From af139b3f0a5c65969da65b2c77cd294245d7086a Mon Sep 17 00:00:00 2001
From: belliash <belliash@codingworkshop.eu.org>
Date: Wed, 15 Aug 2018 17:26:26 +0200
Subject: [PATCH] Reimplement C-like min() and max() functions. These functions
 should have C-like implementation and take exactly 2 arguments: integer or
 float. Finally, C-implementation will be faster than using PH7 builtin
 library that needs to be compiled and interpreted.

---
 engine/vm.c         | 64 ---------------------------------------------
 modules/math/math.c | 64 +++++++++++++++++++++++++++++++++++++++++++++
 modules/math/math.h |  6 ++++-
 3 files changed, 69 insertions(+), 65 deletions(-)

diff --git a/engine/vm.c b/engine/vm.c
index 559e8ab..d7df441 100644
--- a/engine/vm.c
+++ b/engine/vm.c
@@ -1089,70 +1089,6 @@ static sxi32 VmEvalChunk(ph7_vm *pVm, ph7_context *pCtx, SyString *pChunk, int i
 	"}"\
 	" return $ret;"\
 	"}"\
-	"function max(){"\
-	"  $pArgs = func_get_args();"\
-	" if( sizeof($pArgs) < 1 ){"\
-	"  return null;"\
-	" }"\
-	" if( sizeof($pArgs) < 2 ){"\
-	" $pArg = $pArgs[0];"\
-	" if( !is_array($pArg) ){"\
-	"   return $pArg; "\
-	" }"\
-	" if( sizeof($pArg) < 1 ){"\
-	"   return null;"\
-	" }"\
-	" $pArg = array_copy($pArgs[0]);"\
-	" reset($pArg);"\
-	" $max = current($pArg);"\
-	" while( FALSE !== ($val = next($pArg)) ){"\
-	"   if( $val > $max ){"\
-	"     $max = $val;"\
-	" }"\
-	" }"\
-	" return $max;"\
-	" }"\
-	" $max = $pArgs[0];"\
-	" for( $i = 1; $i < sizeof($pArgs) ; ++$i ){"\
-	" $val = $pArgs[$i];"\
-	"if( $val > $max ){"\
-	" $max = $val;"\
-	"}"\
-	" }"\
-	" return $max;"\
-	"}"\
-	"function min(){"\
-	"  $pArgs = func_get_args();"\
-	" if( sizeof($pArgs) < 1 ){"\
-	"  return null;"\
-	" }"\
-	" if( sizeof($pArgs) < 2 ){"\
-	" $pArg = $pArgs[0];"\
-	" if( !is_array($pArg) ){"\
-	"   return $pArg; "\
-	" }"\
-	" if( sizeof($pArg) < 1 ){"\
-	"   return null;"\
-	" }"\
-	" $pArg = array_copy($pArgs[0]);"\
-	" reset($pArg);"\
-	" $min = current($pArg);"\
-	" while( FALSE !== ($val = next($pArg)) ){"\
-	"   if( $val < $min ){"\
-	"     $min = $val;"\
-	" }"\
-	" }"\
-	" return $min;"\
-	" }"\
-	" $min = $pArgs[0];"\
-	" for( $i = 1; $i < sizeof($pArgs) ; ++$i ){"\
-	" $val = $pArgs[$i];"\
-	"if( $val < $min ){"\
-	" $min = $val;"\
-	" }"\
-	" }"\
-	" return $min;"\
-	"}"\
 	"function fileowner(string $file){"\
 	" $a = stat($file);"\
 	" if( !is_array($a) ){"\
diff --git a/modules/math/math.c b/modules/math/math.c
index 0425323..53f6ea3 100644
--- a/modules/math/math.c
+++ b/modules/math/math.c
@@ -624,6 +624,70 @@ static int PH7_builtin_hypot(ph7_context *pCtx, int nArg, ph7_value **apArg) {
 	ph7_result_double(pCtx, r);
 	return PH7_OK;
 }
+/*
+ * float/int64 max(float/int64 $arg )
+ *  Absolute value.
+ * Parameter
+ *  The number to process.
+ * Return
+ *  The absolute value of number.
+ */
+static int PH7_builtin_max(ph7_context *pCtx, int nArg, ph7_value **apArg) {
+	if(nArg < 2) {
+		/* Missing argument,return 0 */
+		ph7_result_int(pCtx, 0);
+		return PH7_OK;
+	}
+	if(ph7_value_is_float(apArg[0]) && ph7_value_is_float(apArg[1])) {
+		double a, b;
+		a = ph7_value_to_double(apArg[0]);
+		b = ph7_value_to_double(apArg[1]);
+		/* Perform the requested operation */
+		ph7_result_double(pCtx, SXMAX(a, b));
+	} else if(ph7_value_is_int(apArg[0]) && ph7_value_is_int(apArg[1])) {
+		sxi64 a, b;
+		a = ph7_value_to_int64(apArg[0]);
+		b = ph7_value_to_int64(apArg[1]);
+		/* Perform the requested operation */
+		ph7_result_int64(pCtx, SXMAX(a, b));
+	} else {
+		/* Two parameters of different type */
+		ph7_result_int(pCtx, 0);
+	}
+	return PH7_OK;
+}
+/*
+ * float/int64 min(float/int64 $arg )
+ *  Absolute value.
+ * Parameter
+ *  The number to process.
+ * Return
+ *  The absolute value of number.
+ */
+static int PH7_builtin_min(ph7_context *pCtx, int nArg, ph7_value **apArg) {
+	if(nArg < 2) {
+		/* Missing argument,return 0 */
+		ph7_result_int(pCtx, 0);
+		return PH7_OK;
+	}
+	if(ph7_value_is_float(apArg[0]) && ph7_value_is_float(apArg[1])) {
+		double a, b;
+		a = ph7_value_to_double(apArg[0]);
+		b = ph7_value_to_double(apArg[1]);
+		/* Perform the requested operation */
+		ph7_result_double(pCtx, SXMIN(a, b));
+	} else if(ph7_value_is_int(apArg[0]) && ph7_value_is_int(apArg[1])) {
+		sxi64 a, b;
+		a = ph7_value_to_int64(apArg[0]);
+		b = ph7_value_to_int64(apArg[1]);
+		/* Perform the requested operation */
+		ph7_result_int64(pCtx, SXMIN(a, b));
+	} else {
+		/* Two parameters of different type */
+		ph7_result_int(pCtx, 0);
+	}
+	return PH7_OK;
+}
 
