From f9e9e599c0138b2403bc89934ddace0c2a8d84d6 Mon Sep 17 00:00:00 2001 From: Wentao Zhang <35722712+whentojump@users.noreply.github.com> Date: Thu, 23 May 2024 22:06:43 -0500 Subject: [PATCH] [Coverage][Expansion] handle nested macros in scratch space (#89869) The problematic program is as follows: ```shell #define pre_a 0 #define PRE(x) pre_##x void f(void) { PRE(a) && 0; } int main(void) { return 0; } ``` in which after token concatenation (`##`), there's another nested macro `pre_a`. Currently only the outer expansion region will be produced. ([compiler explorer link](https://godbolt.org/#g:!((g:!((g:!((h:codeEditor,i:(filename:'1',fontScale:14,fontUsePx:'0',j:1,lang:___c,selection:(endColumn:29,endLineNumber:8,positionColumn:29,positionLineNumber:8,selectionStartColumn:29,selectionStartLineNumber:8,startColumn:29,startLineNumber:8),source:'%23define+pre_a+0%0A%23define+PRE(x)+pre_%23%23x%0A%0Avoid+f(void)+%7B%0A++++PRE(a)+%26%26+0%3B%0A%7D%0A%0Aint+main(void)+%7B+return+0%3B+%7D'),l:'5',n:'0',o:'C+source+%231',t:'0')),k:51.69491525423727,l:'4',n:'0',o:'',s:0,t:'0'),(g:!((g:!((h:compiler,i:(compiler:cclang_assertions_trunk,filters:(b:'0',binary:'1',binaryObject:'1',commentOnly:'0',debugCalls:'1',demangle:'0',directives:'0',execute:'0',intel:'0',libraryCode:'1',trim:'1',verboseDemangling:'0'),flagsViewOpen:'1',fontScale:14,fontUsePx:'0',j:2,lang:___c,libs:!(),options:'-fprofile-instr-generate+-fcoverage-mapping+-fcoverage-mcdc+-Xclang+-dump-coverage-mapping+',overrides:!(),selection:(endColumn:1,endLineNumber:1,positionColumn:1,positionLineNumber:1,selectionStartColumn:1,selectionStartLineNumber:1,startColumn:1,startLineNumber:1),source:1),l:'5',n:'0',o:'+x86-64+clang+(assertions+trunk)+(Editor+%231)',t:'0')),k:34.5741843594503,l:'4',m:28.903654485049834,n:'0',o:'',s:0,t:'0'),(g:!((h:output,i:(compilerName:'x86-64+clang+(trunk)',editorid:1,fontScale:14,fontUsePx:'0',j:2,wrap:'1'),l:'5',n:'0',o:'Output+of+x86-64+clang+(assertions+trunk)+(Compiler+%232)',t:'0')),header:(),l:'4',m:71.09634551495017,n:'0',o:'',s:0,t:'0')),k:48.30508474576271,l:'3',n:'0',o:'',t:'0')),l:'2',m:100,n:'0',o:'',t:'0')),version:4)) ```text f: File 0, 4:14 -> 6:2 = #0 Decision,File 0, 5:5 -> 5:16 = M:0, C:2 Expansion,File 0, 5:5 -> 5:8 = #0 (Expanded file = 1) File 0, 5:15 -> 5:16 = #1 Branch,File 0, 5:15 -> 5:16 = 0, 0 [2,0,0] File 1, 2:16 -> 2:23 = #0 File 2, 1:15 -> 1:16 = #0 File 2, 1:15 -> 1:16 = #0 Branch,File 2, 1:15 -> 1:16 = 0, 0 [1,2,0] ``` The inner expansion region isn't produced because: 1. In the range-based for loop quoted below, each sloc is processed and possibly emit a corresponding expansion region. 