[NFC][compiler-rt] Factor out __mulv[sdt]i3 implementations to .inc file

[atrosinenko]

Summary

The existing implementations are almost identical except for width of the integer type.

Factor them out to int_mulv_impl.inc for better maintainability.

The following command may help understanding the changes:

diff int_mulv_impl.inc \
     <(git show master:./mulvsi3.c | sed 's/si_int/fixint_t/g')

The si and di variants has three lines different (with two of them being comments) and ti has a bit larger diff.

[MaskRay]

compiler-rt/lib/builtins/int_mulv_impl.inc

1

---*- C++ -*-===//

[atrosinenko]

Explicitly mark .inc file as a C source like is already done for almost all *_impl.inc files.

[atrosinenko]

compiler-rt/lib/builtins/int_mulv_impl.inc

1

Thanks. It really is a C source (there are no C++ sources in the builtins library, as far as I know), still almost all other .inc files in this directory are actually marked with -*- C -*-, so explicitly marked this one as well.

Interestingly, int_div_impl.inc is the only one such file explicitly marked as C++, but it is probably a mistake.

[MaskRay]

LGTM, but let's give others a chance to comment.

[atrosinenko]

Uploaded because it was already approved and no other review comments received since then. Anyway, please feel free to request followup changes if needed.

compiler-rt/lib/builtins/int_mulv_impl.inc

-//===-- mulvdi3.c - Implement __mulvdi3 -----------------------------------===//
+//===-- int_mulv_impl.inc - Implement __mulv[sdt]i3 ---------------*- C -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
-// This file implements __mulvdi3 for the compiler_rt library.
+// Helper used by __mulvsi3, __mulvdi3 and __mulvti3.
 //
 //===----------------------------------------------------------------------===//
 
 #include "int_lib.h"
 
 // Returns: a * b
 
 // Effects: aborts if a * b overflows
 
-COMPILER_RT_ABI di_int __mulvdi3(di_int a, di_int b) {
-  const int N = (int)(sizeof(di_int) * CHAR_BIT);
-  const di_int MIN = (di_int)1 << (N - 1);
-  const di_int MAX = ~MIN;
+static __inline fixint_t __mulvXi3(fixint_t a, fixint_t b) {
+  const int N = (int)(sizeof(fixint_t) * CHAR_BIT);
+  const fixint_t MIN = (fixint_t)1 << (N - 1);
+  const fixint_t MAX = ~MIN;
   if (a == MIN) {
     if (b == 0 || b == 1)
       return a * b;
     compilerrt_abort();
   }
   if (b == MIN) {
     if (a == 0 || a == 1)
       return a * b;
     compilerrt_abort();
   }
-  di_int sa = a >> (N - 1);
-  di_int abs_a = (a ^ sa) - sa;
-  di_int sb = b >> (N - 1);
-  di_int abs_b = (b ^ sb) - sb;
+  fixint_t sa = a >> (N - 1);
+  fixint_t abs_a = (a ^ sa) - sa;
+  fixint_t sb = b >> (N - 1);
+  fixint_t abs_b = (b ^ sb) - sb;
   if (abs_a < 2 || abs_b < 2)
     return a * b;
   if (sa == sb) {
     if (abs_a > MAX / abs_b)
       compilerrt_abort();
   } else {
     if (abs_a > MIN / -abs_b)
       compilerrt_abort();
   }
   return a * b;
 }

compiler-rt/lib/builtins/mulvdi3.c

 //===-- mulvdi3.c - Implement __mulvdi3 -----------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements __mulvdi3 for the compiler_rt library.
 //
 //===----------------------------------------------------------------------===//
 
-#include "int_lib.h"
+#define fixint_t di_int
+#include "int_mulv_impl.inc"
 
