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llvm-project/llvm/test/Transforms/Inline/cgscc-invalidate.ll

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[PM] Teach the CGSCC's CG update utility to more carefully invalidate analyses when we're about to break apart an SCC. We can't wait until after breaking apart the SCC to invalidate things: 1) Which SCC do we then invalidate? All of them? 2) Even if we invalidate all of them, a newly created SCC may not have a proxy that will convey the invalidation to functions! Previously we only invalidated one of the SCCs and too late. This led to stale analyses remaining in the cache. And because the caching strategy actually works, they would get used and chaos would ensue. Doing invalidation early is somewhat pessimizing though if we *know* that the SCC structure won't change. So it turns out that the design to make the mutation API force the caller to know the *kind* of mutation in advance was indeed 100% correct and we didn't do enough of it. So this change also splits two cases of switching a call edge to a ref edge into two separate APIs so that callers can clearly test for this and take the easy path without invalidating when appropriate. This is particularly important in this case as we expect most inlines to be between functions in separate SCCs and so the common case is that we don't have to so aggressively invalidate analyses. The LCG API change in turn needed some basic cleanups and better testing in its unittest. No interesting functionality changed there other than more coverage of the returned sequence of SCCs. While this seems like an obvious improvement over the current state, I'd like to revisit the core concept of invalidating within the CG-update layer at all. I'm wondering if we would be better served forcing the callers to handle the invalidation beforehand in the cases that they can handle it. An interesting example is when we want to teach the inliner to *update and preserve* analyses. But we can cross that bridge when we get there. With this patch, the new pass manager an build all of the LLVM test suite at -O3 and everything passes. =D I haven't bootstrapped yet and I'm sure there are still plenty of bugs, but this gives a nice baseline so I'm going to increasingly focus on fleshing out the missing functionality, especially the bits that are just turned off right now in order to let us establish this baseline. llvm-svn: 290664
2016-12-28 18:34:50 +08:00
; This test tries to ensure that the inliner successfully invalidates function
; analyses after inlining into the function body.
;
; The strategy for these tests is to compute domtree over all the functions,
; then run the inliner, and then verify the domtree. Then we can arrange the
; inline to disturb the domtree (easy) and detect any stale cached entries in
; the verifier. We do the initial computation both *inside* the CGSCC walk and
; in a pre-step to make sure both work.
;
; RUN: opt < %s -passes='function(require<domtree>),cgscc(inline,function(verify<domtree>))' -S | FileCheck %s
; RUN: opt < %s -passes='cgscc(function(require<domtree>),inline,function(verify<domtree>))' -S | FileCheck %s
; An external function used to control branches.
declare i1 @flag()
; CHECK-LABEL: declare i1 @flag()
; The utility function with interesting control flow that gets inlined below to
; perturb the dominator tree.
define internal void @callee() {
; CHECK-LABEL: @callee
entry:
%ptr = alloca i8
%flag = call i1 @flag()
br i1 %flag, label %then, label %else
then:
store volatile i8 42, i8* %ptr
br label %return
else:
store volatile i8 -42, i8* %ptr
br label %return
return:
ret void
}
; The 'test1_' prefixed functions test the basic scenario of inlining
; destroying dominator tree.
define void @test1_caller() {
; CHECK-LABEL: define void @test1_caller()
entry:
call void @callee()
; CHECK-NOT: @callee
ret void
; CHECK: ret void
}
; The 'test2_' prefixed functions test the scenario of not inlining preserving
; dominators.
define void @test2_caller() {
; CHECK-LABEL: define void @test2_caller()
entry:
call void @callee() noinline
; CHECK: call void @callee
ret void
; CHECK: ret void
}
; The 'test3_' prefixed functions test the scenario of not inlining preserving
; dominators after splitting an SCC into two smaller SCCs.
