COBOL ports - unfinished

COBOL/Makefile

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+# COBOL Parallel Research Kernels Makefile
+#
+# This makefile builds COBOL implementations of PRK benchmarks using GNU COBOL
+#
+
+# GNU COBOL compiler
+COBC := cobc
+
+# Compiler flags for optimization
+COBCFLAGS := -O3 -x
+
+# Default target
+all: nstream transpose p2p dgemm
+
+# Build nstream benchmark
+nstream: nstream.cob
+	$(COBC) $(COBCFLAGS) -o nstream nstream.cob
+
+# Build transpose benchmark  
+transpose: transpose.cob
+	$(COBC) $(COBCFLAGS) -o transpose transpose.cob
+
+# Build p2p benchmark
+p2p: p2p.cob
+	$(COBC) $(COBCFLAGS) -o p2p p2p.cob
+
+# Build dgemm benchmark
+dgemm: dgemm.cob
+	$(COBC) $(COBCFLAGS) -o dgemm dgemm.cob
+
+# Run tests with default parameters
+test: test-nstream test-transpose test-p2p test-dgemm
+
+test-nstream: nstream
+	@echo "Testing nstream..."
+	./nstream 10 100000
+
+test-transpose: transpose
+	@echo "Testing transpose..."
+	./transpose 100 10
+
+test-p2p: p2p
+	@echo "Testing p2p..."
+	./p2p 10 50 50
+
+test-dgemm: dgemm
+	@echo "Testing dgemm..."
+	./dgemm 10 100
+
+# Run benchmarks with larger parameters
+benchmark: benchmark-nstream benchmark-transpose benchmark-p2p benchmark-dgemm
+
+benchmark-nstream: nstream
+	@echo "Benchmarking nstream..."
+	./nstream 10 1000000
+
+benchmark-transpose: transpose
+	@echo "Benchmarking transpose..."
+	./transpose 500 10
+
+benchmark-p2p: p2p
+	@echo "Benchmarking p2p..."
+	./p2p 10 200 200
+
+benchmark-dgemm: dgemm
+	@echo "Benchmarking dgemm..."
+	./dgemm 10 200
+
+# Clean build artifacts
+clean:
+	rm -f nstream transpose p2p dgemm
+
+# Install GNU COBOL (requires package manager)
+install-cobol-ubuntu:
+	@echo "Installing GNU COBOL on Ubuntu..."
+	sudo apt-get update
+	sudo apt-get install -y gnucobol
+
+install-cobol-macos:
+	@echo "Installing GNU COBOL on macOS via Homebrew..."
+	brew install gnu-cobol
+
+install-cobol-fedora:
+	@echo "Installing GNU COBOL on Fedora..."
+	sudo dnf install -y gnucobol
+
+# Check GNU COBOL installation
+check-cobol:
+	@echo "Checking GNU COBOL installation..."
+	@which cobc >/dev/null 2>&1 && echo "GNU COBOL found at: $$(which cobc)" || echo "GNU COBOL not found"
+	@cobc --version 2>/dev/null || echo "GNU COBOL version check failed"
+
+# Help target
+help:
+	@echo "COBOL PRK Makefile"
+	@echo ""
+	@echo "Targets:"
+	@echo "  all              - Build all benchmarks"
+	@echo "  nstream          - Build nstream benchmark"
+	@echo "  transpose        - Build transpose benchmark"
+	@echo "  p2p              - Build p2p benchmark"
+	@echo "  dgemm            - Build dgemm benchmark"
+	@echo "  test             - Run tests with small parameters"
+	@echo "  benchmark        - Run benchmarks with larger parameters"
+	@echo "  clean            - Remove build artifacts"
+	@echo "  install-cobol-*  - Install GNU COBOL (ubuntu/macos/fedora)"
+	@echo "  check-cobol      - Check GNU COBOL installation"
+	@echo "  help             - Show this help message"
+	@echo ""
+	@echo "Requirements:"
+	@echo "  GNU COBOL (cobc) compiler"
+	@echo ""
+	@echo "Usage examples:"
+	@echo "  make all"
+	@echo "  make test"
+	@echo "  ./nstream 10 100000"
+	@echo "  ./transpose 100 10"
+
+.PHONY: all test benchmark clean install-cobol-ubuntu install-cobol-macos install-cobol-fedora check-cobol help test-nstream test-transpose test-p2p test-dgemm benchmark-nstream benchmark-transpose benchmark-p2p benchmark-dgemm

