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[Qemu-trivial] [PATCH v2] Use proper term in TCG README
From: |
Wei-Ren Chen |
Subject: |
[Qemu-trivial] [PATCH v2] Use proper term in TCG README |
Date: |
Thu, 14 Mar 2013 16:06:46 +0800 |
User-agent: |
Mutt/1.5.21 (2010-09-15) |
In TCG, "target" means the host architecture for which TCG generates
the code. Using "guest" rather than "target" to make the document more
consistent.
Signed-off-by: Chen Wei-Ren <address@hidden>
---
tcg/README | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/tcg/README b/tcg/README
index 934e7af..00d4751 100644
--- a/tcg/README
+++ b/tcg/README
@@ -14,6 +14,9 @@ the emulated architecture. As TCG started as a generic C
backend used
for cross compiling, it is assumed that the TCG target is different
from the host, although it is never the case for QEMU.
+In this document, we uses "guest" to specify what architecture we are
+emulating, and "target" means on what machine we are running QEMU.
+
A TCG "function" corresponds to a QEMU Translated Block (TB).
A TCG "temporary" is a variable only live in a basic
@@ -379,7 +382,7 @@ double-word product T0. The later is returned in two
single-word outputs.
Similar to mulu2, except the two inputs T1 and T2 are signed.
-********* 64-bit target on 32-bit host support
+********* 64-bit guest on 32-bit host support
The following opcodes are internal to TCG. Thus they are to be implemented by
32-bit host code generators, but are not to be emitted by guest translators.
@@ -521,9 +524,9 @@ register.
a better generated code, but it reduces the memory usage of TCG and
the speed of the translation.
-- Don't hesitate to use helpers for complicated or seldom used target
+- Don't hesitate to use helpers for complicated or seldom used guest
instructions. There is little performance advantage in using TCG to
- implement target instructions taking more than about twenty TCG
+ implement guest instructions taking more than about twenty TCG
instructions. Note that this rule of thumb is more applicable to
helpers doing complex logic or arithmetic, where the C compiler has
scope to do a good job of optimisation; it is less relevant where
@@ -531,9 +534,9 @@ register.
inline TCG may still be faster for longer sequences.
- The hard limit on the number of TCG instructions you can generate
- per target instruction is set by MAX_OP_PER_INSTR in exec-all.h --
+ per guest instruction is set by MAX_OP_PER_INSTR in exec-all.h --
you cannot exceed this without risking a buffer overrun.
- Use the 'discard' instruction if you know that TCG won't be able to
prove that a given global is "dead" at a given program point. The
- x86 target uses it to improve the condition codes optimisation.
+ x86 guest uses it to improve the condition codes optimisation.
--
1.7.12.3
- [Qemu-trivial] [PATCH v2] Use proper term in TCG README,
Wei-Ren Chen <=