[PM/Inliner] Make the new PM's inliner process call edges across an entire SCC before iterating on newly-introduced call edges resulting from any inlined function bodies. This more closely matches the behavior of the old PM's inliner. While it wasn't really clear to me initially, this behavior is actually essential to the inliner behaving reasonably in its current design. Because the inliner is fundamentally a bottom-up inliner and all of its cost modeling is designed around that it often runs into trouble within an SCC where we don't have any meaningful bottom-up ordering to use. In addition to potentially cyclic, infinite inlining that we block with the inline history mechanism, it can also take seemingly simple call graph patterns within an SCC and turn them into *insanely* large functions by accidentally working top-down across the SCC without any of the threshold limitations that traditional top-down inliners use. Consider this diabolical monster.cpp file that Richard Smith came up with to help demonstrate this issue: ``` template <int N> extern const char *str; void g(const char *); template <bool K, int N> void f(bool *B, bool *E) { if (K) g(str<N>); if (B == E) return; if (*B) f<true, N + 1>(B + 1, E); else f<false, N + 1>(B + 1, E); } template <> void f<false, MAX>(bool *B, bool *E) { return f<false, 0>(B, E); } template <> void f<true, MAX>(bool *B, bool *E) { return f<true, 0>(B, E); } extern bool *arr, *end; void test() { f<false, 0>(arr, end); } ``` When compiled with '-DMAX=N' for various values of N, this will create an SCC with a reasonably large number of functions. Previously, the inliner would try to exhaust the inlining candidates in a single function before moving on. This, unfortunately, turns it into a top-down inliner within the SCC. Because our thresholds were never built for that, we will incrementally decide that it is always worth inlining and proceed to flatten the entire SCC into that one function. What's worse, we'll then proceed to the next function, and do the exact same thing except we'll skip the first function, and so on. And at each step, we'll also make some of the constant factors larger, which is awesome. The fix in this patch is the obvious one which makes the new PM's inliner use the same technique used by the old PM: consider all the call edges across the entire SCC before beginning to process call edges introduced by inlining. The result of this is essentially to distribute the inlining across the SCC so that every function incrementally grows toward the inline thresholds rather than allowing the inliner to grow one of the functions vastly beyond the threshold. The code for this is a bit awkward, but it works out OK. We could consider in the future doing something more powerful here such as prioritized order (via lowest cost and/or profile info) and/or a code-growth budget per SCC. However, both of those would require really substantial work both to design the system in a way that wouldn't break really useful abstraction decomposition properties of the current inliner and to be tuned across a reasonably diverse set of code and workloads. It also seems really risky in many ways. I have only found a single real-world file that triggers the bad behavior here and it is generated code that has a pretty pathological pattern. I'm not worried about the inliner not doing an *awesome* job here as long as it does *ok*. On the other hand, the cases that will be tricky to get right in a prioritized scheme with a budget will be more common and idiomatic for at least some frontends (C++ and Rust at least). So while these approaches are still really interesting, I'm not in a huge rush to go after them. Staying even closer to the existing PM's behavior, especially when this easy to do, seems like the right short to medium term approach. I don't really have a test case that makes sense yet... I'll try to find a variant of the IR produced by the monster template metaprogram that is both small enough to be sane and large enough to clearly show when we get this wrong in the future. But I'm not confident this exists. And the behavior change here *should* be unobservable without snooping on debug logging. So there isn't really much to test. The test case updates come from two incidental changes: 1) We now visit functions in an SCC in the opposite order. I don't think there really is a "right" order here, so I just update the test cases. 2) We no longer compute some analyses when an SCC has no call instructions that we consider for inlining. llvm-svn: 297374
2017-03-09 19:35:40 +08:00
; This function ends up split into a separate SCC, which can cause its analyses
; to become stale if the splitting doesn't properly invalidate things. Also, as
; a consequence of being split out, test3_f is too large to inline by the time
; we get here.
