X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fadt%2Fgaussjordan.c;h=c07faaa10de8728268d40a0cabf51a8d71050801;hb=e07b61c6ed5d198a484761f8a40a4f26520d964d;hp=f575a584a485e24c6731a3cd102744575a3888e2;hpb=911b30675bfe85e26cc1021d539323334bfd0db1;p=libfirm

diff --git a/ir/adt/gaussjordan.c b/ir/adt/gaussjordan.c
index f575a584a..c07faaa10 100644
--- a/ir/adt/gaussjordan.c
+++ b/ir/adt/gaussjordan.c
@@ -32,7 +32,6 @@
 /* returns 0 if successful                              */
 /* returns -1 if ill-conditioned matrix                 */
 /*------------------------------------------------------*/
-
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
@@ -45,91 +44,96 @@
 
 int firm_gaussjordansolve(double *A, double *vec, int nsize)
 {
-  int i, j, row, col, col2, biggest_r, biggest_c, t;
-  double big, temp, sum;
-  double *scramvec = xmalloc(nsize * sizeof(*scramvec));
-  int *x = xmalloc(nsize * sizeof(*x));
+	int i, j, row, col, col2, biggest_r = 0, biggest_c = 0, t;
+	double big, temp, sum;
+	double *scramvec = XMALLOCN(double, nsize);
+	int    *x        = XMALLOCN(int,    nsize);
+	int res = 0;
 
 #define _A(row,col) A[(row)*nsize + (col)]
-  /* init x[] */
-  for(i=0;i<nsize;i++)
-    x[i] = i;
-
-  /* triangularize A */
-  /* ie A has zeros below it's diagonal */
-  for(col=0;col<nsize-1;col++) {
-    big = 0;
-    /* find the largest left in LRH box */
-    for(row=col;row<nsize;row++) {
-      for(col2=col;col2<nsize;col2++) {
-        temp = fabs(_A(row,col2));
-        if (temp > big) {
-          biggest_r = row;
-          biggest_c = col2;
-          big = temp; /* largest element left */
-        }
-      }
-    }
-    if (big < SMALL) {
-      return (-1);
-    }
-    /* swap rows */
-    for(i=0;i<nsize;i++) {
-      temp = _A(col,i);
-      _A(col,i) = _A(biggest_r,i);
-      _A(biggest_r,i) = temp;
-    }
-    /* swap vec elements */
-    temp = vec[col];
-    vec[col] = vec[biggest_r];
-    vec[biggest_r] = temp;
-
-    /* swap columns */
-    for(i=0;i<nsize;i++) {
-      temp = _A(i,col);
-      _A(i,col) = _A(i,biggest_c);
-      _A(i,biggest_c) = temp;
-    }
-    /* swap unknowns */
-    t = x[col];
-    x[col] = x[biggest_c];
-    x[biggest_c] = t;
-
-    /* partially annihilate this col */
-    /* zero columns below diag */
-    for(row=col+1;row<nsize;row++) {
-
-      /* changes during calc */
-      temp = _A(row,col) / _A(col,col);
-
-      /* annihilates A[][] */
-      for(i=col;i<nsize;i++)
-        _A(row,i) = _A(row,i) - temp * _A(col,i);
-
-      /* same op on vec */
-      vec[row] = vec[row] - temp * vec[col];
-    }
-  }
-  /* back-solve, store solution in scramvec */
-  scramvec[nsize - 1] = vec[nsize - 1] / _A(nsize - 1,nsize - 1);
-
-  /* answer needs sorting */
-  for(i=nsize-2;i>=0;i--) {
-    sum = 0;
-    for(j=i+1;j<nsize;j++)
-      sum = sum + _A(i,j) * scramvec[j];
-    scramvec[i] = (vec[i] - sum) / _A(i,i);
-  }
-  /* reorder unknowns--return in vec */
-  for(i=0;i<nsize;i++) {
-    j = x[i];
-    vec[j] = scramvec[i];
-  }
-
-  free(x);
-  free(scramvec);
-
-  return (0);
+	/* init x[] */
+	for (i = 0; i < nsize; ++i)
+		x[i] = i;
+
+	/* triangularize A */
+	/* ie A has zeros below it's diagonal */
+	for (col = 0; col < nsize - 1; ++col) {
+		big = 0;
+		/* find the largest left in LRH box */
+		for (row = col; row < nsize; ++row) {
+			for (col2 = col; col2 < nsize; ++col2) {
+				temp = fabs(_A(row,col2));
+				if (temp > big) {
+					biggest_r = row;
+					biggest_c = col2;
+					big = temp; /* largest element left */
+				}
+			}
+		}
+		if (big < SMALL) {
+			res = -1;
+			goto end;
+		}
+
+		/* swap rows */
+		for(i=0;i<nsize;i++) {
+			temp = _A(col,i);
+			_A(col,i) = _A(biggest_r,i);
+			_A(biggest_r,i) = temp;
+		}
+		/* swap vec elements */
+		temp = vec[col];
+		vec[col] = vec[biggest_r];
+		vec[biggest_r] = temp;
+
+		/* swap columns */
+		for(i=0;i<nsize;i++) {
+			temp = _A(i,col);
+			_A(i,col) = _A(i,biggest_c);
+			_A(i,biggest_c) = temp;
+		}
+		/* swap unknowns */
+		t = x[col];
+		x[col] = x[biggest_c];
+		x[biggest_c] = t;
+
+		/* partially annihilate this col */
+		/* zero columns below diag */
+		for(row=col+1;row<nsize;row++) {
+
+			/* changes during calc */
+			temp = _A(row,col) / _A(col,col);
+
+			/* annihilates A[][] */
+			for(i=col;i<nsize;i++)
+				_A(row,i) = _A(row,i) - temp * _A(col,i);
+
+			/* same op on vec */
+			vec[row] = vec[row] - temp * vec[col];
+		}
+	}
+
+	/* back-solve, store solution in scramvec */
+	scramvec[nsize - 1] = vec[nsize - 1] / _A(nsize - 1,nsize - 1);
+
+	/* answer needs sorting */
+	for(i=nsize-2;i>=0;i--) {
+		sum = 0;
+		for(j=i+1;j<nsize;j++)
+			sum = sum + _A(i,j) * scramvec[j];
+		scramvec[i] = (vec[i] - sum) / _A(i,i);
+	}
+	/* reorder unknowns--return in vec */
+	for(i=0;i<nsize;i++) {
+		j = x[i];
+		vec[j] = scramvec[i];
+	}
+
+end:
+	free(x);
+	free(scramvec);
+
+	return res;
 }
 
 #undef _A