dnrops
/
clang
mirror of https://github.com/microsoft/clang.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
61,609 Commits 3 Branches 0 Tags 180 MiB
Commit Graph

10 Commits

Author SHA1 Message Date
Rafael Espindola a3f55b026f Don't pass -O0 to clang_cc1, it is the default. 
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@189910 91177308-0d34-0410-b5e6-96231b3b80d8
 2013-09-04 04:12:25 +00:00
Eric Christopher c07833795a For debug and coverage analysis if we're not optimizing go ahead 
and emit a relatively empty block for a plain break statement. This
enables us to track where we went through a switch.

PR9796 & rdar://11215207

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154420 91177308-0d34-0410-b5e6-96231b3b80d8
 2012-04-10 18:20:19 +00:00
Chris Lattner 421048698b Fix a miscompilation I introduced in r129652, thanks for Eli for tracking 
it down.  we effectively were compile the testcase into:

void test14(int x) {
  switch (x) {
    case 11: break;
    case 42: test14(97);  // fallthrough
    default: test14(42); break;

which is not the same thing at all.  This fixes a miscompilation of 
MallocBench/gs seen on the clang-x86_64-linux-fnt buildbot.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@129679 91177308-0d34-0410-b5e6-96231b3b80d8
 2011-04-17 23:21:26 +00:00
Chris Lattner bbc1c2ef74 when assertions are disabled, labels go away. Hopefully fixes the windows build. 
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@129660 91177308-0d34-0410-b5e6-96231b3b80d8
 2011-04-17 16:19:57 +00:00
Chris Lattner b11f919811 implement rdar://9289524 - case followed immediately by break results in empty IR block, 
a -O0 code quality issue.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@129652 91177308-0d34-0410-b5e6-96231b3b80d8
 2011-04-17 00:54:30 +00:00
Chris Lattner 3f06e27473 Make skipping of vardecls more precise: it's ok to skip a decl if the entire 
compound stmt containing the decl is skipped.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126639 91177308-0d34-0410-b5e6-96231b3b80d8
 2011-02-28 07:22:44 +00:00
Chris Lattner 9467110fce make switch constant folding a bit stronger, handling a missed case. 
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126638 91177308-0d34-0410-b5e6-96231b3b80d8
 2011-02-28 07:16:14 +00:00
Chris Lattner 035287d739 remove a bogus assertion, add a comment. 
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126603 91177308-0d34-0410-b5e6-96231b3b80d8
 2011-02-28 01:06:02 +00:00
Chris Lattner 3858938b04 make switch condition constant folding much more aggressive, handling 
compound statements and break statements.  This implements enough to 
handle PR9322 and rdar://6970405.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126602 91177308-0d34-0410-b5e6-96231b3b80d8
 2011-02-28 01:02:29 +00:00
Chris Lattner fda0f1f5a2 First tiny step to implementing PR9322: build infrastructure for only emitting the 
live case of a switch statement when switching on a constant.  This is terribly
limited, but enough to handle the trivial example included.  Before we would 
emit:

define void @test1(i32 %i) nounwind {
entry:
  %i.addr = alloca i32, align 4
  store i32 %i, i32* %i.addr, align 4
  switch i32 1, label %sw.epilog [
    i32 1, label %sw.bb
  ]

sw.bb:                                            ; preds = %entry
  %tmp = load i32* %i.addr, align 4
  %inc = add nsw i32 %tmp, 1
  store i32 %inc, i32* %i.addr, align 4
  br label %sw.epilog

sw.epilog:                                        ; preds = %sw.bb, %entry
  switch i32 0, label %sw.epilog3 [
    i32 1, label %sw.bb1
  ]

sw.bb1:                                           ; preds = %sw.epilog
  %tmp2 = load i32* %i.addr, align 4
  %add = add nsw i32 %tmp2, 2
  store i32 %add, i32* %i.addr, align 4
  br label %sw.epilog3

sw.epilog3:                                       ; preds = %sw.bb1, %sw.epilog
  ret void
}

now we emit:

define void @test1(i32 %i) nounwind {
entry:
  %i.addr = alloca i32, align 4
  store i32 %i, i32* %i.addr, align 4
  %tmp = load i32* %i.addr, align 4
  %inc = add nsw i32 %tmp, 1
  store i32 %inc, i32* %i.addr, align 4
  ret void
}

This improves -O0 compile time (less IR to generate and shove through the code 
generator) and the clever linux kernel people found a way to fail to build if we 
don't do this optimization.  This step isn't enough to handle the kernel case
though.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126597 91177308-0d34-0410-b5e6-96231b3b80d8
 2011-02-28 00:22:07 +00:00