define void @test3_g() {
; CHECK-LABEL: define void @test3_g()
[PM] Teach the CGSCC's CG update utility to more carefully invalidate analyses when we're about to break apart an SCC. We can't wait until after breaking apart the SCC to invalidate things: 1) Which SCC do we then invalidate? All of them? 2) Even if we invalidate all of them, a newly created SCC may not have a proxy that will convey the invalidation to functions! Previously we only invalidated one of the SCCs and too late. This led to stale analyses remaining in the cache. And because the caching strategy actually works, they would get used and chaos would ensue. Doing invalidation early is somewhat pessimizing though if we *know* that the SCC structure won't change. So it turns out that the design to make the mutation API force the caller to know the *kind* of mutation in advance was indeed 100% correct and we didn't do enough of it. So this change also splits two cases of switching a call edge to a ref edge into two separate APIs so that callers can clearly test for this and take the easy path without invalidating when appropriate. This is particularly important in this case as we expect most inlines to be between functions in separate SCCs and so the common case is that we don't have to so aggressively invalidate analyses. The LCG API change in turn needed some basic cleanups and better testing in its unittest. No interesting functionality changed there other than more coverage of the returned sequence of SCCs. While this seems like an obvious improvement over the current state, I'd like to revisit the core concept of invalidating within the CG-update layer at all. I'm wondering if we would be better served forcing the callers to handle the invalidation beforehand in the cases that they can handle it. An interesting example is when we want to teach the inliner to *update and preserve* analyses. But we can cross that bridge when we get there. With this patch, the new pass manager an build all of the LLVM test suite at -O3 and everything passes. =D I haven't bootstrapped yet and I'm sure there are still plenty of bugs, but this gives a nice baseline so I'm going to increasingly focus on fleshing out the missing functionality, especially the bits that are just turned off right now in order to let us establish this baseline. llvm-svn: 290664
2016-12-28 18:34:50 +08:00
entry:
[PM/Inliner] Make the new PM's inliner process call edges across an entire SCC before iterating on newly-introduced call edges resulting from any inlined function bodies. This more closely matches the behavior of the old PM's inliner. While it wasn't really clear to me initially, this behavior is actually essential to the inliner behaving reasonably in its current design. Because the inliner is fundamentally a bottom-up inliner and all of its cost modeling is designed around that it often runs into trouble within an SCC where we don't have any meaningful bottom-up ordering to use. In addition to potentially cyclic, infinite inlining that we block with the inline history mechanism, it can also take seemingly simple call graph patterns within an SCC and turn them into *insanely* large functions by accidentally working top-down across the SCC without any of the threshold limitations that traditional top-down inliners use. Consider this diabolical monster.cpp file that Richard Smith came up with to help demonstrate this issue: ``` template <int N> extern const char *str; void g(const char *); template <bool K, int N> void f(bool *B, bool *E) { if (K) g(str<N>); if (B == E) return; if (*B) f<true, N + 1>(B + 1, E); else f<false, N + 1>(B + 1, E); } template <> void f<false, MAX>(bool *B, bool *E) { return f<false, 0>(B, E); } template <> void f<true, MAX>(bool *B, bool *E) { return f<true, 0>(B, E); } extern bool *arr, *end; void test() { f<false, 0>(arr, end); } ``` When compiled with '-DMAX=N' for various values of N, this will create an SCC with a reasonably large number of functions. Previously, the inliner would try to exhaust the inlining candidates in a single function before moving on. This, unfortunately, turns it into a top-down inliner within the SCC. Because our thresholds were never built for that, we will incrementally decide that it is always worth inlining and proceed to flatten the entire SCC into that one function. What's worse, we'll then proceed to the next function, and do the exact same thing except we'll skip the first function, and so on. And at each step, we'll also make some of the constant factors larger, which is awesome. The fix in this patch is the obvious one which makes the new PM's inliner use the same technique used by the old PM: consider all the call edges across the entire SCC before beginning to process call edges introduced by inlining. The result of this is essentially to distribute the inlining across the SCC so that every function incrementally grows toward the inline thresholds rather than allowing the inliner to grow one of the functions vastly beyond the threshold. The code for this is a bit awkward, but it works out OK. We could consider in the future doing something more powerful here such as prioritized order (via lowest cost and/or profile info) and/or a code-growth budget per SCC. However, both of those would require really substantial work both to design the system in a way that wouldn't break really useful abstraction decomposition properties of the current inliner and to be tuned across a reasonably diverse set of code and workloads. It also seems really risky in many ways. I have only found a single real-world file that triggers the bad behavior here and it is generated code that has a pretty pathological pattern. I'm not worried about the inliner not doing an *awesome* job here as long as it does *ok*. On the other hand, the cases that will be tricky to get right in a prioritized scheme with a budget will be more common and idiomatic for at least some frontends (C++ and Rust at least). So while these approaches are still really interesting, I'm not in a huge rush to go after them. Staying even closer to the existing PM's behavior, especially when this easy to do, seems like the right short to medium term approach. I don't really have a test case that makes sense yet... I'll try to find a variant of the IR produced by the monster template metaprogram that is both small enough to be sane and large enough to clearly show when we get this wrong in the future. But I'm not confident this exists. And the behavior change here *should* be unobservable without snooping on debug logging. So there isn't really much to test. The test case updates come from two incidental changes: 1) We now visit functions in an SCC in the opposite order. I don't think there really is a "right" order here, so I just update the test cases. 2) We no longer compute some analyses when an SCC has no call instructions that we consider for inlining. llvm-svn: 297374
2017-03-09 19:35:40 +08:00
; Create the second edge in the SCC cycle.