2. For our sloc in question, its direct parent returned by `getIncludeOrExpansionLoc()` is a ``, because that's how `##` is processed. https://github.com/llvm/llvm-project/blob/88b6186af3908c55b357858eb348b5143f21c289/clang/lib/CodeGen/CoverageMappingGen.cpp#L518-L520 3. This `` cannot be found in the FileID mapping so `ParentFileID` will be assigned an `std::nullopt` https://github.com/llvm/llvm-project/blob/88b6186af3908c55b357858eb348b5143f21c289/clang/lib/CodeGen/CoverageMappingGen.cpp#L521-L526 4. As a result this iteration of for loop finishes early and no expansion region is added for the sloc. This problem gets worse with MC/DC: as the example shows, there's a branch from File 2 but File 2 itself is missing. This will trigger assertion failures. The fix is more or less a workaround and takes a similar approach as #89573. ~~Depends on #89573.~~ This includes #89573. Kudos to @chapuni! This and #89573 together fix #87000: I tested locally, both the reduced program and my original use case (fwiw, Linux kernel) can run successfully. --------- Co-authored-by: NAKAMURA Takumi --- clang/lib/CodeGen/CoverageMappingGen.cpp | 45 ++++++++++++++-- clang/test/CoverageMapping/builtinmacro.c | 2 +- clang/test/CoverageMapping/macros.c | 8 +-- .../test/CoverageMapping/mcdc-scratch-space.c | 52 ++++++++++++++++--- 4 files changed, 91 insertions(+), 16 deletions(-) diff --git a/clang/lib/CodeGen/CoverageMappingGen.cpp b/clang/lib/CodeGen/CoverageMappingGen.cpp index 993d7cc7e21fab..05de50e3f1216d 100644 --- a/clang/lib/CodeGen/CoverageMappingGen.cpp +++ b/clang/lib/CodeGen/CoverageMappingGen.cpp @@ -294,10 +294,36 @@ class CoverageMappingBuilder { return SM.getLocForEndOfFile(SM.getFileID(Loc)); } - /// Find out where the current file is included or macro is expanded. - SourceLocation getIncludeOrExpansionLoc(SourceLocation Loc) { - return Loc.isMacroID() ? SM.getImmediateExpansionRange(Loc).getBegin() - : SM.getIncludeLoc(SM.getFileID(Loc)); + /// Find out where a macro is expanded. If the immediate result is a + /// , keep looking until the result isn't. Return a pair of + /// \c SourceLocation. The first object is always the begin sloc of found + /// result. The second should be checked by the caller: if it has value, it's + /// the end sloc of the found result. Otherwise the while loop didn't get + /// executed, which means the location wasn't changed and the caller has to + /// learn the end sloc from somewhere else. + std::pair> + getNonScratchExpansionLoc(SourceLocation Loc) { + std::optional EndLoc = std::nullopt; + while (Loc.isMacroID() && + SM.isWrittenInScratchSpace(SM.getSpellingLoc(Loc))) { + auto ExpansionRange = SM.getImmediateExpansionRange(Loc); + Loc = ExpansionRange.getBegin(); + EndLoc = ExpansionRange.getEnd(); + } + return std::make_pair(Loc, EndLoc); + } + + /// Find out where the current file is included or macro is expanded. If + /// \c AcceptScratch is set to false, keep looking for expansions until the + /// found sloc is not a . + SourceLocation getIncludeOrExpansionLoc(SourceLocation Loc, + bool AcceptScratch = true) { + if (!Loc.isMacroID()) + return SM.getIncludeLoc(SM.getFileID(Loc)); + Loc = SM.getImmediateExpansionRange(Loc).getBegin(); + if (AcceptScratch) + return Loc; + return getNonScratchExpansionLoc(Loc).first; } /// Return true if \c Loc is a location in a built-in macro. @@ -344,6 +370,15 @@ class CoverageMappingBuilder { for (auto &Region : SourceRegions) { SourceLocation Loc = Region.getBeginLoc(); + // Replace Region with its definition if it is in . + auto NonScratchExpansionLoc = getNonScratchExpansionLoc(Loc); + auto EndLoc = NonScratchExpansionLoc.second; + if (EndLoc.has_value()) { + Loc = NonScratchExpansionLoc.first; + Region.setStartLoc(Loc); + Region.setEndLoc(EndLoc.value()); + } + // Replace Loc with FileLoc if it is expanded with system headers. if (!SystemHeadersCoverage && SM.isInSystemMacro(Loc)) { auto BeginLoc = SM.getSpellingLoc(Loc); @@ -538,7 +573,7 @@ class CoverageMappingBuilder { SourceRegionFilter Filter; for (const auto &FM : FileIDMapping) { SourceLocation ExpandedLoc = FM.second.second; - SourceLocation ParentLoc = getIncludeOrExpansionLoc(ExpandedLoc); + SourceLocation ParentLoc = getIncludeOrExpansionLoc(ExpandedLoc, false); if (ParentLoc.isInvalid()) continue; diff --git a/clang/test/CoverageMapping/builtinmacro.c b/clang/test/CoverageMapping/builtinmacro.c index abcdc191523a5d..5d5a176aa7d87e 100644 --- a/clang/test/CoverageMapping/builtinmacro.c +++ b/clang/test/CoverageMapping/builtinmacro.c @@ -4,7 +4,7 @@ // CHECK: filename const char *filename (const char *name) { // CHECK-NEXT: File 0, [[@LINE]]:41 -> [[@LINE+3]]:2 = #0 - static const char this_file[] = __FILE__; + static const char this_file[] = __FILE__; // CHECK-NEXT: File 0, [[@LINE]]:35 -> [[@LINE]]:35 = #0 return this_file; } diff --git a/clang/test/CoverageMapping/macros.c b/clang/test/CoverageMapping/macros.c index 6bd3be434139a2..fcf21170ef135c 100644 --- a/clang/test/CoverageMapping/macros.c +++ b/clang/test/CoverageMapping/macros.c @@ -80,12 +80,14 @@ void func7(void) { // CHECK-NEXT: File 0, [[@LINE]]:18 -> [[@LINE+6]]:2 = #0 int kk,ll; // CHECK-NEXT: File 0, [[@LINE+1]]:7 -> [[@LINE+1]]:8 = #0 if (k) // CHECK-NEXT: Branch,File 0, [[@LINE]]:7 -> [[@LINE]]:8 = #1 m(k); // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:9 -> [[@LINE]]:5 = #1 - else // CHECK-NEXT: Expansion,File 0, [[@LINE-1]]:5 -> [[@LINE-1]]:6 = #0 + else // CHECK-NEXT: Expansion,File 0, [[@LINE-1]]:5 -> [[@LINE-1]]:6 = #1 l = m(l); // CHECK-NEXT: Gap,File 0, [[@LINE-2]]:7 -> [[@LINE]]:5 = (#0 - #1) } // CHECK-NEXT: File 0, [[@LINE-1]]:5 -> [[@LINE-1]]:10 = (#0 - #1) // CHECK-NEXT: Expansion,File 0, [[@LINE-2]]:9 -> [[@LINE-2]]:10 = (#0 - #1) - // CHECK-NEXT: File 1, [[@LINE-9]]:14 -> [[@LINE-9]]:18 = #0 - // CHECK-NEXT: File 2, [[@LINE-10]]:14 -> [[@LINE-10]]:15 = (#0 - #1) + // CHECK-NEXT: File 1, [[@LINE-9]]:14 -> [[@LINE-9]]:17 = #1 + // CHECK-NEXT: File 1, [[@LINE-10]]:14 -> [[@LINE-10]]:18 = #0 + // CHECK-NEXT: File 2, [[@LINE-11]]:14 -> [[@LINE-11]]:17 = (#0 - #1) + // CHECK-NEXT: File 2, [[@LINE-12]]:14 -> [[@LINE-12]]:15 = (#0 - #1) int main(int argc, const char *argv[]) { func(); diff --git a/clang/test/CoverageMapping/mcdc-scratch-space.c b/clang/test/CoverageMapping/mcdc-scratch-space.c index 962d10653a028b..2b5b12d9dcad65 100644 --- a/clang/test/CoverageMapping/mcdc-scratch-space.c +++ b/clang/test/CoverageMapping/mcdc-scratch-space.c @@ -1,27 +1,65 @@ -// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c99 -fcoverage-mcdc -fprofile-instrument=clang -fcoverage-mapping -dump-coverage-mapping -emit-llvm-only %s -// XFAIL: * -// REQUIRES: asserts +// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c99 -fcoverage-mcdc -fprofile-instrument=clang -fcoverage-mapping -dump-coverage-mapping -emit-llvm-only %s | FileCheck %s +// CHECK: builtin_macro0: int builtin_macro0(int a) { - return (__LINE__ - && a); + // CHECK: Decision,File 0, [[@LINE+1]]:11 -> [[@LINE+2]]:15 = M:0, C:2 + return (__LINE__ // CHECK: Branch,File 0, [[@LINE]]:11 -> [[@LINE]]:11 = 0, 0 [1,2,0] + && a); // CHECK: Branch,File 0, [[@LINE]]:14 -> [[@LINE]]:15 = #2, (#1 - #2) [2,0,0] } +// CHECK: builtin_macro1: int builtin_macro1(int a) { - return (a - || __LINE__); + // CHECK: Decision,File 0, [[@LINE+1]]:11 -> [[@LINE+2]]:22 = M:0, C:2 + return (a // CHECK: Branch,File 0, [[@LINE]]:11 -> [[@LINE]]:12 = (#0 - #1), #1 [1,0,2] + || __LINE__); // CHECK: Branch,File 0, [[@LINE]]:14 -> [[@LINE]]:14 = 0, 0 [2,0,0] } #define PRE(x) pre_##x +// CHECK: pre0: int pre0(int pre_a, int b_post) { + // CHECK: Decision,File 0, [[@LINE+2]]:11 -> [[@LINE+3]]:20 = M:0, C:2 + // CHECK: Expansion,File 0, [[@LINE+1]]:11 -> [[@LINE+1]]:14 = #0 (Expanded file = 1) return (PRE(a) && b_post); + // CHECK: Branch,File 0, [[@LINE-1]]:14 -> [[@LINE-1]]:20 = #2, (#1 - #2) [2,0,0] + // CHECK: Branch,File 1, [[@LINE-9]]:16 -> [[@LINE-9]]:22 = #1, (#0 - #1) [1,2,0] +} + +#define pre_foo pre_a + +// CHECK: pre1: +int pre1(int pre_a, int b_post) { + // CHECK: Decision,File 0, [[@LINE+3]]:11 -> [[@LINE+4]]:20 = M:0, C:2 + // CHECK: Expansion,File 0, [[@LINE+2]]:11 -> [[@LINE+2]]:14 = #0 (Expanded file = 1) + // CHECK: Branch,File 0, [[@LINE+2]]:14 -> [[@LINE+2]]:20 = #2, (#1 - #2) [2,0,0] + return (PRE(foo) + && b_post); + // CHECK: Expansion,File 1, 17:16 -> 17:20 = #0 (Expanded file = 2) + // CHECK: Branch,File 2, 29:17 -> 29:22 = #1, (#0 - #1) [1,2,0] } #define POST(x) x##_post +// CHECK: post0: int post0(int pre_a, int b_post) { + // CHECK: Decision,File 0, [[@LINE+2]]:11 -> [[@LINE+3]]:18 = M:0, C:2 + // CHECK: Branch,File 0, [[@LINE+1]]:11 -> [[@LINE+1]]:16 = (#0 - #1), #1 [1,0,2] return (pre_a || POST(b)); + // CHECK: Expansion,File 0, [[@LINE-1]]:14 -> [[@LINE-1]]:18 = #1 (Expanded file = 1) + // CHECK: Branch,File 1, [[@LINE-9]]:17 -> [[@LINE-9]]:20 = (#1 - #2), #2 [2,0,0] +} + +#define bar_post b_post + +// CHECK: post1: +int post1(int pre_a, int b_post) { + // CHECK: Decision,File 0, [[@LINE+3]]:11 -> [[@LINE+4]]:18 = M:0, C:2 + // CHECK: Branch,File 0, [[@LINE+2]]:11 -> [[@LINE+2]]:16 = (#0 - #1), #1 [1,0,2] + // CHECK: Expansion,File 0, [[@LINE+2]]:14 -> [[@LINE+2]]:18 = 0 (Expanded file = 1) + return (pre_a + || POST(bar)); + // CHECK: Expansion,File 1, 42:17 -> 42:18 = #1 (Expanded file = 2) + // CHECK: Branch,File 2, 54:18 -> 54:24 = (#1 - #2), #2 [2,0,0] }