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| author | Tristan Gingold <tgingold@free.fr> | 2021-08-28 10:17:22 +0200 |
|---|---|---|
| committer | Tristan Gingold <tgingold@free.fr> | 2021-08-28 13:22:30 +0200 |
| commit | c6ff96cb67935a59fe78f692974cfa5870b5f1d3 (patch) | |
| tree | 8e0102687aa12eae585bd47d693e468860abda1e /src | |
| parent | 7f05e691acbf37a5ec8b2cbd30c023368db86505 (diff) | |
| download | ghdl-c6ff96cb67935a59fe78f692974cfa5870b5f1d3.tar.gz ghdl-c6ff96cb67935a59fe78f692974cfa5870b5f1d3.tar.bz2 ghdl-c6ff96cb67935a59fe78f692974cfa5870b5f1d3.zip | |
synth-vhdl_decls.adb: add comments
Diffstat (limited to 'src')
| -rw-r--r-- | src/synth/synth-vhdl_decls.adb | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/synth/synth-vhdl_decls.adb b/src/synth/synth-vhdl_decls.adb index 779c802c1..c6ada6dba 100644 --- a/src/synth/synth-vhdl_decls.adb +++ b/src/synth/synth-vhdl_decls.adb @@ -1123,6 +1123,7 @@ package body Synth.Vhdl_Decls is raise Internal_Error; end case; if Drv = No_Net then + -- Undriven signals. if Is_Connected (Get_Output (Gate, 0)) then -- No warning if the signal is not used. -- TODO: maybe simply remove it. @@ -1135,9 +1136,12 @@ package body Synth.Vhdl_Decls is end if; end if; if Def_Val = No_Net then + -- The initial value of an undriven signal is X. Def_Val := Build_Const_X (Get_Build (Syn_Inst), Get_Width (Gate_Net)); end if; + + -- The value of an undriven signal is its initial value. Connect (Get_Input (Gate, 0), Def_Val); end if; |