call void @test3_f()
[PM] Teach the CGSCC's CG update utility to more carefully invalidate analyses when we're about to break apart an SCC. We can't wait until after breaking apart the SCC to invalidate things: 1) Which SCC do we then invalidate? All of them? 2) Even if we invalidate all of them, a newly created SCC may not have a proxy that will convey the invalidation to functions! Previously we only invalidated one of the SCCs and too late. This led to stale analyses remaining in the cache. And because the caching strategy actually works, they would get used and chaos would ensue. Doing invalidation early is somewhat pessimizing though if we *know* that the SCC structure won't change. So it turns out that the design to make the mutation API force the caller to know the *kind* of mutation in advance was indeed 100% correct and we didn't do enough of it. So this change also splits two cases of switching a call edge to a ref edge into two separate APIs so that callers can clearly test for this and take the easy path without invalidating when appropriate. This is particularly important in this case as we expect most inlines to be between functions in separate SCCs and so the common case is that we don't have to so aggressively invalidate analyses. The LCG API change in turn needed some basic cleanups and better testing in its unittest. No interesting functionality changed there other than more coverage of the returned sequence of SCCs. While this seems like an obvious improvement over the current state, I'd like to revisit the core concept of invalidating within the CG-update layer at all. I'm wondering if we would be better served forcing the callers to handle the invalidation beforehand in the cases that they can handle it. An interesting example is when we want to teach the inliner to *update and preserve* analyses. But we can cross that bridge when we get there. With this patch, the new pass manager an build all of the LLVM test suite at -O3 and everything passes. =D I haven't bootstrapped yet and I'm sure there are still plenty of bugs, but this gives a nice baseline so I'm going to increasingly focus on fleshing out the missing functionality, especially the bits that are just turned off right now in order to let us establish this baseline. llvm-svn: 290664
2016-12-28 18:34:50 +08:00
; CHECK: call void @test3_f()
; Pull interesting CFG into this function.
call void @callee()
; CHECK-NOT: call void @callee()
ret void
; CHECK: ret void
}
[PM/Inliner] Make the new PM's inliner process call edges across an entire SCC before iterating on newly-introduced call edges resulting from any inlined function bodies. This more closely matches the behavior of the old PM's inliner. While it wasn't really clear to me initially, this behavior is actually essential to the inliner behaving reasonably in its current design. Because the inliner is fundamentally a bottom-up inliner and all of its cost modeling is designed around that it often runs into trouble within an SCC where we don't have any meaningful bottom-up ordering to use. In addition to potentially cyclic, infinite inlining that we block with the inline history mechanism, it can also take seemingly simple call graph patterns within an SCC and turn them into *insanely* large functions by accidentally working top-down across the SCC without any of the threshold limitations that traditional top-down inliners use. Consider this diabolical monster.cpp file that Richard Smith came up with to help demonstrate this issue: ``` template <int N> extern const char *str; void g(const char *); template <bool K, int N> void f(bool *B, bool *E) { if (K) g(str<N>); if (B == E) return; if (*B) f<true, N + 1>(B + 1, E); else f<false, N + 1>(B + 1, E); } template <> void f<false, MAX>(bool *B, bool *E) { return f<false, 0>(B, E); } template <> void f<true, MAX>(bool *B, bool *E) { return f<true, 0>(B, E); } extern bool *arr, *end; void test() { f<false, 0>(arr, end); } ``` When compiled with '-DMAX=N' for various values of N, this will create an SCC with a reasonably large number of functions. Previously, the inliner would try to exhaust the inlining candidates in a single function before moving on. This, unfortunately, turns it into a top-down inliner within the SCC. Because our thresholds were never built for that, we will incrementally decide that it is always worth inlining and proceed to flatten the entire SCC into that one function. What's worse, we'll then proceed to the next function, and do the exact same thing except we'll skip the first function, and so on. And at each step, we'll also make some of the constant factors larger, which is awesome. The fix in this patch is the obvious one which makes the new PM's inliner use the same technique used by the old PM: consider all the call edges across the entire SCC before beginning to process call edges introduced by inlining. The result of this is essentially to distribute the inlining across the SCC so that every function incrementally grows toward the inline thresholds rather than allowing the inliner to grow one of the functions vastly beyond the threshold. The code for this is a bit awkward, but it works out OK. We could consider in the future doing something more powerful here such as prioritized order (via lowest cost and/or profile info) and/or a code-growth budget per SCC. However, both of those would require really substantial work both to design the system in a way that wouldn't break really useful abstraction decomposition properties of the current inliner and to be tuned across a reasonably diverse set of code and workloads. It also seems really risky in many ways. I have only found a single real-world file that triggers the bad behavior here and it is generated code that has a pretty pathological pattern. I'm not worried about the inliner not doing an *awesome* job here as long as it does *ok*. On the other hand, the cases that will be tricky to get right in a prioritized scheme with a budget will be more common and idiomatic for at least some frontends (C++ and Rust at least). So while these approaches are still really interesting, I'm not in a huge rush to go after them. Staying even closer to the existing PM's behavior, especially when this easy to do, seems like the right short to medium term approach. I don't really have a test case that makes sense yet... I'll try to find a variant of the IR produced by the monster template metaprogram that is both small enough to be sane and large enough to clearly show when we get this wrong in the future. But I'm not confident this exists. And the behavior change here *should* be unobservable without snooping on debug logging. So there isn't really much to test. The test case updates come from two incidental changes: 1) We now visit functions in an SCC in the opposite order. I don't think there really is a "right" order here, so I just update the test cases. 2) We no longer compute some analyses when an SCC has no call instructions that we consider for inlining. llvm-svn: 297374
2017-03-09 19:35:40 +08:00
; The second function gets visited first and we end up inlining everything we
; can into this routine. That splits test3_g into a separate SCC that is enqued
; for later processing.
