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

[Chris Lattner]

Changes in directory llvm/lib/Target/X86:

README.txt updated: 1.154 -> 1.155
---
Log message:

add a note


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Diffs of the changes:  (+29 -0)

 README.txt |   29 +++++++++++++++++++++++++++++
 1 files changed, 29 insertions(+)


Index: llvm/lib/Target/X86/README.txt
diff -u llvm/lib/Target/X86/README.txt:1.154 llvm/lib/Target/X86/README.txt:1.155
--- llvm/lib/Target/X86/README.txt:1.154	Thu Feb  8 17:53:38 2007
+++ llvm/lib/Target/X86/README.txt	Mon Feb 12 14:26:34 2007
@@ -868,3 +868,32 @@
 
 //===---------------------------------------------------------------------===//
 
+This code:
+
+void test(int X) {
+  if (X) abort();
+}
+
+is currently compiled to (with -static):
+
+_test:
+        subl $12, %esp
+        cmpl $0, 16(%esp)
+        jne LBB1_1      #cond_true
+        addl $12, %esp
+        ret
+LBB1_1: #cond_true
+        call L_abort$stub
+
+It would be better to produce:
+
+_test:
+        subl $12, %esp
+        cmpl $0, 16(%esp)
+        jne L_abort$stub
+        addl $12, %esp
+        ret
+
+This can be applied to any no-return function call that takes no arguments etc.
+
+//===---------------------------------------------------------------------===//