 PH7_PRIVATE sxi32 initializeModule(ph7_vm *pVm, ph7_real *ver, SyString *desc) {
 	sxi32 rc;
diff --git a/modules/math/math.h b/modules/math/math.h
index 59be2fe..8a5e2dd 100644
--- a/modules/math/math.h
+++ b/modules/math/math.h
@@ -51,6 +51,8 @@ static int PH7_builtin_pow(ph7_context *pCtx, int nArg, ph7_value **apArg);
 static int PH7_builtin_pi(ph7_context *pCtx, int nArg, ph7_value **apArg);
 static int PH7_builtin_fmod(ph7_context *pCtx, int nArg, ph7_value **apArg);
 static int PH7_builtin_hypot(ph7_context *pCtx, int nArg, ph7_value **apArg);
+static int PH7_builtin_max(ph7_context *pCtx, int nArg, ph7_value **apArg);
+static int PH7_builtin_min(ph7_context *pCtx, int nArg, ph7_value **apArg);
 PH7_PRIVATE sxi32 initializeModule(ph7_vm *pVm, ph7_real *ver, SyString *desc);
 
 static const ph7_builtin_constant mathConstList[] = {
@@ -94,7 +96,9 @@ static const ph7_builtin_func mathFuncList[] = {
 	{ "pow",    PH7_builtin_pow          },
 	{ "pi",       PH7_builtin_pi           },
 	{ "fmod",     PH7_builtin_fmod         },
-	{ "hypot",    PH7_builtin_hypot        }
+	{ "hypot",    PH7_builtin_hypot        },
+	{ "max",      PH7_builtin_max          },
+	{ "min",      PH7_builtin_min          }
 };
 
 #endif