correct number of iterations

In all these cases the iterations counter is counting up from zero up to the
iteration count, so there is no need to reduce `iterations` by 1.

BUG=none
TEST=add some debug prints show expected number of iterations

Change-Id: Id5dd9025157fb29d2b4924eecb4ec74776bf6a9c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/glbench/+/2775408
Reviewed-by: Ilja H. Friedel <ihf@chromium.org>
Commit-Queue: Ilja H. Friedel <ihf@chromium.org>
Tested-by: Ilja H. Friedel <ihf@chromium.org>
diff --git a/src/bufferuploadsubtest.cc b/src/bufferuploadsubtest.cc
index 3cd3d2e..1000dbd 100644
--- a/src/bufferuploadsubtest.cc
+++ b/src/bufferuploadsubtest.cc
@@ -35,7 +35,7 @@
 
 bool BufferUploadSubTest::TestFunc(uint64_t iterations) {
   GLintptr offset = 0;
-  for (uint64_t i = 0; i < iterations - 1; ++i) {
+  for (uint64_t i = 0; i < iterations; ++i) {
     if (offset + size_ > buffer_size_) {
       offset = 0;
     }
diff --git a/src/bufferuploadtest.cc b/src/bufferuploadtest.cc
index deb2600..8ae1405 100644
--- a/src/bufferuploadtest.cc
+++ b/src/bufferuploadtest.cc
@@ -41,7 +41,7 @@
 };
 
 bool BufferUploadTest::TestFunc(uint64_t iterations) {
-  for (uint64_t i = 0; i < iterations - 1; ++i) {
+  for (uint64_t i = 0; i < iterations; ++i) {
     if (kNumberOfBuffers > 1) {
       glBindBuffer(target_, buffers_[i % kNumberOfBuffers]);
     }
diff --git a/src/cleartest.cc b/src/cleartest.cc
index 30723ff..6e89343 100644
--- a/src/cleartest.cc
+++ b/src/cleartest.cc
@@ -27,7 +27,7 @@
   GLbitfield mask = mask_;
   glClear(mask);
   glFlush();  // Kick GPU as soon as possible
-  for (uint64_t i = 0; i < iterations - 1; ++i) {
+  for (uint64_t i = 0; i < iterations; ++i) {
     glClear(mask);
   }
   return true;
diff --git a/src/readpixeltest.cc b/src/readpixeltest.cc
index 6ef5055..c5d7a63 100644
--- a/src/readpixeltest.cc
+++ b/src/readpixeltest.cc
@@ -28,7 +28,7 @@
 bool ReadPixelTest::TestFunc(uint64_t iterations) {
   glReadPixels(0, 0, g_width, g_height, GL_RGBA, GL_UNSIGNED_BYTE, pixels_);
   CHECK(glGetError() == 0);
-  for (uint64_t i = 0; i < iterations - 1; i++)
+  for (uint64_t i = 0; i < iterations; i++)
     glReadPixels(0, 0, g_width, g_height, GL_RGBA, GL_UNSIGNED_BYTE, pixels_);
   return true;
 }
diff --git a/src/testbase.cc b/src/testbase.cc
index 9b77bf4..71b5a35 100644
--- a/src/testbase.cc
+++ b/src/testbase.cc
@@ -175,7 +175,7 @@
   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
   glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
   glFlush();
-  for (uint64_t i = 0; i < iterations - 1; ++i) {
+  for (uint64_t i = 0; i < iterations; ++i) {
     glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
   }
   return true;
@@ -222,7 +222,7 @@
   glClear(GL_COLOR_BUFFER_BIT);
   glDrawElements(GL_TRIANGLES, count_, GL_UNSIGNED_SHORT, 0);
   glFlush();
-  for (uint64_t i = 0; i < iterations - 1; ++i) {
+  for (uint64_t i = 0; i < iterations; ++i) {
     glDrawElements(GL_TRIANGLES, count_, GL_UNSIGNED_SHORT, 0);
   }
   return true;