replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

ArgPromo+DebugInfo: Handle updating debug info over multiple applications of argument promotion. 

While the subprogram map cache used by Dead Argument Elimination works
there, I made a mistake when reusing it for Argument Promotion in
r212128 because ArgPromo may transform functions more than once whereas
DAE transforms each function only once, removing all the dead arguments
in one go.

To address this, ensure that the map is updated after each argument
promotion.

In retrospect it might be a little wasteful to create a map of all
subprograms when only handling a single CGSCC, but the alternative is
walking the debug info for each function in the CGSCC that gets updated.
It's not clear to me what the right tradeoff is there, but since the
current tradeoff seems to be working OK (and the code to keep things
updated is very cheap), let's stick with that for now.

llvm-svn: 213805
This commit is contained in:
David Blaikie 2014-07-23 22:09:29 +00:00
parent 7c60a98f16
commit 8e9cfa5497
2 changed files with 14 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
View File

@ -615,9 +615,13 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F,
// Patch the pointer to LLVM function in debug info descriptor.
auto DI = FunctionDIs.find(F);
if (DI != FunctionDIs.end())
DI->second.replaceFunction(NF);
if (DI != FunctionDIs.end()) {
DISubprogram SP = DI->second;
SP.replaceFunction(NF);
FunctionDIs.erase(DI);
FunctionDIs[NF] = SP;
}
DEBUG(dbgs() << "ARG PROMOTION: Promoting to:" << *NF << "\n"
<< "From: " << *F);

13
llvm/test/Transforms/ArgumentPromotion/dbg.ll
View File

@ -4,14 +4,15 @@
declare void @sink(i32)
define internal void @test(i32* %X) {
%1 = load i32* %X, align 8
call void @sink(i32 %1)
define internal void @test(i32** %X) {
%1 = load i32** %X, align 8
%2 = load i32* %1, align 8
call void @sink(i32 %2)
ret void
}
define void @caller(i32* %Y) {
call void @test(i32* %Y)
define void @caller(i32** %Y) {
call void @test(i32** %Y)
ret void
}
@ -20,6 +21,6 @@ define void @caller(i32* %Y) {
!0 = metadata !{i32 2, metadata !"Debug Info Version", i32 1}
!1 = metadata !{i32 8, i32 0, metadata !2, null}
!2 = metadata !{i32 786478, null, null, metadata !"test", metadata !"test", metadata !"", i32 3, null, i1 true, i1 true, i32 0, i32 0, null, i32 256, i1 false, void (i32*)* @test, null, null, null, i32 3}
!2 = metadata !{i32 786478, null, null, metadata !"test", metadata !"test", metadata !"", i32 3, null, i1 true, i1 true, i32 0, i32 0, null, i32 256, i1 false, void (i32**)* @test, null, null, null, i32 3}
!3 = metadata !{i32 786449, null, i32 4, metadata !"clang version 3.5.0 ", i1 false, metadata !"", i32 0, null, null, metadata !4, null, null, metadata !"", i32 2} ; [ DW_TAG_compile_unit ] [/usr/local/google/home/blaikie/dev/scratch/pr20038/reduce/<stdin>] [DW_LANG_C_plus_plus]
!4 = metadata !{metadata !2}