COBOL/README.md

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+# COBOL Parallel Research Kernels
+
+This directory contains COBOL implementations of the Parallel Research Kernels (PRK) benchmarks using GNU COBOL (GnuCOBOL).
+
+## Benchmarks
+
+### Available Benchmarks
+
+1. **nstream** - STREAM triad: `A = B + scalar*C`
+   - Tests memory bandwidth with vector operations
+   - Usage: `./nstream <iterations> <vector_length>`
+
+2. **transpose** - Matrix transpose: `B = A^T`
+   - Tests efficiency of matrix transposition
+   - Usage: `./transpose <matrix_order> <iterations>`
+
+3. **p2p** - Pipeline execution on 2D grid
+   - Tests stencil computation patterns
+   - Usage: `./p2p <iterations> <grid_dim1> <grid_dim2>`
+
+4. **dgemm** - Dense matrix-matrix multiplication: `C += A × B`
+   - Tests floating-point computation performance
+   - Usage: `./dgemm <iterations> <matrix_order>`
+
+## Prerequisites
+
+### GNU COBOL Installation
+
+#### macOS (via Homebrew)
+```bash
+brew install gnu-cobol
+```
+
+#### Ubuntu/Debian
+```bash
+sudo apt-get update
+sudo apt-get install gnucobol
+```
+
+#### Fedora/RHEL/CentOS
+```bash
+sudo dnf install gnucobol
+# or on older systems:
+# sudo yum install gnucobol
+```
+
+#### From Source
+```bash
+# Download from https://sourceforge.net/projects/gnucobol/
+wget https://sourceforge.net/projects/gnucobol/files/gnucobol/3.2/gnucobol-3.2.tar.xz
+tar -xf gnucobol-3.2.tar.xz
+cd gnucobol-3.2
+./configure
+make
+sudo make install
+```
+
+### Verification
+```bash
+cobc --version
+```
+
+## Building and Running
+
+### Build All Benchmarks
+```bash
+make all
+```
+
+### Build Individual Benchmarks
+```bash
+make nstream
+make transpose
+make p2p
+make dgemm
+```
+
+### Run Tests (Small Parameters)
+```bash
+make test
+```
+
+### Run Benchmarks (Larger Parameters)
+```bash
+make benchmark
+```
+
+### Individual Test Examples
+```bash
+# STREAM triad with 10 iterations on vectors of length 100,000
+./nstream 10 100000
+
+# Matrix transpose of 100x100 matrix with 10 iterations
+./transpose 100 10
+
+# Pipeline on 50x50 grid with 10 iterations
+./p2p 10 50 50
+
+# Matrix multiplication of 100x100 matrices with 10 iterations
+./dgemm 10 100
+```
+
+## Implementation Notes
+
+### COBOL Language Features Used
+
+- **Fixed-point arithmetic** with `COMP-3` (packed decimal) for precision
+- **Multi-dimensional arrays** with `OCCURS` clauses
+- **Indexed access** for array operations
+- **Intrinsic functions** for mathematical operations
+- **Command-line argument processing**
+
+### Array Size Limitations
+
+The implementations use statically allocated arrays with these maximum sizes:
+- **nstream**: Up to 1,000,000 elements per vector
+- **transpose**: Up to 1,000×1,000 matrices
+- **p2p**: Up to 500×500 grids
+- **dgemm**: Up to 300×300 matrices
+
+These limits can be increased by modifying the `OCCURS` clauses in the source files, but may require more memory.
+
+### Performance Considerations
+
+1. **Compilation**: Use `-O3` for optimization
+2. **Memory**: COBOL uses significant memory for large arrays
+3. **Precision**: Uses packed decimal for numerical stability
+4. **Timing**: Uses `CURRENT-DATE` function (limited precision)
+
+### COBOL-Specific Adaptations
+
+- **Array indexing**: COBOL uses 1-based indexing (converted from 0-based C)
+- **Variable naming**: Uses COBOL naming conventions with hyphens
+- **Error handling**: Uses COBOL `STOP RUN` for error conditions
+- **I/O**: Uses `DISPLAY` for output formatting
+
+## Troubleshooting
+
+### Common Issues
+
+1. **"cobc: command not found"**
+   - Install GNU COBOL using package manager or from source
+
+2. **Compilation errors about array sizes**
+   - Reduce the problem size or increase array limits in source code
+
+3. **Runtime errors with large arrays**
+   - Check available system memory
+   - Reduce array sizes in the benchmark parameters
+
+4. **Timing precision issues**
+   - COBOL's `CURRENT-DATE` has limited precision for very fast operations
+   - Use larger problem sizes for meaningful timing results
+
+### Platform-Specific Notes
+
+- **macOS**: GNU COBOL works well with Homebrew installation
+- **Linux**: Package manager installations are generally reliable
+- **Windows**: Consider using WSL or Cygwin for GNU COBOL
+
+## Validation
+
+Each benchmark includes validation routines that check:
+- Computational correctness using reference checksums
+- Numerical precision within acceptable tolerances
+- Proper algorithm implementation
+
+Success is indicated by "Solution validates" message.
+
+## Performance Expectations
+
+COBOL performance characteristics:
+- **Strengths**: Excellent decimal arithmetic precision, robust I/O
+- **Limitations**: Generally slower than compiled C/Fortran for numerical computing
+- **Use case**: Demonstrates algorithm implementation in business-oriented language
+
+## Contributing
+
+When modifying the COBOL implementations:
+1. Maintain COBOL coding standards and conventions
+2. Keep array size limits reasonable for typical systems
+3. Preserve numerical accuracy and validation routines
+4. Update documentation for any parameter changes
+
+## References
+
+- [GNU COBOL Documentation](https://gnucobol.sourceforge.io/)
+- [COBOL Language Reference](https://www.ibm.com/docs/en/cobol-zos)
+- [Parallel Research Kernels](https://github.com/ParRes/Kernels)