aapcs_vfpcc float @i64tos(i64 %i64) {
+entry:
+  %conv = sitofp i64 %i64 to float
+  ret float %conv
+}
+
+; CHECK-LABEL: i64tos
+; CHECK: bl __i64tos
+
+define arm_aapcs_vfpcc float @u64tos(i64 %u64) {
+entry:
+  %conv = uitofp i64 %u64 to float
+  ret float %conv
+}
+
+; CHECK-LABEL: u64tos
+; CHECK: bl __u64tos
+
+define arm_aapcs_vfpcc i64 @dtoi64(double %d) {
+entry:
+  %conv = fptosi double %d to i64
+  ret i64 %conv
+}
+
+; CHECK-LABEL: dtoi64
+; CHECK: bl __dtoi64
+
+define arm_aapcs_vfpcc i64 @dtou64(double %d) {
+entry:
+  %conv = fptoui double %d to i64
+  ret i64 %conv
+}
+
+; CHECK-LABEL: dtou64
+; CHECK: bl __dtou64
+
+define arm_aapcs_vfpcc double @i64tod(i64 %i64) {
+entry:
+  %conv = sitofp i64 %i64 to double
+  ret double %conv
+}
+
+; CHECK-LABEL: i64tod
+; CHECK: bl __i64tod
+
+define arm_aapcs_vfpcc double @u64tod(i64 %i64) {
+entry:
+  %conv = uitofp i64 %i64 to double
+  ret double %conv
+}
+
+; CHECK-LABEL: u64tod
+; CHECK: bl __u64tod
+