[llvm] 98f5f02 - [BUG-FIX][XCOFF] fixed a bug of XCOFFObjectFile.cpp when there is padding at the last csect of a sections

[via llvm-commits]

Author: diggerlin
Date: 2019-12-10T11:14:49-05:00
New Revision: 98f5f022f0cb5ac6605385966ced38e1e2851f6b

URL: https://github.com/llvm/llvm-project/commit/98f5f022f0cb5ac6605385966ced38e1e2851f6b
DIFF: https://github.com/llvm/llvm-project/commit/98f5f022f0cb5ac6605385966ced38e1e2851f6b.diff

LOG: [BUG-FIX][XCOFF] fixed a bug of XCOFFObjectFile.cpp when there is padding at the last csect of a sections

SUMMARY:
  Fixed a bug of XCOFFObjectFile.cpp when there is padding at the last csect of a sections.
when there is a tail padding of a section, but the value of CurrentAddressLocation do not be increased by the padding size. it will hit assert assert(CurrentAddressLocation == Section->Address && "We should have no padding between sections.");

Reviewers: daltenty,hubert.reinterpretcast,

Differential Revision: https://reviews.llvm.org/D70859

Added: 
    

Modified: 
    llvm/lib/MC/XCOFFObjectWriter.cpp
    llvm/test/CodeGen/PowerPC/aix-xcoff-mergeable-str.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/MC/XCOFFObjectWriter.cpp b/llvm/lib/MC/XCOFFObjectWriter.cpp
index 3bbf1a9b755a..c7cba91c8612 100644
--- a/llvm/lib/MC/XCOFFObjectWriter.cpp
+++ b/llvm/lib/MC/XCOFFObjectWriter.cpp
@@ -363,7 +363,7 @@ void XCOFFObjectWriter::writeSections(const MCAssembler &Asm,
       continue;
 
     assert(CurrentAddressLocation == Section->Address &&
-           "We should have no padding between sections.");
+           "Sections should be written consecutively.");
     for (const auto *Group : Section->Groups) {
       for (const auto &Csect : *Group) {
         if (uint32_t PaddingSize = Csect.Address - CurrentAddressLocation)
@@ -378,8 +378,10 @@ void XCOFFObjectWriter::writeSections(const MCAssembler &Asm,
     // the current section minus the the end virtual address of the last csect
     // in that section.
     if (uint32_t PaddingSize =
-            Section->Address + Section->Size - CurrentAddressLocation)
+            Section->Address + Section->Size - CurrentAddressLocation) {
       W.OS.write_zeros(PaddingSize);
+      CurrentAddressLocation += PaddingSize;
+    }
   }
 }
 

diff  --git a/llvm/test/CodeGen/PowerPC/aix-xcoff-mergeable-str.ll b/llvm/test/CodeGen/PowerPC/aix-xcoff-mergeable-str.ll
index 1b12ebb7169c..3df01a08f3d5 100644
--- a/llvm/test/CodeGen/PowerPC/aix-xcoff-mergeable-str.ll
+++ b/llvm/test/CodeGen/PowerPC/aix-xcoff-mergeable-str.ll
@@ -8,7 +8,20 @@
 ; RUN: llc -verify-machineinstrs -mcpu=pwr7 \
 ; RUN:     -mtriple powerpc64-ibm-aix-xcoff < %s | FileCheck %s
 
+; RUN: llc -verify-machineinstrs -mcpu=pwr7 -mtriple powerpc-ibm-aix-xcoff -filetype=obj -o %t.o < %s
+; RUN: llvm-objdump -D %t.o | FileCheck --check-prefix=CHECKOBJ %s
+
 @strA = private unnamed_addr constant [14 x i8] c"hello world!\0A\00", align 1
+ at .str = private unnamed_addr constant [9 x i8] c"abcdefgh\00", align 1
+ at p = global i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str, i32 0, i32 0), align 4
+
+; Function Attrs: noinline nounwind optnone
+define i8 @foo() #0 {
+entry:
+  %0 = load i8*, i8** @p, align 4
+  %1 = load i8, i8* %0, align 1
+  ret i8 %1
+}
 
 ; CHECK:      .csect .rodata.str1.1[RO]
 ; CHECK-NEXT: .LstrA:
@@ -26,3 +39,24 @@
 ; CHECK-NEXT: .byte   33
 ; CHECK-NEXT: .byte   10
 ; CHECK-NEXT: .byte   0
+; CHECK-NEXT: .L.str:
+; CHECK-NEXT: .byte   97
+; CHECK-NEXT: .byte   98
+; CHECK-NEXT: .byte   99
+; CHECK-NEXT: .byte   100
+; CHECK-NEXT: .byte   101
+; CHECK-NEXT: .byte   102
+; CHECK-NEXT: .byte   103
+; CHECK-NEXT: .byte   104
+; CHECK-NEXT: .byte   0
+
+; CHECKOBJ: 00000010 .rodata.str1.1:
+; CHECKOBJ-NEXT:       10: 68 65 6c 6c                   xori 5, 3, 27756
+; CHECKOBJ-NEXT:       14: 6f 20 77 6f                   xoris 0, 25, 30575
+; CHECKOBJ-NEXT:       18: 72 6c 64 21                   andi. 12, 19, 25633
+; CHECKOBJ-NEXT:       1c: 0a 00 61 62                   tdlti   0, 24930{{[[:space:]] *}}
+; CHECKOBJ-NEXT: 0000001e .L.str:
+; CHECKOBJ-NEXT:       1e: 61 62 63 64                   ori 2, 11, 25444
+; CHECKOBJ-NEXT:       22: 65 66 67 68                   oris 6, 11, 26472
+; CHECKOBJ-NEXT:       26: 00                            <unknown>
+; CHECKOBJ-NEXT:       27: 00                            <unknown>