diff --git a/src/mesa/program/prog_optimize.c b/src/mesa/program/prog_optimize.c index 0dc779073db..760901af4d9 100644 --- a/src/mesa/program/prog_optimize.c +++ b/src/mesa/program/prog_optimize.c @@ -937,24 +937,35 @@ update_interval(GLint intBegin[], GLint intEnd[], GLuint index, GLuint ic) { int i; + GLuint begin = ic; + GLuint end = ic; /* If the register is used in a loop, extend its lifetime through the end * of the outermost loop that doesn't contain its definition. */ for (i = 0; i < loopStackDepth; i++) { if (intBegin[index] < loopStack[i].Start) { - ic = loopStack[i].End; + end = loopStack[i].End; break; } } + /* Variables that are live at the end of a loop will also be live at the + * beginning, so an instruction inside of a loop should have its live + * interval begin at the start of the outermost loop. + */ + if (loopStackDepth > 0 && ic > loopStack[0].Start && ic < loopStack[0].End) { + begin = loopStack[0].Start; + } + ASSERT(index < REG_ALLOCATE_MAX_PROGRAM_TEMPS); if (intBegin[index] == -1) { ASSERT(intEnd[index] == -1); - intBegin[index] = intEnd[index] = ic; + intBegin[index] = begin; + intEnd[index] = end; } else { - intEnd[index] = ic; + intEnd[index] = end; } }