builtins: add signature to some assembly routines

Add a helpful description and a signature for the functions implemented in
assembly for the integral math routines.  NFC.

llvm-svn: 215296
diff --git a/compiler-rt/lib/builtins/arm/divmodsi4.S b/compiler-rt/lib/builtins/arm/divmodsi4.S
index 91bb2a5..96527f7 100644
--- a/compiler-rt/lib/builtins/arm/divmodsi4.S
+++ b/compiler-rt/lib/builtins/arm/divmodsi4.S
@@ -27,6 +27,10 @@
 	.thumb
 #endif
 
+@ int __divmodsi4(int divident, int divisor, int *remainder)
+@   Calculate the quotient and remainder of the (signed) division.  The return
+@   value is the quotient, the remainder is placed in the variable.
+
 	.p2align 3
 DEFINE_COMPILERRT_FUNCTION(__divmodsi4)
 #if __ARM_ARCH_EXT_IDIV__
diff --git a/compiler-rt/lib/builtins/arm/divsi3.S b/compiler-rt/lib/builtins/arm/divsi3.S
index db47165..73ee78d 100644
--- a/compiler-rt/lib/builtins/arm/divsi3.S
+++ b/compiler-rt/lib/builtins/arm/divsi3.S
@@ -29,6 +29,10 @@
 	.p2align 3
 // Ok, APCS and AAPCS agree on 32 bit args, so it's safe to use the same routine.
 DEFINE_AEABI_FUNCTION_ALIAS(__aeabi_idiv, __divsi3)
+
+@ int __divsi3(int divident, int divisor)
+@   Calculate and return the quotient of the (signed) division.
+
 DEFINE_COMPILERRT_FUNCTION(__divsi3)
 #if __ARM_ARCH_EXT_IDIV__
    tst     r1,r1
diff --git a/compiler-rt/lib/builtins/arm/modsi3.S b/compiler-rt/lib/builtins/arm/modsi3.S
index 7ed305e..57ffa3b 100644
--- a/compiler-rt/lib/builtins/arm/modsi3.S
+++ b/compiler-rt/lib/builtins/arm/modsi3.S
@@ -26,6 +26,9 @@
 	.thumb
 #endif
 
+@ int __modsi3(int divident, int divisor)
+@   Calculate and return the remainder of the (signed) division.
+
 	.p2align 3
 DEFINE_COMPILERRT_FUNCTION(__modsi3)
 #if __ARM_ARCH_EXT_IDIV__
diff --git a/compiler-rt/lib/builtins/arm/udivmodsi4.S b/compiler-rt/lib/builtins/arm/udivmodsi4.S
index aaece97..d04cb98 100644
--- a/compiler-rt/lib/builtins/arm/udivmodsi4.S
+++ b/compiler-rt/lib/builtins/arm/udivmodsi4.S
@@ -21,6 +21,11 @@
 	.thumb
 #endif
 
+@ unsigned int __udivmodsi4(unsigned int divident, unsigned int divisor,
+@                           unsigned int *remainder)
+@   Calculate the quotient and remainder of the (unsigned) division.  The return
+@   value is the quotient, the remainder is placed in the variable.
+
 	.p2align 2
 DEFINE_COMPILERRT_FUNCTION(__udivmodsi4)
 #if __ARM_ARCH_EXT_IDIV__
diff --git a/compiler-rt/lib/builtins/arm/udivsi3.S b/compiler-rt/lib/builtins/arm/udivsi3.S
index 34bd713..afe34e0 100644
--- a/compiler-rt/lib/builtins/arm/udivsi3.S
+++ b/compiler-rt/lib/builtins/arm/udivsi3.S
@@ -23,6 +23,10 @@
 
 	.p2align 2
 DEFINE_AEABI_FUNCTION_ALIAS(__aeabi_uidiv, __udivsi3)
+
+@ unsigned int __udivsi3(unsigned int divident, unsigned int divisor)
+@   Calculate and return the quotient of the (unsigned) division.
+
 DEFINE_COMPILERRT_FUNCTION(__udivsi3)
 #if __ARM_ARCH_EXT_IDIV__
 	tst     r1, r1
diff --git a/compiler-rt/lib/builtins/arm/umodsi3.S b/compiler-rt/lib/builtins/arm/umodsi3.S
index b0c62d7..f9327ac 100644
--- a/compiler-rt/lib/builtins/arm/umodsi3.S
+++ b/compiler-rt/lib/builtins/arm/umodsi3.S
@@ -20,6 +20,9 @@
 	.thumb
 #endif
 
+@ unsigned int __umodsi3(unsigned int divident, unsigned int divisor)
+@   Calculate and return the remainder of the (unsigned) division.
+
 	.p2align 2
 DEFINE_COMPILERRT_FUNCTION(__umodsi3)
 #if __ARM_ARCH_EXT_IDIV__