[mips][micromips] Fix how values in .gcc_except_table are calculated
When a landing pad is calculated in a program that is compiled for micromips
with -fPIC flag, it will point to an even address.
Such an error will cause a segmentation fault, as the instructions in
micromips are aligned on odd addresses. This patch sets the last bit of the
offset where a landing pad is, to 1, which will effectively be an odd
address and point to the instruction exactly.
r344591 fixed this issue for -static compilation.
Patch by Aleksandar Beserminji.
Differential Revision: https://reviews.llvm.org/D57677
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353480 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCExpr.cpp b/lib/MC/MCExpr.cpp
index d8091e4..7ca935f 100644
--- a/lib/MC/MCExpr.cpp
+++ b/lib/MC/MCExpr.cpp
@@ -558,6 +558,11 @@
if (Asm->isThumbFunc(&SA))
Addend |= 1;
+ // If symbol is labeled as micromips, we set low-bit to ensure
+ // correct offset in .gcc_except_table
+ if (Asm->getBackend().isMicroMips(&SA))
+ Addend |= 1;
+
// Clear the symbol expr pointers to indicate we have folded these
// operands.
A = B = nullptr;
diff --git a/test/CodeGen/Mips/micromips-b-range.ll b/test/CodeGen/Mips/micromips-b-range.ll
index 5831ae8..27a0db5 100644
--- a/test/CodeGen/Mips/micromips-b-range.ll
+++ b/test/CodeGen/Mips/micromips-b-range.ll
@@ -13,7 +13,7 @@
; CHECK-NEXT: 1e: fb fd 00 00 sw $ra, 0($sp)
; CHECK-NEXT: 22: 41 a1 00 01 lui $1, 1
; CHECK-NEXT: 26: 40 60 00 02 bal 8 <foo+0x2e>
-; CHECK-NEXT: 2a: 30 21 04 68 addiu $1, $1, 1128
+; CHECK-NEXT: 2a: 30 21 04 69 addiu $1, $1, 1129
; CHECK-NEXT: 2e: 00 3f 09 50 addu $1, $ra, $1
; CHECK-NEXT: 32: ff fd 00 00 lw $ra, 0($sp)
; CHECK-NEXT: 36: 00 01 0f 3c jr $1
@@ -27,7 +27,7 @@
; CHECK-NEXT: 56: fb fd 00 00 sw $ra, 0($sp)
; CHECK-NEXT: 5a: 41 a1 00 01 lui $1, 1
; CHECK-NEXT: 5e: 40 60 00 02 bal 8 <foo+0x66>
-; CHECK-NEXT: 62: 30 21 04 5c addiu $1, $1, 1116
+; CHECK-NEXT: 62: 30 21 04 5d addiu $1, $1, 1117
; CHECK-NEXT: 66: 00 3f 09 50 addu $1, $ra, $1
; CHECK-NEXT: 6a: ff fd 00 00 lw $ra, 0($sp)
; CHECK-NEXT: 6e: 00 01 0f 3c jr $1
@@ -39,7 +39,7 @@
; CHECK-NEXT: 86: fb fd 00 00 sw $ra, 0($sp)
; CHECK-NEXT: 8a: 41 a1 00 01 lui $1, 1
; CHECK-NEXT: 8e: 40 60 00 02 bal 8 <foo+0x96>
-; CHECK-NEXT: 92: 30 21 04 2c addiu $1, $1, 1068
+; CHECK-NEXT: 92: 30 21 04 2d addiu $1, $1, 1069
; CHECK-NEXT: 96: 00 3f 09 50 addu $1, $ra, $1
; CHECK-NEXT: 9a: ff fd 00 00 lw $ra, 0($sp)
; CHECK-NEXT: 9e: 00 01 0f 3c jr $1
@@ -51,7 +51,7 @@
; CHECK-NEXT: 10476: fb fd 00 00 sw $ra, 0($sp)
; CHECK-NEXT: 1047a: 41 a1 00 01 lui $1, 1
; CHECK-NEXT: 1047e: 40 60 00 02 bal 8 <foo+0x10486>
-; CHECK-NEXT: 10482: 30 21 04 00 addiu $1, $1, 1024
+; CHECK-NEXT: 10482: 30 21 04 01 addiu $1, $1, 1025
; CHECK-NEXT: 10486: 00 3f 09 50 addu $1, $ra, $1
; CHECK-NEXT: 1048a: ff fd 00 00 lw $ra, 0($sp)
; CHECK-NEXT: 1048e: 00 01 0f 3c jr $1
diff --git a/test/DebugInfo/Mips/eh_frame.ll b/test/DebugInfo/Mips/eh_frame.ll
index 4687443..122d0a7 100644
--- a/test/DebugInfo/Mips/eh_frame.ll
+++ b/test/DebugInfo/Mips/eh_frame.ll
@@ -1,9 +1,21 @@
-; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -O3 -filetype=obj -o - %s | llvm-readelf -r | FileCheck %s
+; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -relocation-model=static -O3 -filetype=obj -o - %s | \
+; RUN: llvm-readelf -r | FileCheck %s --check-prefix=CHECK-READELF
+; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -relocation-model=pic -O3 -filetype=obj -o - %s | \
+; RUN: llvm-readelf -r | FileCheck %s --check-prefix=CHECK-READELF
+; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -relocation-model=static -O3 -filetype=obj -o - %s | \
+; RUN: llvm-objdump -s -j .gcc_except_table - | FileCheck %s --check-prefix=CHECK-EXCEPT-TABLE-STATIC
+; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -relocation-model=pic -O3 -filetype=obj -o - %s | \
+; RUN: llvm-objdump -s -j .gcc_except_table - | FileCheck %s --check-prefix=CHECK-EXCEPT-TABLE-PIC
-; CHECK: .rel.eh_frame
-; CHECK: DW.ref.__gxx_personality_v0
-; CHECK-NEXT: .text
-; CHECK-NEXT: .gcc_except_table
+; CHECK-READELF: .rel.eh_frame
+; CHECK-READELF: DW.ref.__gxx_personality_v0
+; CHECK-READELF-NEXT: .text
+; CHECK-READELF-NEXT: .gcc_except_table
+
+; CHECK-EXCEPT-TABLE-STATIC: 0000 ff9b1501 0c011500 00150e23 01231e00 ...........#.#..
+; CHECK-EXCEPT-TABLE-STATIC: 0010 00010000 00000000
+; CHECK-EXCEPT-TABLE-PIC: 0000 ff9b1501 0c012d00 002d133f 013f2a00 ......-..-.?.?*.
+; CHECK-EXCEPT-TABLE-PIC: 0010 00010000 00000000 ........
@_ZTIi = external constant i8*
