glslang/fix-encoding-decoding-of-string-literals-for-big-endian-systems.patch

190 lines
5.8 KiB
Diff

From 78ce7e567fce86d611353c5a9194833a54a6fbe0 Mon Sep 17 00:00:00 2001
From: Marius Hillenbrand <mhillen@linux.ibm.com>
Date: Tue, 19 Oct 2021 18:09:52 +0200
Subject: [PATCH] Fix encoding/decoding of string literals for big-endian
systems
Per SPIR-V spec, a string literal's UTF-8 octets are encoded packed into
words with little-endian convention. Explicitly perform that encoding
instead of assuming that the host system is little-endian.
Note that this change requires corresponding fixes in SPIRV-Tools.
Fixes #202
---
SPIRV/SPVRemapper.cpp | 18 +++++++++++------
SPIRV/disassemble.cpp | 47 ++++++++++++++++++++++++++++---------------
SPIRV/spvIR.h | 22 +++++++++-----------
3 files changed, 52 insertions(+), 35 deletions(-)
diff --git a/SPIRV/SPVRemapper.cpp b/SPIRV/SPVRemapper.cpp
index 56d6d5d4a..fdfbeb90c 100644
--- a/SPIRV/SPVRemapper.cpp
+++ b/SPIRV/SPVRemapper.cpp
@@ -297,15 +297,21 @@ namespace spv {
std::string spirvbin_t::literalString(unsigned word) const
{
std::string literal;
+ const spirword_t * pos = spv.data() + word;
literal.reserve(16);
- const char* bytes = reinterpret_cast<const char*>(spv.data() + word);
-
- while (bytes && *bytes)
- literal += *bytes++;
-
- return literal;
+ do {
+ spirword_t word = *pos;
+ for (int i = 0; i < 4; i++) {
+ char c = word & 0xff;
+ if (c == '\0')
+ return literal;
+ literal += c;
+ word >>= 8;
+ }
+ pos++;
+ } while (true);
}
void spirvbin_t::applyMap()
diff --git a/SPIRV/disassemble.cpp b/SPIRV/disassemble.cpp
index 73c988c5b..74dd60540 100644
--- a/SPIRV/disassemble.cpp
+++ b/SPIRV/disassemble.cpp
@@ -43,6 +43,7 @@
#include <stack>
#include <sstream>
#include <cstring>
+#include <utility>
#include "disassemble.h"
#include "doc.h"
@@ -100,6 +101,7 @@ class SpirvStream {
void outputMask(OperandClass operandClass, unsigned mask);
void disassembleImmediates(int numOperands);
void disassembleIds(int numOperands);
+ std::pair<int, std::string> decodeString();
int disassembleString();
void disassembleInstruction(Id resultId, Id typeId, Op opCode, int numOperands);
@@ -290,31 +292,44 @@ void SpirvStream::disassembleIds(int numOperands)
}
}
-// return the number of operands consumed by the string
-int SpirvStream::disassembleString()
+// decode string from words at current position (non-consuming)
+std::pair<int, std::string> SpirvStream::decodeString()
{
- int startWord = word;
-
- out << " \"";
-
- const char* wordString;
+ std::string res;
+ int wordPos = word;
+ char c;
bool done = false;
+
do {
- unsigned int content = stream[word];
- wordString = (const char*)&content;
+ unsigned int content = stream[wordPos];
for (int charCount = 0; charCount < 4; ++charCount) {
- if (*wordString == 0) {
+ c = content & 0xff;
+ content >>= 8;
+ if (c == '\0') {
done = true;
break;
}
- out << *(wordString++);
+ res += c;
}
- ++word;
- } while (! done);
+ ++wordPos;
+ } while(! done);
+
+ return std::make_pair(wordPos - word, res);
+}
+
+// return the number of operands consumed by the string
+int SpirvStream::disassembleString()
+{
+ out << " \"";
+ std::pair<int, std::string> decoderes = decodeString();
+
+ out << decoderes.second;
out << "\"";
- return word - startWord;
+ word += decoderes.first;
+
+ return decoderes.first;
}
void SpirvStream::disassembleInstruction(Id resultId, Id /*typeId*/, Op opCode, int numOperands)
@@ -331,7 +346,7 @@ void SpirvStream::disassembleInstruction(Id resultId, Id /*typeId*/, Op opCode,
nextNestedControl = 0;
}
} else if (opCode == OpExtInstImport) {
- idDescriptor[resultId] = (const char*)(&stream[word]);
+ idDescriptor[resultId] = decodeString().second;
}
else {
if (resultId != 0 && idDescriptor[resultId].size() == 0) {
@@ -428,7 +443,7 @@ void SpirvStream::disassembleInstruction(Id resultId, Id /*typeId*/, Op opCode,
--numOperands;
// Get names for printing "(XXX)" for readability, *after* this id
if (opCode == OpName)
- idDescriptor[stream[word - 1]] = (const char*)(&stream[word]);
+ idDescriptor[stream[word - 1]] = decodeString().second;
break;
case OperandVariableIds:
disassembleIds(numOperands);
diff --git a/SPIRV/spvIR.h b/SPIRV/spvIR.h
index 486e80d00..5249a5ba7 100644
--- a/SPIRV/spvIR.h
+++ b/SPIRV/spvIR.h
@@ -111,27 +111,23 @@ class Instruction {
void addStringOperand(const char* str)
{
- unsigned int word;
- char* wordString = (char*)&word;
- char* wordPtr = wordString;
- int charCount = 0;
+ unsigned int word = 0;
+ unsigned int shiftAmount = 0;
char c;
+
do {
c = *(str++);
- *(wordPtr++) = c;
- ++charCount;
- if (charCount == 4) {
+ word |= ((unsigned int)c) << shiftAmount;
+ shiftAmount += 8;
+ if (shiftAmount == 32) {
addImmediateOperand(word);
- wordPtr = wordString;
- charCount = 0;
+ word = 0;
+ shiftAmount = 0;
}
} while (c != 0);
// deal with partial last word
- if (charCount > 0) {
- // pad with 0s
- for (; charCount < 4; ++charCount)
- *(wordPtr++) = 0;
+ if (shiftAmount > 0) {
addImmediateOperand(word);
}
}