define void @test3_f() {
; CHECK-LABEL: define void @test3_f()
[PM] Teach the CGSCC's CG update utility to more carefully invalidate analyses when we're about to break apart an SCC. We can't wait until after breaking apart the SCC to invalidate things: 1) Which SCC do we then invalidate? All of them? 2) Even if we invalidate all of them, a newly created SCC may not have a proxy that will convey the invalidation to functions! Previously we only invalidated one of the SCCs and too late. This led to stale analyses remaining in the cache. And because the caching strategy actually works, they would get used and chaos would ensue. Doing invalidation early is somewhat pessimizing though if we *know* that the SCC structure won't change. So it turns out that the design to make the mutation API force the caller to know the *kind* of mutation in advance was indeed 100% correct and we didn't do enough of it. So this change also splits two cases of switching a call edge to a ref edge into two separate APIs so that callers can clearly test for this and take the easy path without invalidating when appropriate. This is particularly important in this case as we expect most inlines to be between functions in separate SCCs and so the common case is that we don't have to so aggressively invalidate analyses. The LCG API change in turn needed some basic cleanups and better testing in its unittest. No interesting functionality changed there other than more coverage of the returned sequence of SCCs. While this seems like an obvious improvement over the current state, I'd like to revisit the core concept of invalidating within the CG-update layer at all. I'm wondering if we would be better served forcing the callers to handle the invalidation beforehand in the cases that they can handle it. An interesting example is when we want to teach the inliner to *update and preserve* analyses. But we can cross that bridge when we get there. With this patch, the new pass manager an build all of the LLVM test suite at -O3 and everything passes. =D I haven't bootstrapped yet and I'm sure there are still plenty of bugs, but this gives a nice baseline so I'm going to increasingly focus on fleshing out the missing functionality, especially the bits that are just turned off right now in order to let us establish this baseline. llvm-svn: 290664
2016-12-28 18:34:50 +08:00
entry:
[PM/Inliner] Make the new PM's inliner process call edges across an entire SCC before iterating on newly-introduced call edges resulting from any inlined function bodies. This more closely matches the behavior of the old PM's inliner. While it wasn't really clear to me initially, this behavior is actually essential to the inliner behaving reasonably in its current design. Because the inliner is fundamentally a bottom-up inliner and all of its cost modeling is designed around that it often runs into trouble within an SCC where we don't have any meaningful bottom-up ordering to use. In addition to potentially cyclic, infinite inlining that we block with the inline history mechanism, it can also take seemingly simple call graph patterns within an SCC and turn them into *insanely* large functions by accidentally working top-down across the SCC without any of the threshold limitations that traditional top-down inliners use. Consider this diabolical monster.cpp file that Richard Smith came up with to help demonstrate this issue: ``` template <int N> extern const char *str; void g(const char *); template <bool K, int N> void f(bool *B, bool *E) { if (K) g(str<N>); if (B == E) return; if (*B) f<true, N + 1>(B + 1, E); else f<false, N + 1>(B + 1, E); } template <> void f<false, MAX>(bool *B, bool *E) { return f<false, 0>(B, E); } template <> void f<true, MAX>(bool *B, bool *E) { return f<true, 0>(B, E); } extern bool *arr, *end; void test() { f<false, 0>(arr, end); } ``` When compiled with '-DMAX=N' for various values of N, this will create an SCC with a reasonably large number of functions. Previously, the inliner would try to exhaust the inlining candidates in a single function before moving on. This, unfortunately, turns it into a top-down inliner within the SCC. Because our thresholds were never built for that, we will incrementally decide that it is always worth inlining and proceed to flatten the entire SCC into that one function. What's worse, we'll then proceed to the next function, and do the exact same thing except we'll skip the first function, and so on. And at each step, we'll also make some of the constant factors larger, which is awesome. The fix in this patch is the obvious one which makes the new PM's inliner use the same technique used by the old PM: consider all the call edges across the entire SCC before beginning to process