[llvm-commits] CVS: llvm/lib/Target/X86/README.txt

[Chris Lattner]

Changes in directory llvm/lib/Target/X86:

README.txt updated: 1.49 -> 1.50
---
Log message:

add a simple optimization


---
Diffs of the changes:  (+16 -0)

 README.txt |   16 ++++++++++++++++
 1 files changed, 16 insertions(+)


Index: llvm/lib/Target/X86/README.txt
diff -u llvm/lib/Target/X86/README.txt:1.49 llvm/lib/Target/X86/README.txt:1.50
--- llvm/lib/Target/X86/README.txt:1.49	Wed Feb  8 01:12:07 2006
+++ llvm/lib/Target/X86/README.txt	Wed Feb  8 11:47:22 2006
@@ -411,3 +411,19 @@
     *target &= ~(1 << bit);
 }
 
+//===---------------------------------------------------------------------===//
+
+Easy: Global addresses are not always allowed as immediates.  For this:
+
+int dst = 0; int *ptr = 0;
+void foo() { ptr = &dst; }
+
+we get this:
+
+_foo:
+        movl $_dst, %eax
+        movl %eax, _ptr
+        ret
+
+When: "movl $_dst, _ptr" is sufficient.
+