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

[Chris Lattner]

Changes in directory llvm/lib/Target:

README.txt updated: 1.58 -> 1.59
---
Log message:

add a bad case evan though of.


---
Diffs of the changes:  (+32 -0)

 README.txt |   32 ++++++++++++++++++++++++++++++++
 1 files changed, 32 insertions(+)


Index: llvm/lib/Target/README.txt
diff -u llvm/lib/Target/README.txt:1.58 llvm/lib/Target/README.txt:1.59
--- llvm/lib/Target/README.txt:1.58	Sun Mar 18 17:41:33 2007
+++ llvm/lib/Target/README.txt	Sat Mar 24 01:01:32 2007
@@ -377,3 +377,35 @@
 regs and bswap, like itanium.
 
 //===---------------------------------------------------------------------===//
+
+LSR should know what GPR types a target has.  This code:
+
+volatile short X, Y; // globals
+
+void foo(int N) {
+  int i;
+  for (i = 0; i < N; i++) { X = i; Y = i*4; }
+}
+
+produces two identical IV's (after promotion) on PPC/ARM:
+
+LBB1_1: @bb.preheader
+        mov r3, #0
+        mov r2, r3
+        mov r1, r3
+LBB1_2: @bb
+        ldr r12, LCPI1_0
+        ldr r12, [r12]
+        strh r2, [r12]
+        ldr r12, LCPI1_1
+        ldr r12, [r12]
+        strh r3, [r12]
+        add r1, r1, #1    <- [0,+,1]
+        add r3, r3, #4
+        add r2, r2, #1    <- [0,+,1]
+        cmp r1, r0
+        bne LBB1_2      @bb
+
+
+//===---------------------------------------------------------------------===//
+