diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/Makefile | 2 | ||||
| -rw-r--r-- | doc/il.txt | 10 |
2 files changed, 6 insertions, 6 deletions
diff --git a/doc/Makefile b/doc/Makefile index 60129d6..6fc15e4 100644 --- a/doc/Makefile +++ b/doc/Makefile @@ -14,7 +14,7 @@ html/%.html: %.txt mkdir html 2> /dev/null || true ( echo '<!doctype html>'; \ echo '<meta name=viewport content="width=device-width, initial-scale=1">'; \ - echo '<link rel="stylesheet" href="http://c9x.me/css/simple.css" type="text/css" />'; \ + echo '<link rel="stylesheet" href="/css/simple.css" type="text/css" />'; \ echo '<link rel="stylesheet" href="txt.css" type="text/css" />'; \ sed -ne '2{s,.*,<title>&</title>,;p;q}' $<; \ echo '<div class="container">'; \ diff --git a/doc/il.txt b/doc/il.txt index 51525d7..865b81f 100644 --- a/doc/il.txt +++ b/doc/il.txt @@ -761,7 +761,7 @@ will be correctly compiled by QBE. @end ret %s -Now, if you want to know what a phi instruction is and how +Now, if you want to know what phi instructions are and how to use them in QBE, you can read the following. Phi instructions are specific to SSA form. In SSA form @@ -791,10 +791,10 @@ translate it in SSA form is to insert a phi instruction. %y =w phi @ift 1, @iff 2 ret %y -The phi in the example expresses a choice depending on -which block the control came from. When the `@ift` block -is taken, the phi instruction defining `%y` selects 1; -if `@iff` is taken, 2 is selected. +Phi instructions return one of their arguments depending +on where the control came from. In the example, `%y` is +set to 1 if the `@ift` branch is taken, and it is set to +2 otherwise. An important remark about phi instructions is that QBE assumes that if a variable is defined by a phi it respects |