call edges introduced by inlining. The result of this is essentially to distribute the inlining across the SCC so that every function incrementally grows toward the inline thresholds rather than allowing the inliner to grow one of the functions vastly beyond the threshold. The code for this is a bit awkward, but it works out OK. We could consider in the future doing something more powerful here such as prioritized order (via lowest cost and/or profile info) and/or a code-growth budget per SCC. However, both of those would require really substantial work both to design the system in a way that wouldn't break really useful abstraction decomposition properties of the current inliner and to be tuned across a reasonably diverse set of code and workloads. It also seems really risky in many ways. I have only found a single real-world file that triggers the bad behavior here and it is generated code that has a pretty pathological pattern. I'm not worried about the inliner not doing an *awesome* job here as long as it does *ok*. On the other hand, the cases that will be tricky to get right in a prioritized scheme with a budget will be more common and idiomatic for at least some frontends (C++ and Rust at least). So while these approaches are still really interesting, I'm not in a huge rush to go after them. Staying even closer to the existing PM's behavior, especially when this easy to do, seems like the right short to medium term approach. I don't really have a test case that makes sense yet... I'll try to find a variant of the IR produced by the monster template metaprogram that is both small enough to be sane and large enough to clearly show when we get this wrong in the future. But I'm not confident this exists. And the behavior change here *should* be unobservable without snooping on debug logging. So there isn't really much to test. The test case updates come from two incidental changes: 1) We now visit functions in an SCC in the opposite order. I don't think there really is a "right" order here, so I just update the test cases. 2) We no longer compute some analyses when an SCC has no call instructions that we consider for inlining. llvm-svn: 297374
2017-03-09 19:35:40 +08:00
; Create the first edge in the SCC cycle.
call void @test3_g()
; CHECK-NOT: @test3_g()
[PM] Teach the CGSCC's CG update utility to more carefully invalidate analyses when we're about to break apart an SCC. We can't wait until after breaking apart the SCC to invalidate things: 1) Which SCC do we then invalidate? All of them? 2) Even if we invalidate all of them, a newly created SCC may not have a proxy that will convey the invalidation to functions! Previously we only invalidated one of the SCCs and too late. This led to stale analyses remaining in the cache. And because the caching strategy actually works, they would get used and chaos would ensue. Doing invalidation early is somewhat pessimizing though if we *know* that the SCC structure won't change. So it turns out that the design to make the mutation API force the caller to know the *kind* of mutation in advance was indeed 100% correct and we didn't do enough of it. So this change also splits two cases of switching a call edge to a ref edge into two separate APIs so that callers can clearly test for this and take the easy path without invalidating when appropriate. This is particularly important in this case as we expect most inlines to be between functions in separate SCCs and so the common case is that we don't have to so aggressively invalidate analyses. The LCG API change in turn needed some basic cleanups and better testing in its unittest. No interesting functionality changed there other than more coverage of the returned sequence of SCCs. While this seems like an obvious improvement over the current state, I'd like to revisit the core concept of invalidating within the CG-update layer at all. I'm wondering if we would be better served forcing the callers to handle the invalidation beforehand in the cases that they can handle it. An interesting example is when we want to teach the inliner to *update and preserve* analyses. But we can cross that bridge when we get there. With this patch, the new pass manager an build all of the LLVM test suite at -O3 and everything passes. =D I haven't bootstrapped yet and I'm sure there are still plenty of bugs, but this gives a nice baseline so I'm going to increasingly focus on fleshing out the missing functionality, especially the bits that are just turned off right now in order to let us establish this baseline. llvm-svn: 290664
2016-12-28 18:34:50 +08:00
; CHECK: call void @test3_f()
; Pull interesting CFG into this function.
call void @callee()
; CHECK-NOT: call void @callee()
ret void
; CHECK: ret void
}