Evan Cheng c1db873871 Let targets provide hooks that compute known zero and ones for any_extend ... and extload's. If they are implemented as zero-extend, or implicitly zero-extend, then this can enable more demanded bits optimizations. e.g. define void @foo(i16* %ptr, i32 %a) nounwind { entry: %tmp1 = icmp ult i32 %a, 100 br i1 %tmp1, label %bb1, label %bb2 bb1: %tmp2 = load i16* %ptr, align 2 br label %bb2 bb2: %tmp3 = phi i16 [ 0, %entry ], [ %tmp2, %bb1 ] %cmp = icmp ult i16 %tmp3, 24 br i1 %cmp, label %bb3, label %exit bb3: call void @bar() nounwind br label %exit exit: ret void } This compiles to the followings before: push {lr} mov r2, #0 cmp r1, #99 bhi LBB0_2 @ BB#1: @ %bb1 ldrh r2, [r0] LBB0_2: @ %bb2 uxth r0, r2 cmp r0, #23 bhi LBB0_4 @ BB#3: @ %bb3 bl _bar LBB0_4: @ %exit pop {lr} bx lr The uxth is not needed since ldrh implicitly zero-extend the high bits. With this change it's eliminated. rdar://12771555 llvm-svn: 169459		2012-12-06 01:28:01 +00:00
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Analysis	Have CannotBeNegativeZero() be aware of the nsz fast-math flag	2012-12-06 00:07:09 +00:00
Archive	Sort includes for all of the .h files under the 'lib' tree. These were	2012-12-04 07:12:27 +00:00
AsmParser	Split up the ParseOptionalAttrs method into three different methods for each	2012-12-04 23:40:58 +00:00
Bitcode	Sort includes for all of the .h files under the 'lib' tree. These were	2012-12-04 07:12:27 +00:00
CodeGen	Let targets provide hooks that compute known zero and ones for any_extend	2012-12-06 01:28:01 +00:00
DebugInfo	Sort includes for all of the .h files under the 'lib' tree. These were	2012-12-04 07:12:27 +00:00
ExecutionEngine	Adjust JIT target triple on OS X to match the current architecture.	2012-12-05 19:09:13 +00:00
Linker	Use the new script to sort the includes of every file under lib.	2012-12-03 16:50:05 +00:00
MC	change MCContext to work on the doInitialization/doFinalization model	2012-12-06 00:50:55 +00:00
Object	Use the new script to sort the includes of every file under lib.	2012-12-03 16:50:05 +00:00
Option	Copy clang/Driver/<Option parsing stuff> to llvm.	2012-12-05 00:29:32 +00:00
Support	Make NaCl naming consistent. The triple OSType is called NaCl and is represented	2012-12-04 18:37:26 +00:00
TableGen	Sort includes for all of the .h files under the 'lib' tree. These were	2012-12-04 07:12:27 +00:00
Target	Let targets provide hooks that compute known zero and ones for any_extend	2012-12-06 01:28:01 +00:00
Transforms	Set the 'MadeChange' variable if we are deleting blocks.	2012-12-06 00:30:20 +00:00
VMCore	Fix name. The array is unboundED.	2012-12-05 21:43:30 +00:00
CMakeLists.txt	Copy clang/Driver/<Option parsing stuff> to llvm.	2012-12-05 00:29:32 +00:00
LLVMBuild.txt	Copy clang/Driver/<Option parsing stuff> to llvm.	2012-12-05 00:29:32 +00:00
Makefile	Copy clang/Driver/<Option parsing stuff> to llvm.	2012-12-05 00:29:32 +00:00