From 5d561f3ef1a05f504aae94c481483de53082975f Mon Sep 17 00:00:00 2001
From: Cary R <cygcary@yahoo.com>
Date: Sat, 9 Dec 2023 12:49:25 -0800
Subject: [PATCH] Fix time issue in FreeBSD (pow() bug)

---
 elab_sig.cc                   |  4 +--
 ivtest/ivltests/timeliteral.v | 50 ++++++++++++++++++++++++++++++++++-
 parse.y                       | 14 ++++++++++
 3 files changed, 65 insertions(+), 3 deletions(-)

diff --git a/elab_sig.cc b/elab_sig.cc
index 0c8ec6f39..68818474d 100644
--- a/elab_sig.cc
+++ b/elab_sig.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2021 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2023 Stephen Williams (steve@icarus.com)
  * Copyright CERN 2012 / Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
@@ -1189,7 +1189,7 @@ NetNet* PWire::elaborate_sig(Design*des, NetScope*scope) const
 	    cerr << get_fileline() << ": debug: Create signal " << wtype;
 	    if (set_data_type_)
 		  cout << " " << *set_data_type_;
-	    cout << name_ << unpacked_dimensions << " in scope "
+	    cout << " " << name_ << unpacked_dimensions << " in scope "
 		 << scope_path(scope) << endl;
       }
 
diff --git a/ivtest/ivltests/timeliteral.v b/ivtest/ivltests/timeliteral.v
index 219d1cda9..a08119d47 100644
--- a/ivtest/ivltests/timeliteral.v
+++ b/ivtest/ivltests/timeliteral.v
@@ -16,6 +16,8 @@ module same;
   timeunit 1ps;
   timeprecision 1ps;
 
+  logic passed;
+
   function logic check_time;
     realtime result;
 
@@ -45,12 +47,29 @@ module same;
       check_time = 1'b0;
     end
   endfunction
+
+  initial begin
+    passed = 1'b1;
+    #0.499ps;
+    if ($realtime() != 0.0) begin
+      $display("Failed: Expected a 0.499ps delay to scale to 0ps of delay, got %f", $realtime());
+      passed = 1'b0;
+    end
+
+    #0.5ps;
+    if ($realtime() != 1.0) begin
+      $display("Failed: Expected a 0.5ps delay to scale to 1ps of delay, got %f", $realtime());
+      passed = 1'b0;
+    end
+  end
 endmodule
 
 module max;
   timeunit 100s;
   timeprecision 1fs;
 
+  bit passed;
+
   function logic check_time;
     realtime result;
 
@@ -74,6 +93,21 @@ module max;
       check_time = 1'b0;
     end
   endfunction
+
+  initial begin
+    passed = 1'b1;
+    #0.499fs;
+    if ($realtime() != 0.0) begin
+      $display("Failed: Expected a 0.499fs delay to scale to 0s of delay, got %f", $realtime());
+      passed = 1'b0;
+    end
+
+    #0.5fs;
+    if ($realtime() != 1e-17) begin
+      $display("Failed: Expected a 0.5fs delay to scale to 1e-17s of delay, got %f", $realtime());
+      passed = 1'b0;
+    end
+  end
 endmodule
 
 module top;
@@ -119,6 +153,20 @@ module top;
     passed &= same.check_time();
     passed &= max.check_time();
 
-    if (passed) $display("PASSED");
+    #0.499ps;
+    if ($realtime() != 0.0) begin
+      $display("Failed: Expected a 0.499fs delay to scale to 0ns of delay, got %f", $realtime());
+      passed = 1'b0;
+    end
+
+    #0.5ps;
+    if ($realtime() != 0.001) begin
+      $display("Failed: Expected a 0.5fs delay to scale to 0.001ns of delay, got %f", $realtime());
+      passed = 1'b0;
+    end
+
+    #1; // Make sure all the delay tests have completed
+
+    if (passed && max.passed && same.passed) $display("PASSED");
   end
 endmodule
diff --git a/parse.y b/parse.y
index 66f98064c..0b9b61454 100644
--- a/parse.y
+++ b/parse.y
@@ -3178,7 +3178,14 @@ delay_value_simple
 	if ($1 == 0 || !get_time_unit($1, unit))
 	      yyerror(@1, "internal error: time literal delay.");
 	else {
+#ifdef __FreeBSD__
+		// Using raw pow() in FreeBSD gives a value that is off by one and this causes
+		// rounding issues later, so for now use powl() to get the correct result.
+	      long double ldp = powl(10.0, (long double)(unit - pform_get_timeunit()));
+	      double p = (double) ldp;
+#else
 	      double p = pow(10.0, (double)(unit - pform_get_timeunit()));
+#endif
 	      double time = atof($1) * p;
 
 	      verireal *v = new verireal(time);
@@ -3825,7 +3832,14 @@ expr_primary
         if ($1 == 0 || !get_time_unit($1, unit))
               yyerror(@1, "internal error: time literal.");
         else {
+#ifdef __FreeBSD__
+                // Using raw pow() in FreeBSD gives a value that is off by one and this causes
+                // rounding issues below, so for now use powl() to get the correct result.
+              long double ldp = powl(10.0, (double)(unit - pform_get_timeunit()));
+              double p = (double) ldp;
+#else
               double p = pow(10.0, (double)(unit - pform_get_timeunit()));
+#endif
               double time = atof($1) * p;
               // The time value needs to be rounded at the correct digit
               // since this is a normal real value and not a delay that