 // Returns: a * b
 
 // Effects: aborts if a * b overflows
 
-COMPILER_RT_ABI di_int __mulvdi3(di_int a, di_int b) {
-  const int N = (int)(sizeof(di_int) * CHAR_BIT);
-  const di_int MIN = (di_int)1 << (N - 1);
-  const di_int MAX = ~MIN;
-  if (a == MIN) {
-    if (b == 0 || b == 1)
-      return a * b;
-    compilerrt_abort();
-  }
-  if (b == MIN) {
-    if (a == 0 || a == 1)
-      return a * b;
-    compilerrt_abort();
-  }
-  di_int sa = a >> (N - 1);
-  di_int abs_a = (a ^ sa) - sa;
-  di_int sb = b >> (N - 1);
-  di_int abs_b = (b ^ sb) - sb;
-  if (abs_a < 2 || abs_b < 2)
-    return a * b;
-  if (sa == sb) {
-    if (abs_a > MAX / abs_b)
-      compilerrt_abort();
-  } else {
-    if (abs_a > MIN / -abs_b)
-      compilerrt_abort();
-  }
-  return a * b;
-}
+COMPILER_RT_ABI di_int __mulvdi3(di_int a, di_int b) { return __mulvXi3(a, b); }

compiler-rt/lib/builtins/mulvsi3.c

 //===-- mulvsi3.c - Implement __mulvsi3 -----------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements __mulvsi3 for the compiler_rt library.
 //
 //===----------------------------------------------------------------------===//
 
-#include "int_lib.h"
+#define fixint_t si_int
+#include "int_mulv_impl.inc"
 
 // Returns: a * b
 
 // Effects: aborts if a * b overflows
 
-COMPILER_RT_ABI si_int __mulvsi3(si_int a, si_int b) {
-  const int N = (int)(sizeof(si_int) * CHAR_BIT);
-  const si_int MIN = (si_int)1 << (N - 1);
-  const si_int MAX = ~MIN;
-  if (a == MIN) {
-    if (b == 0 || b == 1)
-      return a * b;
-    compilerrt_abort();
-  }
-  if (b == MIN) {
-    if (a == 0 || a == 1)
-      return a * b;
-    compilerrt_abort();
-  }
-  si_int sa = a >> (N - 1);
-  si_int abs_a = (a ^ sa) - sa;
-  si_int sb = b >> (N - 1);
-  si_int abs_b = (b ^ sb) - sb;
-  if (abs_a < 2 || abs_b < 2)
-    return a * b;
-  if (sa == sb) {
-    if (abs_a > MAX / abs_b)
-      compilerrt_abort();
-  } else {
-    if (abs_a > MIN / -abs_b)
-      compilerrt_abort();
-  }
-  return a * b;
-}
+COMPILER_RT_ABI si_int __mulvsi3(si_int a, si_int b) { return __mulvXi3(a, b); }

compiler-rt/lib/builtins/mulvti3.c

 #include "int_lib.h"
 
 #ifdef CRT_HAS_128BIT
 
 // Returns: a * b
 
 // Effects: aborts if a * b overflows
 
-COMPILER_RT_ABI ti_int __mulvti3(ti_int a, ti_int b) {
-  const int N = (int)(sizeof(ti_int) * CHAR_BIT);
-  const ti_int MIN = (ti_int)1 << (N - 1);
-  const ti_int MAX = ~MIN;
-  if (a == MIN) {
-    if (b == 0 || b == 1)
-      return a * b;
-    compilerrt_abort();
-  }
-  if (b == MIN) {
-    if (a == 0 || a == 1)
-      return a * b;
-    compilerrt_abort();
-  }
-  ti_int sa = a >> (N - 1);
-  ti_int abs_a = (a ^ sa) - sa;
-  ti_int sb = b >> (N - 1);
-  ti_int abs_b = (b ^ sb) - sb;
-  if (abs_a < 2 || abs_b < 2)
-    return a * b;
-  if (sa == sb) {
-    if (abs_a > MAX / abs_b)
-      compilerrt_abort();
-  } else {
-    if (abs_a > MIN / -abs_b)
-      compilerrt_abort();
-  }
-  return a * b;
-}
+#define fixint_t ti_int
+#include "int_mulv_impl.inc"
+
+COMPILER_RT_ABI ti_int __mulvti3(ti_int a, ti_int b) { return __mulvXi3(a, b); }
 
 #endif // CRT_HAS_128BIT