From 7ecc2fc4ca91b4b0cd30fe74e0250a192d52b17c Mon Sep 17 00:00:00 2001 From: Nick Lewycky Date: Wed, 12 Jan 2011 09:06:19 +0000 Subject: Add another note taken from the gcc bugzilla. llvm-svn: 123315 --- llvm/lib/Target/ARM/README-Thumb.txt | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) (limited to 'llvm/lib/Target') diff --git a/llvm/lib/Target/ARM/README-Thumb.txt b/llvm/lib/Target/ARM/README-Thumb.txt index 6b605bb0a7c..463c440852f 100644 --- a/llvm/lib/Target/ARM/README-Thumb.txt +++ b/llvm/lib/Target/ARM/README-Thumb.txt @@ -68,7 +68,7 @@ LPCRELL0: //===---------------------------------------------------------------------===// -We compiles the following: +We compile the following: define i16 @func_entry_2E_ce(i32 %i) { switch i32 %i, label %bb12.exitStub [ @@ -246,3 +246,22 @@ Thumb2. Rather than having tBR_JTr print a ".align 2" and constant island pass pad it, add a target specific ALIGN instruction instead. That way, GetInstSizeInBytes won't have to over-estimate. It can also be used for loop alignment pass. + +//===---------------------------------------------------------------------===// + +We generate conditional code for icmp when we don't need to. This code: + + int foo(int s) { + return s == 1; + } + +produces: + +foo: + cmp r0, #1 + mov.w r0, #0 + it eq + moveq r0, #1 + bx lr + +when it could use subs + adcs. This is GCC PR46975. -- cgit v1.2.3