From 33fa211b8497b5f8d3b9511e4c29ef8d888873e5 Mon Sep 17 00:00:00 2001
From: florian <florian@freepascal.org>
Date: Tue, 17 Dec 2019 21:54:47 +0000
Subject: [PATCH]   + x86-64: assembler implementation for u128_div_u64_to_u64
 for SysV ABI   * reminder => remainder (thanks to Stefan Kanthak for pointing
 it out)

git-svn-id: trunk@43695 -
---
 rtl/inc/flt_core.inc  |  6 ++++--
 rtl/x86_64/x86_64.inc | 30 ++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/rtl/inc/flt_core.inc b/rtl/inc/flt_core.inc
index eae3950f96..d1911835bc 100644
--- a/rtl/inc/flt_core.inc
+++ b/rtl/inc/flt_core.inc
@@ -1276,6 +1276,7 @@ begin
 end;
 
 {$if defined(VALREAL_80) or defined(VALREAL_128)}
+{$ifndef FPC_SYSTEM_HAS_U128_DIV_U64_TO_U64}
 (*-------------------------------------------------------
  | u128_div_u64_to_u64 [local]
  |
@@ -1286,7 +1287,7 @@ end;
  | 128-bit integer into two 64-bit ones before converting it to ASCII.
  |
  *-------------------------------------------------------*)
-function u128_div_u64_to_u64( const xh, xl: qword; const y: qword; out quotient, reminder: qword ): boolean;
+function u128_div_u64_to_u64( const xh, xl: qword; const y: qword; out quotient, remainder: qword ): boolean;
 var
     b,                // Number base
     v,                // Norm. divisor
@@ -1342,10 +1343,11 @@ begin
             break;
     end;
     // Result
-    reminder := ( un21 * b + un0 - q0 * v ) shr s;
+    remainder := ( un21 * b + un0 - q0 * v ) shr s;
     quotient := q1 * b + q0;
     u128_div_u64_to_u64 := true;
 end;
+{$endif FPC_SYSTEM_HAS_U128_DIV_U64_TO_U64}
 {$endif VALREAL_80 | VALREAL_128}
 
 (*-------------------------------------------------------
diff --git a/rtl/x86_64/x86_64.inc b/rtl/x86_64/x86_64.inc
index c66783f9ba..a8edf06bc3 100644
--- a/rtl/x86_64/x86_64.inc
+++ b/rtl/x86_64/x86_64.inc
@@ -1073,3 +1073,33 @@ asm
 {$endif win64}
   bswap %rax
 end;
+
+
+{$ifndef win64}
+{$define FPC_SYSTEM_HAS_U128_DIV_U64_TO_U64}
+function u128_div_u64_to_u64( const xh, xl: qword; const y: qword; out quotient, remainder: qword ): boolean;nostackframe;assembler;
+{
+  SysV:
+  xh: RDI
+  xl: RSI
+  y: RDX
+  quotient: RCX
+  remainder: R8
+}
+label
+  dodiv;
+asm
+  cmpq %rdi,%rdx
+  ja   dodiv
+  xorl %eax,%eax
+  ret
+dodiv:
+  movq %rdx,%r9
+  movq %rsi,%rax
+  movq %rdi,%rdx
+  divq %r9
+  movq %rax,(%rcx)
+  movq %rdx,(%r8)
+  movl $1,%eax
+end;
+{$endif win64}